Archive Magazine 1997/ARCHIVE_97.iso/text/magazine/vol_09/issue_02

Text File | 1995-10-03 | 320KB | 6,648 lines

Products Available
9.2
10/10 at half price Ö All the 10 out of 10 products are currently on
offer through Archive for just ú12 each (rrp ú24.95). Subjects
available: Maths (Algebra) (6-16), Maths (Geometry) (6-16), Maths
(Number) (6-16) Maths (Statistics) (6-16), Essential Maths (5-12),
English (6-16), French (8-16), German (8-16), Essential Science (5-12),
Dinosaurs, Driving Test, Early Essentials (3-7), Junior Essentials (5-
11), Spelling (under 9).
9.2
Acorn Education Agency Ö Several schools are asking whether they can
still go on buying computers through NCS, despite Acornæs new Agency
scheme. There are two answers to that, both a qualified yes. First of
all, yes, you can buy computers from us at NCSæs own educational
discount prices. However, our discount prices are about 6% more than the
prices you would pay if you went direct to Acorn. Secondly, if you want
memory upgrades, CD-ROMs, etc, etc added to your computers, you can buy
from Acorn at their educational prices but have them delivered to NCS.
We will then install and test the extra bits and pieces and send the
computers on to you. Even if we have to make a fitting charge and a
carriage charge, it would still work out cheaper than buying the whole
system from us.
9.2
ANT Internet Suite Ö ANT Limited plans to launch its Internet Suite at
the Acorn World 95. The suite provides an easy-to-use integrated set of
programs including a full-featured World Wide Web browser, electronic
mail and Usenet news program, and FTP file transfer. Visitors to ANTæs
stand (80) will be able to buy copies, and there will be some special
offers for Internet users.
9.2
Archive (Internet) Glossary Ö We have created a glossary of Internet
terms which has now reached 12 pages (6,000+ words) long. (This is in
addition to our original glossary of 19 pages and 11,000+ words!) These
two glossaries are available on a disc in Impression, RTF and pure text
form costing ú5 through Archive. If you prefer a paper version, you can
buy a copy of the Archive Glossary Booklet. This is an A5 photocopied
booklet also costing ú5 through Archive. We have deliberately not
printed the booklet because it has to change so rapidly to keep abreast
with new terminology. The disc version is cheaper for us to produce but
is the same price because the price includes a free upgrade service Ö
just send the disc back at any time with a self-addressed adhesive label
and weæll update the disc for you.
9.2
(To increase the effectiveness of the Archive Glossary, please let me
know if there are any missing definitions, or if you disagree with any
of the definitions? Thanks Ed.)
9.2
ARM710 upgrades Ö Now that NCS is an Acorn Centre of Technology, we have
been given permission to sell the ARM710 upgrade(!). The cost through
Archive is ú147, with a credit note for ú30 if you return the old ARM610
processor card (or ú117 if you send the ARM610 with the order). We have
the ARM710 processors in stock, so the turnaround time should be quite
short if you want to save hassle by sending in your ARM610 card with the
order.
9.2
Bible Picture Library CD-ROM Ö Christian Computer Art have released
version 2 of their CD-ROM, containing over 3000 monochrome bit-map
pictures illustrating the Bible, and including all the pictures from the
Good News Bible. The pictures are all scanned at between 300-400 dpi and
are free of any known copyright (except for pictures from the Good News
Bible). A Thumbnail program is included to make viewing easier. Bible
Picture Library costs ú49 +VAT, p&p included. Copies are available on a
30-day trial period.
9.2
CD-ROM drives from Eesox Ö If you want a parallel port CD-ROM drive,
Eesox have improved the speed of their existing Bronze drives (ú205
through Archive) by 35%, to around 290 Kb/s. They have also added a
Bronze Elite drive to their range. This is a quad speed drive giving
over 500Kb/s data rate (<180ms seek time + 256Kb cache) and costs
ú254.47 +VAT from Eesox or ú299 through Archive.
9.2
Parallel port driver Ö Eesox have also developed a parallel port driver
that will allow their Bronze drives to work on PC compatibles. This
costs ú19.99 inc VAT from Eesox.
9.2
Parallel port conversion kits Ö If you have a SCSI CD-ROM drive and also
want to use it via a parallel port, Eesox can provide a special
conversion kit consisting of an adaptor cable and driver software. This
costs ú30 +VAT from Eesox or ú35 through Archive. This conversion kit
works with most SCSI CD-ROM drives. (Eesox also do a PC version at the
same price but this is not available through Archive.)
9.2
N.B. The quad speed Gold ATAPI drives mentioned last month (ú170 through
Archive) only work on the new RiscáPC and A7000, i.e. RISCáOS 3.6 or
later.
9.2
Chris the Bat is a CD-ROM from the Department of Theology and Religious
Studies at the University of Wales. In the story, Chris (the Bat) is
concerned to save his home, an old church condemned to demolition. With
the help of the church mice, they set off to find parts of a treasure
map that they think will save the building. On the journey, they learn
that real treasure is not what they thought and thereby save the church
but lose the building! The program consists of up to 900 full colour
photographs and various interactive games that test pupilsæ
understanding of the material studied. The program explores three
Christian denominations, as well as some of the parables of Jesus Ö itæs
aimed key stage 2/3.
9.2
Version 2 of Chris the Bat and another title, Christian Celebrations
(Key Stage 3), will be available in October from: Rev Michael Morris,
Computers & RE Project, University of Wales, Lampeter, Dyfed, Wales SA48
7ED, price ú55 +VAT.
9.2
Clipart CD Ö The second clipart CD from David Holdenæs APDL is being
made available as we go to press. It is similar in concept to the first
CD, but is all new, with nothing repeated, and has an on-disc viewing
program. The price of the new CD is ú24.50. But, if you have a copy of
the first CD, and are going to the Acorn Show, bring it with you and
Dave will give you a special price for volume 2. Dave also promises to
have at least one PD CD ready for the show, priced at ú19.50.
9.2
Creative Curriculum Software has several new releases. Language Master
builds on the successful concept of ÉSpelling Bookæ which was launched
earlier this year. Language Master does not replace Spelling Book but
provides easy and instant access, from any Acorn Word Processor/DTP
package, to your own lists of words and phrases. User configurable into
any one of four different languages Ö English, French, German and
Spanish Ö this powerful package is suitable for all ages. Language
Master is ú49 (single user), ú89 for a 10-user licence or ú199 for a
site/network. When Report Writer was first released, it was considered
to be a very flexible pupil reporting system. Now, with the new National
Curriculum, Report Writer has been completely redesigned to make it
suitable for reporting on any topic Ö not just for use in Education!
Report Writer (single user) is ú39 (without the new National
Curriculum), ú89 for a 10-user licence or ú199 for a site/network. The
new National Curriculum is ú10 when purchased at the same time as Report
Writer, or úl5 purchased separately. Easimenu is a new Menu System which
allows any Hard Disc RISC OS computer to be set up with a tailor-made
menu. Very easy to use and designed for Primary Schools and on networks
in particular, EasiMenu is only ú14.95 (single user) or ú39 for a site
licence. Magic Maths is a package for learning mental arithmetic and is
designed for Primary School and home use (and for some adults!). Magic
Maths (single user) is ú25.49 or ú89 for a site/network licence. All
prices are ex VAT.
9.2
Fast IDE Interface Ö RapIDE from Yellowstone Educational Solutions is a
32-bit DMA-based interface for the Risc PC. The interface provides
vastly increased throughput. Using alternative drives it is possible to
achieve reading speeds in excess of 8Mb per second with 32-bit direct
memory access. It provides two IDE ports, allowing up to four devices to
be connected, including IDE CD-ROMs. The RapIDE interface costs ú99
+VAT, +ú5 p&p per order.
9.2
Front_end allows users with learning difficulties to load their own
programs easily. Used in place of the desktop, it allows users to type
in their name and be shown only the programs and files they use, without
the need to work their way down a complicated directory structure.
Front_end will also help to prevent accidental messing up of your hard
disc. Requires RISC OS 3 or above. A single users licence costs ú29
+VAT, from NW SEMERC.
9.2
Hard drive price shake-up Ö Two factors are affecting the supply of hard
drives. For fixed hard drives, the coming of memory-hungry Windowsá95
has meant that it is almost impossible to buy a drive less than 500Mb.
The good news is that the 1Gb SCSI drives are now the same price as
340Mb drives were 12 months ago and 4Gb drives are almost as cheap as
1Gb drives were then. The new prices are given in the Price List
Supplement. There is also now a 1Gb IDE internal drive at under ú300 inc
VAT, carriage, fitting kit, and full fitting instructions!
9.2
On the removable drive scene, the much heralded (but not yet quite
available) 135Mb removable drive is affecting the prices of the other
removable drives which have all dropped quite markedly this month. See
the price list for details. The new 135Mb drives when they come
(possibly November) will be completely incompatible with any of the
other drives but have the advantage of being somewhat cheaper. Prices
arenæt fixed yet but it looks as if an external SCSI drive will be about
ú290 inclusive through Archive (cf ú450 for the 270Mb), an internal IDE
will probably be about ú250 (ú370 for 270Mb) and the cartridges about
ú20. If you are just using the removable for backup, the lower price per
Mb of the media is helpful although with hard drives now being 500Mb
minimum, 135Mb is beginning to look a bit small as a backup medium!
Also, if, like me, you want to use them for carrying transient data
around, the speed of the 270Mb drives and the fact that you have more
data on each cartridge will make the 135æs less attractive.
9.2
HTMLEdit is the first commercial, Internet Web Page Authoring System for
Acorn machines. Similar packages have been available for Windows and
Unix for some time, but Acorn owners have been forced to struggle with a
standard text editor. R-Compæs package has been distributed thus far via
the Internet, but the fully packaged version will be available for the
first time at Acorn World. Priced at just ú30 (no VAT) inc p&p, HTMLEdit
represents good value for professional Web Page creation, and is well
within the reach of the home user. ShortCuts, also from R¡Comp, is a
totally new release for the show. This suite of utilities permits
automation of repetitive tasks, such as loading applications, opening
work directories, viewing the contents of discs, and many more. Designed
primarily for ease of use, a flexible short cut editing tool allows the
creation of batch jobs via drag and drop. Several other time-saving
utilities are included, and the whole package retails at ú15 (no VAT)
inc p&p. R-Comp will be on stand 40 at the show.
9.2
InterLink from Liquid Silicon allows the transfer of files and
applications between 32-bit Acorn computers via a serial and or/parallel
link. It is particularly useful for transferring lots of small files or
for transferring large files which will not fit on a floppy disc, e.g.
colour scans, PhotoCD images and Replay files. The parallel cable
versions offer faster rates than serial, though serial cables can run to
over 50 metres in length. A talk option is also included which allows
messages to be passed between the two machines.
9.2
InterLink requires RISC OS 3.10 or later. A300, 400, 500 and the A3000
can only transmit through the parallel port, and so to receive files,
the serial option will have to be used (you can send files via parallel
and receive via serial, hence the option to buy both versions at once).
The prices (inc VAT and p&p) are: Serial 2m ú29.95; 5m ú31.95; 10m
ú35.95. Parallel 2m ú31.95; 5m ú35.95; 10m ú42.95. Serial + parallel 2m
ú43.90; 5m ú49.90; 10m ú60.90.
9.2
Padlock = WatchDog Ö The PadLock application mentioned last month (p7)
has been renamed. This is because an application of the same name
already exists (produced by ICS). Neither Acorn nor Archive knew of the
pre-existing product but, nonetheless, Base5 have changed their product
name to WatchDog, and the Junior version becomes WatchPup!
9.2
Physics Tutor from Kinetic Computing, is a very easy-to-use, but
powerful teaching and revision aid aimed at pupils studying for GCSE
Physics exams. It has a multiple choice format and most questions relate
to a specific statement in the current NEAB syllabus. There are a total
of 270 questions, and students are given the opportunity to re-attempt
all the questions they have answered incorrectly. Also available are
Biology and Chemistry versions in the same vein.
9.2
Physics Tutor will work on all RISC OS computers with a hard disc, 1Mb
of RAM and running RISC 3.0 or later. Site licence: ú120 for each
subject, with all three available for ú250. The individual price on a
stand alone computer is ú25 for each subject or ú49 for all three.
9.2
SENstore is a program designed to help take the burden out of writing
individual education plans for special needs children. It lets you
create a report with up to five different report headings and 15
different topic headings of your choice, simply by clicking the mouse.
It comes with over 750 comments about Strengths, Weaknesses, Targets,
Action Plans, Monitoring, Review and Assessment, across a wide range of
subjects. Itæs easy to alter these or add your own, and you can store up
to 3,750 comments on a hard disc or 1.6Mb floppy disc. SENstore costs
ú34.95 (or ú5 for a working demo version) from NW SEMERC.
9.2
Speak is a software speech system which allows you to listen to text
files. Text may be spoken continuously, or a word or clause at a time.
Various talk-as-you-type options are provided, and simple editing may be
performed while the text is being spoken. The Speak speech system is
already being used within third party educational software, and can be
found in a number of products, including Clicker, Writing with Symbols,
TalkWrite and Talking TextEase. The Speak module and its data takes
about 150Kb, and will run on any Acorn RISC computer. Itácontains a
comprehensive pronunciation dictionary, as well as an exceptions editor.
It costs ú19.50 inclusive, or ú1.50 for a demo version from NW SEMERC.
9.2
Textease 2 and Talking Textease Ö For creative productivity, ease of use
is far more important than functionality and there is no DTP package
easier to use than Textease which has now reached version two. The new
version allows text to be rotated (and still be edited), JPEG support on
RISC OS 3.60, drag and drop editing, Object Linking & Embedding (OLE),
an ellipse tool, arrow heads on lines, customisable button bar. Talking
Textease is the same as Textease with the addition of an extra button on
the button bar to make it start talking Ö highlighting each word as it
is spoken. There is also an option to talk as you type. Textease version
2 costs ú49 +VAT from Softease and Talking Textease is ú65 +VAT or ú55
and ú73 through Archive.
9.2
Touch IT is a touch screen from SEMERC. It is a robust infra-red touch
screen that fixes firmly over the front of 14ö monitors using strong
adhesive anchor pads. The user simply has to touch the computer screen
to play a game etc. This eliminates the complications of using the
keyboard, mouse or switches, allowing users to commit their attention to
the task in hand. The Touch IT comes with a driver disc to allow it to
emulate the mouse. This makes the mouse pointer follow your finger as
you move it around the screen, so you can use the Touch IT with any
software that normally uses the mouse. It fits most 14ò Acorn monitors
(not metal-cased Microvitec ones) Ö you can ring SEMERC if you have
anything unusual. Touch IT costs ú229 +VAT.
9.2
Trellis Adventure Interpreter has been upgraded by Soft Rock Software.
The major change is the addition of graphics. Trellis now displays a
drawfile along with each location in the game, a facility which has been
added thanks to Acornæs drawfile rendering module. The new version is
supplied on two 800Kb discs and, after December 31st, will be priced at
ú8.99 including p&p. Until then, the price will be held to ú7.99.
Existing users of the present version will be sent free upgrades.
9.2
TV splitter cables Ö A complete and inexpensive range of splitter cables
is now available from Eastmond Publishing Ltd (see 8.11 p29). Designed
in association with Acorn Computers, they allow any Acorn computer and
monitor to be connected to a classroom TV. The leads come with stereo
audio link and cost between ú13.50 and ú17.50 (depending on type) +VAT
and p&p.
9.2
Worldæs Weather CD-ROM Ö This CD-ROM from Anglia Multimedia focuses on
the National Curriculum at Key Stage 3, in Geography and Science. The
Worldæs Weather disc offers four principal sections, dealing with
Processes in the Atmosphere, Changing Seasons, Weather and Climate, and
Life in Different Climate Zones. Each section offers the student the
chance to dig more deeply into the subject, with the aid of photographs,
drawings, video and animation sequences. At all stages, text and images
can be extracted from the disc for students to use in their own project
or exam work. The Worldæs Weather costs ú50 +VAT or ú56 through Archive.
9.2
Review software received...
9.2
We have received review copies of the following: ÅBible Picture Library
CD (ae), ÅChris the Bat (e), ÅChristian Celebrations (e), ÅGuardians of
the Greenwood CD (e), ÅSpeak (e), ÅTrellis (u), ÅVistamusic-3 (music
package for the non-keyboard player).
9.2
a=Art, e=Education, b=Business, bk=Book, c=Comms, g=Game, h=Hardware,
l=Language, m=Multimedia, u=Utility.
9.2
If you would like to review any of these products, please contact the
Archive office. Potential reviewers will need to show that they would
use the product in a professional capacity or that they have some
knowledge of the particular field.áuá
9.2
4Mation    14 Castle Park Road, Whiddon Valley, Barnstaple, Devon, EX32
8PA. (01271¡25353) (01271¡22974)
9.2
Acorn Direct   FREEPOST, 13 Dennington Road, Wellingborough, Northants,
NN8á2BR. (01933¡279300)
9.2
Acorn Computers Ltd    Acorn House, Vision Park, Histon, Cambridge, CB4
4AE. (01223¡254254) (01223¡254262)
9.2
Aleph One Ltd   The Old Courthouse, Bottisham, Cambridge, CB5 9BA.
(01223¡811679) (01223¡812713)
9.2
Alsystems   47 Winchester Road, Four Marks, Alton, Hampshire, GU34 5HG.
(01420¡561111)
9.2
Alternative Publishing   Suite 91, 9A Pentagon House, 36 Washington
Street, Glasgow, G3 8AZ. (0141¡248¡2322) (0141¡248¡3638)
9.2
Anglia Multimedia   Anglia House, Norwich, NR1 3JG. (01603¡615151)
(01603¡631032)
9.2
ANT Ltd   P.O.Box 300, Cambridge, CB1 2EG. (01223¡567808) (01223¡567801)
9.2
APDL    39 Knighton Park Road, Sydenham, London, SE26 5RN.
9.2
Avie Electronics (p9)  7 Overbury Road, Norwich. (01603¡416863)
(01603¡788640)
9.2
Base5 Technical Graphics   P.O. Box 378, Woking, Surrey, GU21 4DF.
(01483¡761197)
9.2
Beebug Ltd    117 Hatfield Road, St Albans, Herts, AL1 4JS.
(01727¡840303) (01727¡860263)
9.2
Christian Computer Art   12 Crundale Crescent, Cardiff, CF4 5PY.
(01222¡758484)
9.2
Computer Concepts   Gaddesden Place, Hemel Hempstead, Herts, HP2 6EX.
(01442¡63933) (01442¡231632)
9.2
Creative Curriculum Software   5 Clover Hill Road, Savile Park, Halifax,
HX1 2YG. (01422¡340524) (01422¡346388)
9.2
Cumana Ltd   Pines Trading Estate, Broad Street, Guildford, GU3 3BH.
(01483¡503121) (01483¡503326)
9.2
David Pilling   P.O.Box 22, Thornton Cleveleys, Blackpool, FY5 1LR.
9.2
Eastmond Publishing   33 West Street, Oundle, Peterborough, PE8 4EJ.
(01832¡273444)
9.2
Eesox   Suite 8C, Newton House, 147 St Neots Road, Hardwick, Cambridge,
CB3á7QJ. (01954¡212263) (01954¡212263)
9.2
Icon Technology   9 Jarrom Street, Leicester, LE2 7DH. (0116¡254¡6225)
9.2
IFEL   34 Culver Road, Saltash, Cornwall, PL12 4DR. (01752¡847286)
(01752¡840029)
9.2
Jonathan Duddington   6a Old Mill Avenue, Coventry, CV4 7DY.
(01203¡415535)
9.2
Kinetic Computing   12 Marsett Place, Brookfield, Preston, Lancashire,
PR2 6ST (01772¡795202)
9.2
Liquid Silicon   2 Forth Avenue, Kirkcaldy, Fife, KY2 5PN.
(01592¡592265)
9.2
Longman Logotron   124 Cambridge Science Park, Milton Road, Cambridge
CB4 4ZS. (01223¡425558) (01223¡425349)
9.2
Modus Software   90 Telford Road, Lenziemill Industrial Estate,
Cumberland, Glasgow G67á2NJ.
9.2
Northwest SEMERC   1 Broadbent Road, Watersheddings, Oldham, OL1 4LB.
(0161¡627¡4469)
9.2
Oak Solutions   Dial House, 12 Chapel Street, Halton, Leeds, LS15 7RN
(0113¡232¡6992) (0113¡232¡6993) [e-mail]
9.2
Oregan Developments   36 Grosvenor Avenue, Streetly, Sutton Coldfield,
B74 3PE. (0121¡353¡6044)
9.2
Quantum Software   35 Pinewood Park, Deans, Livingston, EH54 8NN.
(01506¡411162 after 6)
9.2
R-comp   22 Robert Moffat, High Legh, Knutsford, Cheshire, WA16 6PS
(01925¡755043) (01925¡757377) ([e-mail])
9.2
Repair Zone   421 Sprowston Road, Norwich, NR3 4EH. (01603¡400477)
(01603¡417447)
9.2
Sibelius Software   75 Burleigh Street, Cambridge, CB1 1DJ.
(01223¡302765) (01223¡351947)
9.2
Softease   The Old Courthouse, St Peters Churchyard, Derby, DE1 1NN.
(01332¡204911) or (01684¡773173)
9.2
Soft Rock Software   FREEPOST (BS7978), Westbury¡on¡Trim, Bristol, BS10
7BR.
9.2
Texellence   2 Greenhill Road, Coleraine, N Ireland, BT51 3JE.
9.2
Yellowstone Educ.  Solutions   Welbeck House, Welbeck Road, Luton, Beds.
LU2 0HD.
9.2
Archive Monthly Disc
9.2

9.2
u Apollonius sample animation, Dave Wilcox, p77.
9.2
u Beginneræs Basic program, Ray Favre, p43.
9.2
u Beginneræs Edit text, John Temple, p37.
9.2
u C++ article (second half, to be published next month) Tony Houghton,
p38.
9.2
u C++ review (second half, to be published next month) Steve Poulard,
p29.
9.2
u Cassette Inlay printing application, Freeware, Malcolm Knight.
9.2
u Graphics sample, Christopher Jarman (advertising his services).
9.2
u Keystrokes, Stuart Halliday, p6.
9.2
u OPL sample program, Govind Kharbanda, p13.
9.2
u ProArt24 sample, Malcolm Banthorpe, p57.
9.2
u SCSI compatibility chart, Jim Nottingham, p22.
9.2
u Sibelius samples referred to in Ian Beswickæs review on p73.
9.2
u Satellite programs, Francis Crossley, p25.
9.2
Norwich Computer Services     96a Vauxhall Street, Norwich, NR2 2SD.
(01603-766592) (764011)
9.2
áááááááemail: [e-mail]
9.2
Fact-File
9.2
(The numbers in italic are fax numbers)
9.2
Government Health Warning Ö Reading this could seriously effect your
spiritual health
9.2
Only room for a quickie, so Iæll reserve it for a comment from a
Ésatisfied customeræ. Sara came on the first Alpha course we ran at our
local church. öI didnæt realise what Échurchæ was until I came on the
course Ö itæs very different from what I thought Ö not a building but a
group of people who love each other and love God.ò
9.2
Sara also now meets each week with a small group of other Christians to
study the bible, pray for each other and encourage each other. (We need
it Ö itæs not easy being a Christian these days!) She has also been
reading through the bible on her own to try to get an idea of Éthe whole
thingæ. (If you are one of those people who thinks öthe bible is full of
contradictionsò, listen carefully to what someone says who is actually
reading it and studying it, today, 1995.) She made the following
unprompted comment, öYou know, itæs amazing how all the different bits
of the bible hang together Ö they all seem to be saying the same sort of
thing about God.ò When did you last actually read any of the bible? Try
it Ö you might find it different from what you remembered!
9.2
P.B.
9.2
Paul Beverley
9.2
The times they are aæchanginæ
9.2
Itæs hardly what you would call a Édeep, meaningful, incisive commentæ,
but the Acorn community is going through a time of considerable change
at the moment. In fact, the change is so fast, itæs taking me all my
time to concentrate on keeping NCS on the road. Thereæs certainly no
time for quiet contemplation of the significance of all thatæs
happening. That will come later. One thing I would say though is...
9.2
Thanks for all your support!
9.2
Itæs been great to have so many letters and cards pledging support for
Archive and NCS. (Thanks too for the BD cards, faxes and emails!!!) Then
there are the great articles you are sending in Ö perhaps, as editor,
Iáshouldnæt say this but I think the range and depth of articles in
Archive is improving, donæt you? Finally, your orders Ö if NCS and
Archive are to survive the changes, to put it bluntly, we need your
orders.  Theá20/20 scheme (available to the end of æ95) is encouraging
lots of you to think about buying a RiscáPC. We believe that NCS has the
expertise to advise you on the best setup and can provide the after-
sales service you want. And it seems that you agree, because NCS has
been selected (with eight others) as an...
9.2
Acorn Centre of Technology
9.2
The selection was based on feedback from Clan members as to which
dealerships offered the best support. We arenæt quite sure what the
practical implications are yet, but Acorn are pledged to provide the
ACTs with ösupport to help them supply the advanced level of service
looked for by Clan membersò. For our part, we are aiming to improve the
support, the first small step being to open on Saturday mornings. That
might mean that some of you could think of driving to Norwich to collect
your purchases (please ring first to ensure we have what you want).
Saving ú15 on the carriage of a computer could pay for the petrol and
you could have a good day out in Norwich or around Norfolk.
9.2
Come to the Show
9.2
I hope that as many as possible will come and see us at Acorn World 95 Ö
stand 116 Ö you can meet up with other subscribers and contributors,
support the Charity Sale, introduce a friend to Archive (and take issue
with me over something I wrote that you didnæt agree with!?) We want the
Charity Sale to raise lots of money Ö itæs not too late to send stuff to
Norwich but, better still, bring it with you to Wembley. Also, if you
feel you could help out for an hour or so on the Charity Sale, please
let me know. (Sadly, even a stand in aid of charity is vulnerable to
thieving Ö please keep your eyes open, whichever side of the counter
youære on.)
9.2
Time for a change?
9.2
No chance! Thereæs no way Iæm going to leave the Acorn Family!
9.2
Happy reading!
9.2
Keystroke Column
9.2
Stuart Halliday
9.2
From the feedback Iæve had, it seems you all want more on how to
actually use Keystroke generally, rather than how to set up one
application as I did in the last article. So, in this column, Iæll try
to make it more of a hints and tips page.
9.2
One thing I got a lot of questions about was how to upgrade to the
latest version of Keystroke (currently v3.07). If you want the latest
version of Keystroke, return your original Keystroke disc to Quantum
Software and we will upgrade it free of charge, but please enclose two
first class stamps (or two international reply coupons if sending from
abroad).
9.2
Keystroke news
9.2
At the Acorn World æ95 in October, we will be showing off version 4.00
of Keystroke. It has been given a facelift, had some intelligence built
in and, consequently, youæll find that it has been made easier to set up
and use. Also, a totally new and bigger manual has been written by Geoff
Stilwell of The ARM Club fame and the entire manual is in the style of a
tutorial with lots of examples of how things are done. öNot before
time!ò, some people might say.
9.2
These two items should be available from the end of October, but there
will be an upgrade price of ú9.95 in order to get them. I also have to
announce that after the show, Keystroke 4 will be rising slightly in
price to ú34.95 to reflect its increased usefulness. Keystroke has been
the same price since 1992 and we canæt keep it down any longer, I fear.
9.2
Tip of the day
9.2
One of the many useful aspects of Keystroke is to bring up the ÉSave asæ
dialogue box of any application and then perhaps get it to automatically
press <return> Ö a kind of quick save facility. Some users do this by
setting up an ÉInsert textæ command with the text É\F3\|Mæ in the text
box. This is fine and dandy, but what if you want this key press to only
work on a particular application like Paint, but not Draw, for example?
You see, Keystroke has only been programmed to do it for any application
that will respond to the <F3> type keypress.
9.2
Here is how to get it to do it for a specific application. Make the
first Keystroke sequence a ÉMenu selectionæ type. Set this one to your
application by dragging the ÉDrag to setæ icon to the applicationæs
window and leave all the Menu items set to É0æ and only highlight the
ÉWindow at pointeræ and ÉMust match Detailsæ options. Create a second
Keystroke sequence to do the ÉInsert textæ type as before and highlight
the Link option.
9.2
Now, when you start this sequence off, only if the mouse pointer is over
the applicationæs window will the application be forced to perform a
quick save. The Menu selection sequence is not really doing anything in
this case except checking that the pointer is over the application you
want and, since the link option is on, the second sequence is performed
and the file saved.
9.2
New !KeysLib function
9.2
An interesting Keystroke library function has just been donated by Liam
Rudden of Edinburgh. It strips off those irritating É/xyzæ tags off PC
DOS files and then filetypes them as well! Iæve added it to the
Keystroke Library and it works a real treat. I can just point to a
directory, and Keystroke automatically strips off the DOS tags and sets
the correct filetypes of all the files. Thanks Liam for a really useful
function! Weære always on the lookout for useful functions to add to
Keystroke.
9.2
Youæll find a copy of this function and the ones used in the last
article on this monthæs Archive disc. (Yes, Iáforgot to supply the ones
used last month.)
9.2
Finally
9.2
If you have any queries or suggestions for subjects for future Keystroke
columns then please write to me at Quantum Software (with a S.S.A.E.
please) or even send some email!
9.2
Stuart Halliday, 35 Pinwood Park, Livingston, EH54á8NN.
([e-mail])áuá
9.2
Clan Acorn Column
9.2
Simon Ogilvie
9.2
Itæs been a quiet summer as far as the Clan goes, but itæs good to see
that, with Acornæs latest company restructuring, things are starting to
move again. Indeed, the new company structure will hopefully be better
able to design and build products that will be of interest to the
enthusiast market. With ART (Applied Risc Technologies Ö the R+D
division of Acorn) headed up by the highly charismatic Peter Bondar,
enthusiasts are certain of some interesting developments to look out
for. The Clan is still run by Chris Cox who now comes under the Acorn
Education division. This initially appears to be an unusual base for the
Clan until you realise that most Acorn enthusiasts are involved in
education in one way or another, and the educational market is the
largest driving force behind Acornæs development. With Acorn now divided
into smaller and more highly focussed divisions, hopefully the Clan
should be in a better position to build on its original concepts of
dialogue-feeding development.
9.2
Clan Newsletter N║4
9.2
The latest Clan newsletter has recently gone out to members, and
although this is the first one not to include a disc of software, it
includes some very interesting information. Not least of these is the
offer for Clan members who buy a Risc PC or A7000. Instead of the 20/20
finance scheme, Clan members can choose either to receive up to a ú150
rebate or a öProgrammeræs bundleò which consists of the C/C++ package,
the full PRMs and the Style Guide. This package would normally cost
nearly ú400, so represents quite a bargain, especially when you view it
in the light of the ú15 joining fee! Apparently, the offer is even
available for purchases of a machine without a monitor ö...in certain
circumstances...ò, and is valid until the end of the year.
9.2
Also in the newsletter are details of the appointment of Acornæs new MD,
and the restructuring that followed. This includes a öquestion and
answerò sheet that should put many peopleæs worries about Acornæs future
to rest. There has been a lot of discussion on the Internet newsgroups
about the direction of the company under its new MD, and an article in a
recent issue of the Daily Mail left a lot of people with the impression
that Acorn are about to turn into a PC clone manufacturer and that RISC
OS and the Risc PC are to be dropped. This is absolutely not true, and
the Clan newsletter, along with information posted to the newsgroups,
should dispel these rumours. Many people perhaps will be reassured only
by the appearance of new products and new OS releases Ö they will not be
disappointed.
9.2
Acorn Centres of Technology
9.2
A further sign of commitment to enthusiasts is the setting up of Acorn
Centres of Technology. This is in response to requests by Clan members
for ö...facilities, such as showrooms, demonstrating top-of-the-range
systems, customer service phone lines and in-depth knowledge of expanded
systemsò to quote from Acornæs press release. Currently, nine Acorn
dealers have been named under this scheme and will be receiving support
from Acorn to help supply the advanced level of service:
9.2
AJS Computing, Chelmsford, Essex
9.2
Alsystems, Alton, Hants
9.2
Atomwide, Orpington, Kent
9.2
Beebug Ltd, St Albans, Herts
9.2
CJE Micros, Worthing, Sussex
9.2
Davyn, Wakefield, West Yorkshire
9.2
Desktop Projects Ltd, Stockport, Cheshire
9.2
Norwich Computer Services, Norwich, Norfolk
9.2
Uniqueway, Cardiff, South Glamorgan
9.2
This scheme is a direct result of the dialogue between Acorn and the
Clan members, and these nine dealers were all recommended by members
(well done NCS!). Acorn is looking to expand the scheme and welcomes any
further recommendations of dealers who do a good job for enthusiasts.
Suggestions for products or services that they could provide under the
Technology Centre scheme are also welcome. Several of these dealers have
included details of special offers to Clan members in the latest
newsletter.
9.2
(The first spin off from the ACT setup is that NCS can now supply ARM710
upgrades Ö you donæt have to get them via Acorn Direct. Send either ú117
and your old ARM610 chip or ú147 and get a ú30 credit when you return
the ARM610. Ed.)
9.2
Finally, the newsletter has details of the latest generation of Risc PCs
with the new features of Risc OS 3.60, including the new filecore. There
is a form for Clan members to register for the beta test of the filecore
on their own hardware. (This has interesting implications for those who
buy new machines and install different discs in them!) Acorn will not be
releasing 3.60 as an upgrade for existing users, but there will be an
upgrade to a later version which will presumably include changes made as
a result of this beta test. Clan members will therefore have had a
direct input into the development of RISC OS! Unfortunately, I wonæt be
included in this as I have an Oak SCSI card in my Risc PC which does not
appear to support the new filecore, so unless Acorn does a special offer
on SCSI card upgrades, Iæll just have to wait until I can afford a new
machine (again!).
9.2
Acorn World
9.2
This yearæs Acorn World show should have plenty on offer to interest
Clan members. There will be a seminar given by Peter Bondar with entry
restricted to those who show their Clan membership cards, so donæt
forget to take yours with you to the show! As the öhead honchoò of ART,
Peter is in a good position to be able to give an insight into the
future direction of ARM technology as it relates to Acorn computers,
with the development of ARM800 and StrongARM processor cards. Chris Cox
is also giving a talk, on the subject of the Internet, which Acorn are
clearly committed to with their web site, ftp area and email, and
network software is now built-in to the RISC OS 3.60 ROMs.
9.2
Acorn will be showing the multiprocessor card, which is now at a much
more advanced state of development than it was at last yearæs show! In
fact, there is a picture of the card on the Clan page of Acornæs web
site, and you can even download a short Replay movie of it! (I can
confirm it is REAL! Those who went to the Big Ben Club Show in
Hardwijke, Holland saw it in action! Ed.)
9.2
The card plugs into one of the normal CPU slots, and provides two
ömasterò processor slots (one each for an ARM card and a PC card), as
well as five further slots for öslaveò processors. Obviously, the slave
CPUs will not automatically be used by the current version of RISC OS,
but applications could be written to access them in parallel with each
other. Also, TAOS, and perhaps even one of the Unix ports, could use the
multiprocessor capability directly, giving access to a very powerful CPU
resource, even with todayæs technology. With ARM 800 cards, StrongARMs
or later technology, this could lead to some extremely powerful
hardware. This is clearly of little use unless there is the software and
operating system to harness it, but Acorn have already shown that they
are developing this with the multithreaded microkernel (which was on the
first Clan disc), and TAOS. Windows 95 starts to look a very poor
competitor...áuá
9.2
Avie Electronics
9.2
New??? or use 9.1áp9
9.2
Acorn World æ95
9.2
Plans for the event are still very much on course, with Acornæs main
exhibit reflecting their newly announced structure of three operating
divisions: Acorn Education, Applied Risc Technologies (ART) and Online
Media (OM), and with a healthy exhibitor list in evidence.
9.2
This year a myriad of SuperHighway technology will be on show. The
popularity of Technology City, the heart of Acornæs exhibit, is likely
to be matched by that of The Cyber CafΘ area Ö the civilised spot where
anyone can learn about and ÉSurfæ the Internet for free, and by
demonstrations in support of the emerging world of interactive
television.
9.2
For children, thereæs a special attraction Ö Disneyæs Pocahontas. See
clips from the film, meet the characters on Friday and Sunday, win a
Disney GoodyBag, understand how the animation is created through
Disneyæs Film Education, and visit Buena Vista Internationalæs Movie
Plex on the Internet.
9.2
And in the Cyber CafΘ area, computer whizz kids can chat and video-
conference over a special live Internet link with their counterparts on
the Blue Peter stand at the BBC Big Bash in Birmingham Ö which Blue
Peter will be filming at Acorn World on the Friday.
9.2
Special show offers include the A3010 Early Years Computer at ú199 +VAT,
Acorn Pocket Book II, including a free RAM disc for ú205 +VAT, and Acorn
PC Exchange (a new product giving free data exchange between RISC OS and
Windows) for ú25 +VAT. Plus two Pocket Book IIs to be won each day of
the event in a free, twice-daily prize draw Ö just complete a
registration card.
9.2
Not a show to miss! Advance tickets save money Ö information and ticket
hotline [phone].
9.2
Acorn Corporate Affairs.
9.2
Aleph One Limited plans to show new additions to its range of PC cards
running the latest Windows software, including Windows 95, at Acorn
World 95. The companyæs stand (80) will feature the latest models for
the RiscáPC as well as its existing range of expansion cards suitable
for all RISC OS computers, and RiscáPC second processor cards featuring
486 DX-40 and DX/2-80 processors.
9.2
Longman Logotron have two new releases for the Acorn Show. The Big
Picture is an image processing package that takes advantage of the
graphics of the RiscáPC, whilst still being usable on even single Mb
machines. Images, including photographs and video stills, can be
captured, retouched and altered. It incorporates a virtual memory system
which makes it possible to create and edit large images in 32,000 and
16.7 million colours, even with only modest amounts of memory. The Big
Picture supports JPEG, PhotoCD, GIF, TIF, sprites and Clearfiles. It can
also accept drawfiles, which it translates into bit-images. Music Studio
32 is a 32¡track Midi recorder/score writer that offers schools, home
and semi-professional users powerful studio facilities. Music can be
played in and digitised for viewing on the screen prior to editing. Four
editors are available: sequence editor, where music is recorded and
represented as horizontal blocks or bars; a score editor, for editing
within the stave format; a grid editor, for detailed editing where
traditional notation is not required; and layout editor where the score
is tidied up prior to printing.
9.2
MidiWorks Ö Oregan Developments will be showing their forthcoming Midi
sequencer, MidiWorks, at Acorn World 95. MidiWorks answers a demand from
Midi musicians wanting to create music on the RISC OS platform, with a
tool offering professional editing facilities, and playback resolution.
There are no pricing details as yet Ö weæll have more details when they
become available.
9.2
P B Bear Ö Acorn Education has announced the release of ÉP.B. Bearæs
Birthday Partyæ, the first Dorling Kindersley educational CD-ROM title
available for the Acorn RISC OS platform. Other Dorling Kindersley CDs
will soon become available to Acorn users, including ÉThe Way Things
Workæ, due to be shown at Acorn World æ95. Already available in PC
format, the program to enable the discs to run on the Acorn platform was
written by Desktop Laminations. Initially, Acorn users will receive the
PC-format CD and an additional floppy disc containing the data required
for it to run on their RISC OS machine. Together, the package costs ú39
including VAT, available through Kindersley Family Library
distributors.áuá
9.2
Hints and Tips
9.2
Alt(ernative) characters Ö (Thanks to John Woodgate and Jim Nottingham
for stretching my list of special characters in 9.1 p17.)
9.2
I missed out several accented characters out, so here is the full list I
can now create:
9.2
  alt-[  ß ┴ Θ ╔ φ ═ ≤ ╙ · ┌ ² ▌
9.2
  alt-]  α └ Φ ╚ ∞ ╠ ≥ ╥ ∙ ┘
9.2
  alt-;  Σ ─ δ ╦ ∩ ╧ ÷ ╓ ⁿ ▄
9.2
  alt-É  Γ ┬ Ω ╩ ε ╬ ⌠ ╘ √ █ é ü å à
9.2
  alt-,  π ├ ± ╤ ⌡ ╒
9.2
  alt-.  σ ┼
9.2
  alt-/  τ ╟
9.2
To get the accented wæs and yæs for use in Welsh and Spanish, I had to
go back to using Trinity as Plantin does not have them.
9.2
Ed.
9.2
ArcTFS, from Texcellence, was written to run under Arthur on the old
A310 machine, so it will not run from a hard disc. If you happen to have
an old copy, it can be given a new lease of life by a simple brute force
kludge.
9.2
Copy the program to RAM disc and drag it into Edit. Create the following
two extra lines and save the modified program to the RAM disc.
9.2
81 *DISC 0
9.2
82 *MOUNT
9.2
Using Edit, create a simple !Boot file:
9.2
| !Boot file for TFS
9.2
IconSprites <Obey$Dir>.!Sprites
9.2
and a simple !Run file,
9.2
| !Run file for TFS.
9.2
| Alter WimpSlot as required.
9.2
WimpSlot -min 1100K
9.2
IconSprites<Obey$Dir>.!Sprites
9.2
Run <Obey$Dir>.TFS
9.2
Save all three files to the RAM disc.
9.2
Either create a new icon sprite with the name !tfs and save it under the
name !Sprites, or rename an old one and save that.
9.2
On the hard disc, create a new directory called !TFS and drag the four
files to it. Donæt worry if the new icon does not appear; it will, the
next time you switch on. Finally, format a disc using 800Kb (D) option.
9.2
The program can be started by double clicking on the !TFS icon, and the
first thing it will do is to look at drive 0. If it finds your blank
disc or one of your old data files, it will run without any problems.
All the data files must be saved on 800Kb (D) format discs.
9.2
Les May, Rochdale.
9.2
Cleaning HP cartridges (A last ditch measure) Ö Most articles I have
read on the subject of refilling mention that it is not possible to
refill the big HP cartridge because it is manufactured under reduced air
pressure.
9.2
This is not true; all you have to do is find an ink provider who sells
the right equipment (there are at least two in Germany, so there should
be some in the UK, too).
9.2
The trick is simply to blow 5 cm3 of air with a syringe (external
diameter of the needle provided with my refill set is 1.25 mm) through
the hole in the middle of the cartridgeæs cover (in the centre of the
light grey plastic circle) and then plug up the cartridge (I prefer to
use a piece of adhesive tape to cover the hole in the rear right hand
corner which, in a new cartridge, is closed with a little grey plastic
ball pressed into it.)
9.2
After the hole has been covered, both the syringe and the adhesive tape
across the ventilation opening in the bottom of the cartridge can be
removed, and there should be no leakage at all.
9.2
I find it far easier to refill the big cartridges than the smaller ones
which have a sponge inside. Because you can see through them, and
because you simply fill an empty container through a hole, a refill is
completed very quickly Ö I timed the last one I did for a colleague and,
altogether, it took me about 2╜ mins.
9.2
Jochen Konietzko, K÷ln, Germany
9.2
Coloured card Ö I found a source of cheap, coloured card that is fully
inkjet compatible. It is from Staples, called Adagio, weighs in at 160
gsm and is available in about half a dozen colours. 500 sheets cost
ú7.39 inc VAT. Another tip is to ignore Canonæs warning that paper over
100 gsm wonæt work in the BJ200 Ö this card works quite happily, as long
as you remember to set the feed selector to manual (the front position).
9.2
Nigel Caplan, Leeds.
9.2
ÉDeadæ mouse button? Ö If the select button on your mouse wonæt work
with, for example, the Éformatæ button on the floppy disc format window,
first check that you havenæt got Édrag delayæ and Édrag start distanceæ
in the Émouseæ part of !Configure set to zero. It took me a long time to
find that one!
9.2
Stuart Bell, Horsham.
9.2
Hard slash Ö Paul mentioned the splitting of things like É4/5æ across
the end of a line. This seems to be a Publisher Éfeatureæ. One possible
solution is to use the | character (shift-\) for the divider and
italicise it, as: 4|5. This acts as a Éhard slashæ Ö not elegant Ö but
it works Ö except that not all fonts change the vertical line into a
diagonal when italicised. (In Plantin light italic, the | is straight,
as you can see! The one above is a cheat using Trinity. Ed.)
9.2
Jim Nottingham, York.
9.2
Resetting the System beep Ö Lots of programs do horrible things to the
System beep, from changing the tempo to switching it off altogether. One
way to get it back easily is a one line Basic program, affixed to the
Pinboard.
9.2
As my computer stands in a rather noisy room, I load a module öGunshotò
in my Boot sequence to make sure I hear it Ö especially the Alarm Ö even
if I am, at the time, in another part of the room.
9.2
10 OSCLI (öChannelVoice 1 ò+öGunshotò):SYS
öSound_Configureò,0,0,100;SOUND 1,&17F,&4700,1
9.2
The last numbers determine the pitch of the sound Ö you can find the
details in the BBC Basic Guide.
9.2
Instead of öGunshotò, you can use any voice name the computer knows,
including the dull öWaveSynth-Beepò. The built-in voices will need a
different pitch setting though Ö experiment!
9.2
Jochen Konietzko, K÷ln, Germany.
9.2
Risc PC monitors and power saving Ö Have you bought a Risc PC with a
modern monitor (with power saving options), and does the monitor refuse
to switch off if you activate the RISC OS 3.5 screen saver? If so, you
should take a look at your monitoræs definition file which is hidden in
!Boot.Resources.Configure.Monitors.
9.2
One of the first lines in this textfile reads DPMS_state:x, where x (a
number between 0 and 3) defines the behaviour of the monitor.
9.2
0 Ö use just the standard screen blanker
9.2
1 Ö switch the monitor to standby mode
9.2
2 Ö interrupt all signals to the monitor
9.2
3 Ö turn off the monitor completely
9.2
The number you prefer can simply be typed into the file in any text
editor Ö there is no need to use the likes of !MakeModes.
9.2
Of course, if you use one of the many screen-savers on the market, you
can still continue to do so. My personal settings are: Out-to-Lunchæs
fish tank to come on after four minutes, the RISCáOS 3.5 saver (with
DPMS_state:2) after 15 minutes.
9.2
Jochen Konietzko, K÷ln, Germany.
9.2
Snippet and PC486 Ö Snippetæs screen grabbing facility seems to stop
working when the !PC486 software is run. This is, however, only a
question of choosing the right hot keys. <Tab-left-alt>, for instance,
works perfectly even in single tasking mode, as does <capslock-left-
alt>.
9.2
Jochen Konietzko, K÷ln, Germany.
9.2
SyQuests in RiscáPCs Ö A warning to all RiscáPC owners with a 3╜ö
SyQuest in the top right drive position. I have my machine with such a
configuration and a fairly long SCSI lead. An extra connector sits on
top of the SyQuest. It stopped working with what the system said was a
fatal hardware error. I tried to eject the cartridge to find out what
was wrong. The eject lever wouldnæt release to its full extent. The lid
which I had just replaced was pressing the connector of the cable on to
the SyQuest and preventing movement. Rerouting the cable fixed the
problem.
9.2
Chris Walker, Norwich.
9.2
Switching !PC486 to single tasking mode Ö This is one of those bits of
information in the manual that are very easily overlooked. If you want
to change !PC486 to single tasking mode (even if the window is currently
frozen), a double click somewhere on the window is enough Ö there is no
need to go through the iconbar menu. A single click will unfreeze a
window without leaving the multitasking mode.
9.2
Jochen Konietzko, K÷ln, Germany.
9.2
OPL Programming
9.2
Govind Kharbanda
9.2
This new column is intended for readers interested in programming the
Acorn Pocket Book or Psion Series 3 palmtop computers. It is written for
people who are already competent in Basic, and are completely new to OPL
(the programming language for the Pocket Book and Series 3). Rather than
being tutorial in form, it is intended to be more of a programming
forum, with example structures given in BBC Basic with the equivalent
OPL structure alongside. For example, in Basic, you can use FOR ...
NEXT, but in OPL, you canæt! So one of the ₧rst examples I shall give is
to show how that may be achieved in OPL.
9.2
To begin with, I shall guide you through writing a simple OPL program,
to introduce the language. I am using a Pocket Book II, but the
procedure should be similar on other variants. (N.B. OPL is not provided
as standard with the original Pocket Book Ö it has to be purchased
separately Ö ú24 through Archive.)
9.2
Your ₧rst OPL program
9.2
To start off with, weæll turn the following simple Basic program into an
OPL one:
9.2
10 CLS
9.2
20 PRINT öThis is my first Pocket Book programò
9.2
30 a%=INKEY(300)
9.2
40 CLS
9.2
50 PRINT öPress a key to finishò
9.2
60 IF GET
9.2
70 END
9.2
If you want to, you can type it out on your Acorn to see what it does,
if the suspense is too much!
9.2
Go to the Pocket Book system screen (press the Desktop button) and move
to the OPL Program Editor. On the Pocket Book II, you can use the
keyboard short-cut Control-Write to do this. The program editor icon
looks like this:
9.2
Select ÉNew ₧leæ from the ÉFileæ menu (Acorn-N). Create a new ÉProgramæ
₧le with the name of your choice (max. eight letters, e.g. ÉExampleæ). A
blank screen will appear. This is the Program editor.
9.2
You will see that the screen is not entirely blank but PROC : has been
entered on the ₧rst line and ENDP on the third. These two keywords are
used to mark the start and end of a procedure de₧nition Ö the equivalent
of DEF PROC and ENDPROC in Basic. Note that, ináOPL, the space must be
present after PROC and that a colon must be present. Also, procedure
names are limited to 8 characters, like Pocket Book ₧lenames. So, the
equivalent of DEFáPROCdisplayinfo in Basic would be PROCádispinfo: in
OPL. To call the procedure, simply give the name of the procedure (+ the
colon).
9.2
In OPL, there are no line numbers. However, for GOTO freaks, GOTO is
possible in OPL, but I shall come to that later in the series. All OPL
programs, or modules, consist of procedures. Our program, due to its
simplicity, consists of only one procedure. We shall call this
ÉExampleæ. So, alter the top line to read PROC example: and press the
arrow down key to move to the next line.
9.2
You will notice that the cursor is already indented, as if the Tab key
had been pressed. This is not necessary, but it is usual to indent
procedure contents to make them more readable (just like the LISTO
commands in BBC Basic). On the second line, type:
9.2
PRINT öThis is my first Pocket Book programò
9.2
and press <enter>. We do not need to put in the CLS before it because
all programs clear the screen when run.
9.2
The next line makes the computer wait for 3 seconds (= 300
centiseconds). In OPL, there is a simple command, PAUSE, which has the
same effect. PAUSE 20 would wait for one second, so PAUSE 60 would
produce the required effect, i.e. as with the SOUND command in BBC
Basic, durations are measured in twentieths of a second.
9.2
The next line clears the screen. OPL also uses the command CLS, so no
problems there. The PRINT command is also the same.
9.2
IF GET in BBC Basic makes the program wait for the user to press a key.
The equivalent in OPL is just GET. Then, to ₧nish the procedure, we need
the ENDP command which should already be there provided you havenæt
deleted it.
9.2
By now you may be thinking, ÉHow can the people who write these
incredible OPL programs put up with such a small keyboard and screen?æ
Well, you donæt have to! You can write programs using Edit or Zap on the
Archimedes and transfer them via the A¡Link. The only disadvantage is
that you need to transfer the program to the Pocket Book each time you
want to test it. Alternatively, you could use Psionæs Series 3a
emulator, which runs on PCs (including the Risc PC card, I think). I
have not tried this out yet Ö it is freeware, although not supported by
Psion.
9.2
Now your program is ₧nished. Check it through, and then save the listing
using <acorn-S>. (It will be saved as Example, or whatever name you gave
it.) In Basic, we could now run the program. In OPL, we have an extra
stage! It needs to be Étranslatedæ. This creates a separate version of
the program which the Pocket Book can run. To translate, select the
ÉTranslateæ option from the ÉProgæ menu (or use <acorn-T>). Provided the
program is free of errors, it should translate. If not, it will give
some form of error message and you can return to the program, correct
the error, and re-translate.
9.2
Once the program translates successfully, the translated form is saved
and you are given the option of running it. Once you have run the
program, and pressed a key to ₧nish, you are returned to the Program
editor. If you exit to the System screen (press <desktop>), you will
notice a new icon to the right of the Program editor icon. Translated
programs appear under this icon, and can be run by moving onto them and
pressing <enter>. To stop a running program, press <acorn-esc>, or go to
the system screen, move onto the program (which will be highlighted in
Bold), and press <delete>.
9.2
The FOR ... NEXT loop!
9.2
Since there is no FOR ... NEXT loop in OPL, we have to use the
equivalent of Basicæs REPEAT ... UNTIL instead, i.e. DO ... UNTIL.
9.2
The BBC Basic version:
9.2
10 CLS
9.2
20 FOR a%=1 TO 10
9.2
30 PRINT öa% =ò;a%
9.2
40 NEXT
9.2
50 PRINT öFinishedò
9.2
60 IF GET
9.2
70 END
9.2
The OPL version:
9.2
PROC loop:
9.2
ááLOCAL a%
9.2
ááa%=0
9.2
ááDO
9.2
ááááa%=a%+1
9.2
ááááPRINT öa% = ò;a%
9.2
ááUNTIL a%=10
9.2
ááPRINT öFinishedò
9.2
ááGET
9.2
ENDP
9.2
Notice that I always put GET at the end of the program. Unlike Basic,
with its ÉPress SPACE or click mouse to continueæ message, OPL will go
straight back to the system screen at the end of a program.
9.2
Variables
9.2
More about these next month. I shall tell you now, however, that since
you can use upper or lower case letters when entering OPL keywords, you
have to be careful that you donæt use variables with names such as
print%, cursor%, and type$ since PRINT, CURSOR, and TYPE are all OPL
keywords and will be recognised as such. LOCAL must be used to de₧ne any
variables used at the start of a procedure, otherwise you will get an
ÉUnde₧ned externalsæ message when you try translating the program.
9.2
For those of you who canæt wait till next month, I have included some
short programs on the monthly disc, along with their Basic equivalents.
These can either be printed out using Edit and typed into the Pocket
Book, or downloaded using the A-Link. The !ReadMe ₧le has descriptions
of what the programs do, so you can ₧have a go yourself at writing them,
and then compare your version with mine.
9.2
A word of warning
9.2
Donæt make the mistake I didáand order a Pocket Book II Programmeræs
Guide (from Acorn Direct). What you will receive is a Psion Series 3a
Programming Manual (which costs ú5.99 from Psion) and ordering the so-
called Pocket Book II Programmeræs Guide from Acorn cost me ú12.99! Paul
Beverley at NCS con₧rmed that there is in fact no separate Pocket Book
II Programmeræs Guide. But I do suggest you buy the Psion Manual, as it
is very good value, is well written, and has lots of example programs.
It also has a list of all OPL keywords and their usage which is very
helpful.
9.2
Endnote
9.2
I hope the less adventurous Pocket Book users among you will now have
been tempted to try writing something. Donæt despair if your programs
donæt work to start off with Ö feel free to pass them on to me via the
Archive of₧ce and I shall try and ₧x them if I can. I hope to make this
column a regular one but that depends on contributors, so get
programming!áuá
9.2
The Psion 3a Programmeræs Guide is available by sending a cheque for ú6
(made out to Psion UK Ltd) to Customer Services, Psion UK Ltd, 85
Frampton Street, NW8 8NQ or ring them on 0171-262-5580. Ed.
9.2
Operating Systems Column
9.2
Ian Beswick
9.2
Many Acorn users take for granted the most commonly used piece of
software on their machines Ö RISCáOS. This is the operating system,
without which the machine would just be a useless box of electronic
components. RISCáOS provides a very easy to use Graphical User Interface
(GUI). It contains some features not found in other systems, but lacks
certain others...
9.2
As much as we would all like to see the launch of an all-singing-all-
dancing RISCáOS 4, the harsh economic truth is that it simply isnæt
cost-effective for Acorn to develop such a product. Instead, it is more
likely that we will see gradual changes to RISCáOS, coupled with the
ability to run foreign operating systems on Acorn hardware. The first of
these, the Risc PC 486 card, enables the most common operating systems
to be run (i.e. DOS and Microsoft Windows), but this is not the end of
the story.
9.2
In the coming months, we are likely to see an explosion in the number of
operating systems which are going to become available to RiscáPC users.
These developments may come as somewhat of a culture shock to many Acorn
users, particularly the complexities involved in merely installing and
configuring certain systems. This is where this column aims to help,
acting as a forum for information and the exchange of ideas.
9.2
Some of the forthcoming developments which might be covered include the
following (although I suspect that the first three are in the domain of
Mike Clarksonæs RiscDOS Column, so weæll have to compare notes!):
9.2
ÅáHigh performance Risc PC 486 processors (Aleph One)
9.2
ÅáPC hardware compatibility (ISAdaptor)
9.2
ÅáOther PC operating systems on the 486 Card (Windowsá95, OS/2, Unix
etc.)
9.2
ÅáMultiple ARM processors in a Risc PC (Simtec multi-processor card)
9.2
ÅáTAOS micro-kernel operating system
9.2
ÅáUnix running on the ARM processor (RiscBSD)
9.2
ÅáX-Windows (RiscáPC 700X)
9.2
ÅáPowerPC Processor Cards (Aleph1)
9.2
ÅáUtilities for easy sharing of information between operating systems
(AccessPC, OmniClient etc.)
9.2
ÅáAdditions to RISCáOS
9.2
As soon as I can get hold of any firm information (or, better still,
products for review!) I will write about them. In the meantime, if you
have any topics you would like to see covered, advice to offer, comments
or queries on these issues, please write to let me know.
9.2
I am a professional software engineer working mainly on Unix and PC
systems. However, I only intend covering issues concerned with using
operating systems on Acorn computers, rather than clogging Archive with
information better covered in other publications.
9.2
My address is 58 Eden Vale, Worsley, Manchester M28á1YR (Please enclose
an SAE if you would like aáreply).áuá
9.2
Help!!!!
9.2
Beebug HDD problems Ö Advice and/or comments would be appreciated
concerning the continued use of the Acorn-installed 720Kb (Sony)
internal FDD with the Beebug High Density Floppy Disc Controller Board
with an external high density FDD. The internal Sony disc drive light
fails to function. Can this be overcome in any way? Beebug seem unable
to help. Please phone me on 01256-881338 or write to 3, Ringshall
Gardens, Bramley, Tadley, Hants. RG26 5BW. Thanks.
9.2
Michael Rutland, Basingstoke.
9.2
Cassettes for the blind Ö Many thanks to all those who sent in RISCáOS
demo cassettes. It is so encouraging to see just how much goodwill there
is around. If anyone is still wondering about sending cassettes, the
ones that are particularly useful are the double ones that have a
copyright 1991 on them. They are more useful than the 1992 ones because
they are longer, but they are all useful. Thanks. (Bring them along to
the show if you prefer.)
9.2
Ed.
9.2
Cheap colour scanning? Ö Does anyone know of an Acorn Twain driver for
the ColourMobile hand-held colour scanner which connects to the printer
ports of PCs and seems to offer 24-bit colour (105mm wide) at ú149 +VAT,
or ú199 with a feeder? ICS advertise it for use with a PC Card, Windows
and 12Mb(!), but canæt it be used Énativeæ?
9.2
Stuart Bell, Horsham.
9.2
Countdown Ö Does anybody know where I can get a program for öCountdownò?
9.2
Brian Duncalf, Dolgellau, Gwynedd.
9.2
Geoscan on Nexus Ö Now that we have moved over to using a Nexus network,
the Geoscan program has ceased working. It comes up with an öUnable to
move memoryò error. The producers of Geoscan donæt seem to be
contactable anymore. Can anyone help, please?
9.2
Di Hillage, Penzance.
9.2
Internet credit card fraud? Ö Does anyone know if there is any real
danger in sending orders via Internet using a credit card? Someone has
said that there are people around who are scanning messages for four
sets of four digits, and taking them as credit card numbers and using
them. Is there anyone knowledgeable about this? Is there any way of
avoiding it other than, say, sending the numbers in two halves in two
separate emails? Wadja fink?
9.2
Ed.
9.2
Music on the RiscáPC Ö Can anyone tell me what I would need to add to a
RiscáPC in the way of hard/software in order to replace my (BBC
computer) Hybrid Music 5000? Also, does anyone know if any of the people
who composed and programmed Ample music scores moved onto the 32-bit
machines? Did Hybrid ever do anything for the new machines? Can you
sample a Music 5000 through a printer port? Has anyone written anything
to convert Ample format to a RISCáOS package?
9.2
David Barton, Bury St Edmunds.
9.2
Omar Sharifæs Bridge Ö Since losing our main software distributor, we
have not been able to find a supplier for Omar Sharifæs Bridge and so
have had to remove it from our price list. However, we have a reader in
New Zealand who wants a copy so would anyone be prepared to give or sell
us a copy? We will then add a handling charge and send it on to NZ. This
seems the easiest way to do it  because the customer can then pay us,
without any hassle, by Visa (...unless you are prepared to send it
f.o.c. direct to NZ!). Give us a ring if you can help. Thanks.
9.2
Ed.
9.2
ProText Ö Arnor told us some time ago that they were not continuing to
develop ProText for RISCáOS, so I thought Iæd see if I could upgrade to
the PC version. Sadly, my letters have been returned, ÉAddressee gone
awayæ. Does anyone know where they have gone?!
9.2
Charles Martin, Shanklin, IOW.
9.2
High Risc Racing
9.2
Chris Coe
9.2
öIæll review it!ò, I shouted on hearing about a new driving game that
NCS had received for review. When I finally got my grubby mits on it, I
was at first disappointed to discover that this was a birdæs-eye view
game and not a Stunt Racer-type extravaganza. However, these games soon
grow on you...
9.2
The concept is simple. This is a no-nonsense, no ridiculous plot driving
game, the aim being simply to stagger your way around a fistful of
tracks (20 in total, spread over 40 levels) and finish in front of
everyone else. If you finish in 3rd position or better, you get some
money with which you can upgrade your car, or buy one of eight shiny new
models. If you donæt, Iæm afraid itæs game over time, and you have to
start again from level one. Thankfully, you can save your position
between levels!
9.2
The tracks vary from difficult to exceedingly difficult, complete with
the usual oil spillages and pot-holes to avoid. At first, I became very
frustrated with the impossible manoeuvrability of my car... then I read
the instructions! A quick trip to the garage to fit some power-steering,
improved braking and acceleration, plus a handy increase in top speed,
coupled with a little practice at turning corners, and I was soon
zooming around with all the other cars.
9.2
Other things you can purchase at the garage include reduced fuel
consumption, increased fuel tank capacity, tyre and chassis protection,
rocket fuel (for that extra kick in those tricky ten-car pile-up
situations) and two types of missiles for eliminating your opponents:
XorSet missiles move only in a straight line, but the more expensive
Punishers will turn corners and home in on a car Ö very useful! Each
purchase affects things like the caræs trade-in value, the cost of
petrol, new tyres and so on.
9.2
As I said earlier, there are eight cars to choose from; you start with
the pitiful Strata XS at ú95,000 and hopefully graduate to the all-
conquering Hornet Turbo FX, costing a mere ú755,000. As you progress
through the levels, your opponentæs cars improve too, though personally
I couldnæt make money fast enough to keep up with them, which was rather
annoying.
9.2
The title graphics are nothing special, and the in-game graphics really
need some more variety. The actual scrolling is superb, moving in every
possible direction. As for sound, the effects are annoying, as per most
games, but the music fares rather better, with the player being able to
select any of six music tracks. They are by no means brilliant though
and, annoyingly, you have to return to the desktop to change the track
you are listening to. Both effects and music can be switched off.
9.2
Some other items that I would consider important for a driving game are
also missing. There is no practice mode where you are the only car on
the track, and even worse is the absence of a two-player mode, either
split-screen or serial link. In fact, the only driving mode is when you
race round the track with the computer cars, so you are thrown straight
in at the deep end.
9.2
Despite these shortcomings, I enjoyed playing High Risc Racing overall.
It is just let down by the poor in-game graphics and the lack of a two-
player mode. After all, once youæve completed all the tracks once,
youære not going to want to play through them again, so its lifespan has
been somewhat limited. Nevertheless, itæs good while it lasts.
9.2
High Risc Racing costs ú25, and can be obtained from Modus Software.áuá
9.2
Pocket Book Column
9.2
Audrey Laski
9.2
Iæm delighted to report that I have now had so many letters that I must
hold some over for the next column, but I hope that wonæt discourage
anyone with palmtop news, views or problems from writing; this little
flood could easily be followed up by another drought.
9.2
Simultaneity
9.2
David Worden of Colchester, writes that öThe Pocket Book II is quite
brilliantò and reckons that, combined with his mobile phone, it gives
him a miniature mobile office. He finds particularly useful the way
that, having set up a number of applications to run simultaneously, (by
using <shift-enter>), he can switch between them by pressing the
appropriate desktop symbol. Similarly, he uses <tab> to cycle between
different charts in his Abacus spreadsheets, and so can leap about among
three separate diaries, two databases and two spreadsheets each with
multiple charts with the minimum of key presses. Itæsáthis kind of speed
and flexibility which makes the Pocket Book such an extraordinary little
object.
9.2
Lottery fever
9.2
He has used OPL to construct a short program to generate lottery numbers
Ö I have also received an even shorter one from Graham Campbell of
Hathern, Leicestershire. If the lottery has, as I suspect, done far more
harm than good, it has at least given a new impetus to programmers.
Davidæs program uses a number built from the current month, day, hour,
minute and second to seed the RND function, which he reckons gives
17,000,000 different seeds. Grahamæs program is simpler and more direct.
I have no evidence that either of them will make millionaires!
9.2
More about power
9.2
Graham notes that he uses öthe Uniross charger, complete with four
batteries, from Argos. For less than a tenner, thereæs at least 500
charges there.ò He can carry the two spare charged batteries in the ú10
Psion leatherette pouch.
9.2
More about carrying
9.2
ú10 is less than the ú13.95 pouch recommended by Richard Darby in an
earlier column, though his was real leather and so probably better
value. The cheapest way yet noted of attaching the Pocket Book to a belt
is recommended by Mike McNamara of Dunstable, who has found that Tandyæs
general purpose ÉCordless Carry caseæ, though meant for a mobile phone
and therefore a slightly tight squeeze, is öquite suitable for the
Pocket Bookò and costs only ú3.99. Research continues, but it seems
unlikely that this price can be bettered.
9.2
More about the A-Link
9.2
Peter Young of Cheltenham, one of the columnæs regular correspondents,
picks up the observation by Richard Derby in Septemberæs column that
transferring data at 19200 is only recommended for use with post-A5000
machines and claims that his ö(RISC OS 3) A420/1 does not know this, and
has been happily transferring at 19200 for the last nine months.ò
9.2
Screenshot problem
9.2
Peter also writes about the possibility of making Pocket Book screen
shots. He found information about this in the release note (on disc) of
A-link (version 2.03). He says, öIf you press <ctrl-shift-Acorn_S>, this
saves the screen in the Pocket Book root directory as ÉScreen.picæ. This
works perfectly for me, but if I then go on to load this file into
!ChangeFSI (version 0.92), as the release note says, and save the
resulting sprite, I get a pure black sprite, regardless of what the
screen originally showed.ò He hopes that someone with extensive
knowledge about !ChangeFSI can explain how to transfer his sprites
untransformed.
9.2
Clumsy dunceæs corner
9.2
John of the other side of the bed had taken the Pocket Book to the other
side of the bed to make a phone call to a number from our address
cardfile. He was disturbed when the information he was about to draw on
disappeared, plunging him back to the beginning of the address file, and
even more alarmed to find that the whole record had been deleted from
the file. Fortunately, the address book was, backed up on our desktops,
so I didnæt throw him out with nothing but a fine-tooth comb, and we
investigated the disappearance. It turned out that he was clutching the
Pocket Book to his chest and resting the phone on it preparatory to
punching in the numbers. Thus, he pressed down <Acorn> and <space>, and
this combination deleted the current record, without asking for
confirmation. This, I think, is a bug, since it is an effect not
mentioned in the manual; other users beware.
9.2
Endnote
9.2
Pocket Books (or Psions) seem to be playing an important part on the
peripheries of the war in former Yugoslavia. When watching BBC2æs ÉSiege
Doctorsæ, I was delighted to see that one of the British surgeons, who
have taken their skill and courage in their hands and gone to help the
wounded of Sarajevo, was casually using one. Then, in Marcel Ophulsæ
documentary, War Correspondents, one of the international reporters
covering Bosnia waved his palmtop, complaining that he had just
accidentally deleted his report. Another urged him to throw away the
machine and get back to paper technology, but the reply was (more or
less), öNot likely! Iæve got 2000 telephone numbers in here!òáuá
9.2
Me, my Acorn and OSCAR
9.2
James Miller
9.2
Itæs always interesting to know what our customers do with their Acorns.
They are so incredibly versatile, we suspect there are as many answers
as there are users. James recently sent us this report Ö let us have
yours and weæll publish the most interesting ones. Ed.
9.2
Iæve used computers virtually every day for over 30 years, but they only
entered my home in 1984 with the astonishing BBC Micro, which expanded
until it burst. Then, in 1987, came an A420 that also expanded until it
burst. Now I have a Risc PC that looks as if it is more elastic than any
previous machine, but even that may burst in due course.
9.2
These machines have one feature in common and that is that they are on
from breakfast till bedtime, often longer. Iæm a self-employed
electronics engineer, and thereæs virtually nothing that doesnæt get
processed by the Risc PC. Letters, faxes, accounts, record keeping of
all kinds, reports, design, analysis, simulation, drawing, number
crunching, programming, games, Internet email, FTP and WWW; even the CD-
ROM drive is kept busy playing music.
9.2
To my surprise, I find that very little of my software is purchased;
Style, SparkFS and Hard Disc Companion, of course (no-one should be
without those), plus Hearsay, ArcFax, TemplEd and a couple more,
including Flossy the Frog, Jim gets the Sneezes and Grannyæs Garden.
Guess who theyære for?
9.2
The remaining software, some 200Mb at least, is all PD, trawled from
monthly magazine discs, Internet archives or simply written by myself.
Indispensable PD includes StrongEd, Zap and BlackHole (no-one should be
without those either), FYEO2, Creator and Translatr for routine graphics
work and, for Internet use, TCP/IP2, TTFN and ArcWeb. If itæs PD, Iæve
probably got it... somewhere!
9.2
But wait, thereæs more
9.2
While you catch your breath, I have another obsession Ö sorry, Éhobbyæ Ö
amateur radio. This and computers were made for each other as youæll
see.
9.2
Amateur radio is a scientific recreational hobby which attracts 5
million devotees worldwide, including some 50,000 in the UK. The hobbyæs
purpose is self-training and recreation in the art and science of radio
communication.
9.2
Well thatæs the theory, but labels are useless. In practice, there are
as many interpretations of the hobby as there are practitioners, just
like computer users in fact. Amateur radio has scores of interesting
facets; one of the most challenging concerns amateur radio satellites.
9.2
Amateur satellites
9.2
Astonishingly, since 1962 over forty amateur radio satellites have been
built and launched, including the first non-military, non-governmental
and non-commercial satellite. Another in 1965 provided the first
satellite communications of any sort between the USA and USSR.
9.2
Currently, some eighteen of these satellites are operational, and are
being added to at a rate of about two per year. They are used daily by
thousands of radio amateurs. Many satellites include equipment and
facilities that are technically years in advance of commercial practice.
There are, for example, several 9600 bps store-and-forward systems and
bulletin boards which are truly remarkable tours de force.
9.2
My passion for satellites was triggered in 1958 by a childhood trip to
the Sputnik exhibition at Londonæs Science Museum. The seeds of that
visit flowered 25 years later. I began to take an interest in the
technical aspects amateur radio satellites, and before very long Iáwas
devouring their telemetry by the megabyte. That was around 1984 ... re-
read first paragraph.
9.2
Such was my zeal in this endeavour that, quite soon, Iárealised that I
actually knew more about one particular satellite than its controllers
did! That lead to my becoming an ex-officio manager for a few years
until the spacecraftæs demise due to an        electronicáfailure.
9.2
Shortly after, in 1988, AMSAT (Radio Amateur Satellite Organisation)
launched a replacement, its most ambitious satellite up to that date,
OSCAR-13 Ö ÉOrbital Satellite Carrying Amateur Radioæ.
9.2
Thus it was that I found myself a member of the small team that looks
after the day-to-day management of a real live satellite, on behalf of
its thousands of amateur radio users. All the ground command station
hardware and software used to maintain this beast is my own design, and
has evolved over a decade, always using Acorn computers.
9.2
On the buses
9.2
The OSCAR-13 spacecraft is 84kg of spinning metal that carries what are
called Étranspondersæ. These are combined receivers and transmitters. A
user (radio amateur) speaks into a radio from home, beaming at the
satellite. The satellite receives this radio signal, amplifies it and
re-transmits it on another radio frequency back to listeners on Earth.
9.2
The clever bit is that the transponder supports lots of simultaneous
users, and that its orbit takes it over 40,000 km away from Earth. This
means its field of view is practically a hemisphere at a time, thus
linking users on half the planet at once.
9.2
Transponders are merely the payload, the öpassengersò, so to speak. The
structure that carries them is quaintly known as the öbusò. It carries
solar panels and batteries for electrical power, optical sensors to tell
it which way is Éupæ, a system to change its spatial orientation, a
rocket motor, lots of electronics including telemetry gathering and,
most importantly, an on-board computer to coordinate the various
electronic systems.
9.2
Computers in space
9.2
So, from one management point of view, the OSCAR-13 satellite is a
flying computer whose keyboard and screen happen to be on Earth Ö right
in front of me in fact, my Risc PC and, in former years, a BBC Micro and
an A420. Keyboard to spacecraft is the command uplink, and the
spacecraft to screen information flow is the telemetry downlink.
9.2
Commands are created as plain text in StrongEd or Edit, and dragged into
the command window of a program called COM13. This formats the command,
sends it down the serial port to a piece of electronics called the
uplink modulator. This turns serial data into voiceband signals for the
radio to transmit.
9.2
Satellite responses and general telemetry are received by my radio (at
145, 435 or 2400 MHz), decoded into a serial stream and displayed by a
program called TLM13. The data rate is 50 bytes/second which may not
sound much, but itæs there 24 hours/day and is more than adequate. When
the satellite is in a stable situation, the mean information rate is
about 2 byte/sec, and so the satelliteæs health is, in practice,
oversampled.
9.2
It might be of interest to know that the design of the spacecraftæs on-
board computer dates from 1979 and is built around a radiation-hardened
COSMAC 1802 running at only 200,000 instructions/sec. It has 32Kb of
radiation-hardened RAM, and runs a multitasking operating system which
is, on average, 25% loaded, though the peak is 100%. Together with I/O
ports and other services, it consumes well under 1 watt. It has run
since launch in 1988 without crashing, except for a couple of occasions
caused entirely by operator error. I still canæt remember if itæs <data>
<address> POKE or <address> <data> POKE!
9.2
On the iconbar
9.2
Command, Telemetry display and Tracking program are always on the
iconbar, and if my satellite is in view, they will be quietly gobbling
up telemetry for analysis. Through the miracle of RISCáOS multitasking,
and the Internet, it is entirely likely that I might simultaneously be
on-line to collect commands for uplink from one of my colleagues in
Germany and Australia, or indeed to squirt data back to them! Thatæs
thanks to an Intelligent Interfaces dual serial port card.
9.2
Off-Line processing
9.2
In fact, hands-on command and control is only the tip of the management
iceberg. After the spacecraftæs telemetry is gathered, it needs to be
analysed and studied for expected and unexpected happenings. For that
purpose, a large suite of off-line programs is brought to bear. For
example, the spacecraft has highly directional aerials, so itæs
important that theyære kept pointing at the Earth. The on-board optical
sensors are scanning for Sun and Earth, and data from these instruments
is used to calculate the spacecraftæs orientation.
9.2
Not only that, there are factors about the satelliteæs environment that
can be and are pre-computed years in advance, and these generate
constraints within which we have to operate the spacecraft. For example,
when the orbit takes the satellite into the Earthæs shadow it receives
no sunlight, therefore no solar power. So on-board facilities need to be
temporarily shut down. You need to be prepared for this.
9.2
People
9.2
The many users of the satellite need to be told whatæs going on, so an
important job is to create regular news bulletins. These are posted to
the satellite so it can broadcast them via the telemetry stream, to an
Internet mailing list [e-mail], to the worldwide amateur
packet radio network and to various newsletters.
9.2
The manager of a satellite, used by thousands of people worldwide, is in
a socially exposed position, and while few of those users really
appreciate whatæs involved in keeping their hobby alive, a significant
number do. As a result, Iæve acquired a large number of true friends
around the world whose doors are ever open. I know, æcos I pass through
them regularly, and they pass through mine. This social aspect of the
hobby, which you rarely hear about, is quite possibly amateur radioæs
greatest benefit.
9.2
Re-entry
9.2
The computational power of the Risc PC is awesome. A spacecraft is a
lump of metal moving though space subject to various gravitational
forces. Computing its position many years in the future, from its
position and velocity now, can be done by integrating the equations of
motion. An Acorn Risc Computer can do this at a rate of 20 computing
minutes per yearæs flight-time Ö in Basic!
9.2
The satellite is apparently circling the Earth in an orderly manner. But
all is not what it seems. When itæs 40,000 km away from us, the Sun and
Moon exert minute forces (a few micrograms) that have a non-trivial
cumulative consequence. On December 5th 1996 OSCAR-13 will collide with
the upper atmosphere at 7.5km/sec and be transformed into 84kg of
vaporised aluminium as 2.4 Gigajoules of kinetic energy are dissipated
in a flash.
9.2
Then perhaps I can start my re-entry back into the real world? But no;
OSCAR-13æs successor is already under construction. As it is due for
launch at around the same time as the re-entry, I suspect my window of
opportunity is rather narrow!
9.2
RISCáOS rules, OK?
9.2
A less obvious power of Acorn machines is demonstrated by the fact that
two of my colleagues, one in Australia, the other in New Zealand, wedded
to MS-DOS/Windows by myopic employers and the mighty dollar, liked the
flexibility of RISCáOSæs environment so much that, unprompted, they each
bought a 4Mb A3010 with hard disc specifically for OSCAR-13 satellite
management. Theyære now finding itæs pretty good at other jobs too!
9.2
Contacts
9.2
Amateur radio satellites cost a fortune to build and maintain. AMSAT
exists in groups worldwide to coordinate the effort. For further
information, send a large SAE to Amsat-UK, London, E12 5EQ. Also see
http://www.amsat.org/amsat/
9.2
My email address is: [e-mail]áuá
9.2
At Kourou, French Guiana June 1988. The completed amateuráradio
satellite OSCAR-13 awaits assembly ontoáanáAriane rocket just prior to
launch.
9.2
Some OSCAR-13 satellite telemetry information. Fresh data arrives every
30 seconds. There are logging and replay facilities. This program is
available from Amsat-UK.
9.2
The command window; about to transmit a user bulletin to the amateur
radio satellite OSCAR-13.
9.2
More on SCSI Compatibility
9.2
Jim Nottingham
9.2
A little while ago, I was asked if and when there would be another
update of the SCSI card compatibility survey which originally appeared
in Archive in November 1994 (Issue 8.2). My answer was öYes, probably in
1996ò. So here it is...
9.2
Actually, updating has been an ongoing activity as fresh data and news
have dribbled in and readers have been asking for information and ideas.
The first published update appeared in Archive 8.5 (February) and with
some recent, significant moves on SCSI interface availability, itæs as
good a time as any for this second revision.
9.2
It will be presented in the same format and use the same terminology as
before Ö you may need to refer back to the two earlier issues to refresh
your memories. New subscriber? Donæt worry, Iæll send you copies of
those reports on request Ö details below.
9.2
The database
9.2
I think it fair to say the value of the survey is improving all the
time. Not only are there additional interfaces and devices listed but
many more reports are being received which indicate those areas where
difficulties are few and far between and, just as importantly, where
difficulties lie. I donæt mind in the least getting duplicated
information Ö that just improves the general level of confidence.
Numerically, there are now many hundreds of data points Ö around six
times more than were available for the original survey.
9.2
The big problem (literally) is that the present table wonæt fit into
Archive! Not unless we talk Ed. into changing to an A4 format and grab a
double-page spread. So instead, the table is included on the monthly
disc as a drawfile, sized to fill an A3 page. To be able to read the
various symbols, you will first need to load Acornæs Selwyn font into
your !Fonts folder (or equivalent), before loading Draw. Selwyn comes
with your computer (RISC OS 3 or later) but, if you canæt find the
support disc, you will also find it on the monthly disc. (If there is
space! Ed.)
9.2
The code is the same as before. Every tick represents a reader-report of
a satisfactory Éplug in and goæ combination of that SCSI device and
interface; a cross represents a reported incompatibility; a ÉPæ is a
scanner report from David Pilling ( with his Twain drivers); an ÉAæ is a
report from Alsystems (regarding the NEC CD-ROM drives they supply).
9.2
An asterisk indicates either where success was achieved only after one
or more problems had first been ironed out or, alternatively, where
there is a residual adverse operating feature or limitation. The few
question marks cover areas where reports conflict; one reader recording
a failure but another enjoying success with the listed device and
interface.
9.2
The drawfile could be reduced to A4 for printing but, frankly, I doubt
whether it would be readable at much less than 600dpi, if then. If you
want a copy of the drawfile on disc and/or an A3 printout, please do ask
me. Again, details are given below.
9.2
The SCSI interfaces
9.2
In a number of cases, later versions of SCSIFS and CDFS in interface
firmware have been reported, so the relevant data has been updated as
shown.
9.2
Two VTI cards have been added to the range of SCSI interfaces; a
standard-size 16-bit podule and an 8-bit variant for A3000 etc, both
with user port and the latest versions of firmware.
9.2
A few interfaces are known to be no longer in production but Iæve
purposely left them on the table as they are still in use and it may
help owners who are considering adding further devices to their systems.
In any event, some obsolete cards are still supplied and/or supported by
other manufacturers.
9.2
For example, the ex-Lindis/Lingenuity interfaces are available from
Castle Technology (along with their own range of cards) and software/
firmware upgrades are available for existing owners. Supplies of the
popular Oak card are now available from IFEL, as are CDFS upgrades for
older cards. Details and prices were given in Archive 9.1 p7 but IFELæs
address was omitted so is included with this issue.
9.2
SCSI 2
9.2
The Cumana SCSI 2 interface is now well-established. All the asterisks
under this interface relate to the need to obtain or update software
support modules (e.g. drivers) in the early days. With the exception of
one reader who is having difficulties with his two SyQuests and Fujitsu
hard drive (under investigation), no problems have been reported lately.
9.2
A recently-introduced alternative to the Cumana card is the Alsystems
Power-tec interface; outline details and prices were given in Archive
9.1 p3 and I can supply some additional brochure detail on request.
Castle Technology have a 16-bit card available which they say is SCSI 2-
compatible but, at the time of writing, I havenæt any further details on
that, so watch for it in Products Available in due course.
9.2
It may be worth stressing that, to achieve full SCSI 2 performance, not
only must the interface be fitted to one of the bottom two slots in the
Risc PC (i.e. slots 0áor 1) but, in addition, the device(s) may also
have to be set to SCSI 2 (this may need a DIP switch setting or a link
to be changed). Some older devices simply may not be capable of SCSI 2
performance. Aágeneral problem here seems to be the very poor standard
of supporting documentation for SCSI devices, so you may need to chase
up the supplier or manufacturer on this point.
9.2
Hard disc drives
9.2
A few more drives have been added to the table with no major
compatibility problems reported.
9.2
Two new Éfeaturesæ have surfaced however. A number of readers have
mentioned that certain drives are rather noisy and, installed in a Risc
PC, can be quite intrusive. I have personal experience of this, having
moved a Fujitsu 540Mb drive into a Risc PC from a back-up A540 Ö only to
quickly return it to the Éwind tunnelæ from whence it came! Others have
also commented on how noisy the Fujitsu drives are, especially when
winding up and down, so they no longer use the power-save feature.
Quantum drives had a couple of öa bit noisyò reports but, from a
personal viewpoint, Conner drives seem to be unobtrusive.
9.2
The other one is the formatting Éfunnyæ discussed in Archive 9.1 p42.
This is the one where, if you set up a PC partition to use up all the
available space on the drive, the partition size can be apparently
larger than the free space available. To give a specific example, my
nominally 170Mb Quantum drive will return only 163Mb once formatted Ö
but will happily take a 170Mb PC partition. This phenomenon seems to
apply to all storage media, whether SCSI or IDE, fixed or removable
(e.g. SyQuest).
9.2
Cartridge drives
9.2
The SyQuest drives are becoming a very common and popular device in
reader-reports. The sheer convenience, speed and reliability of the
higher-capacity drives (e.g. 270Mb) is a frequent comment, while the
reducing cost of additional cartridges is making these drives an
increasingly economic option, even in the face of falling hard disc
drive prices.
9.2
Virtually all the asterisks under the Morley interfaces refer to the
problem reported in the earlier issues whereby, if a cartridge is not
inserted at start-up or shutdown, the computer may hang up or crash. I
am awaiting further advice from Morley on this one.
9.2
If anyone is considering getting a SyQuest drive for a Risc PC and isnæt
sure whether to opt for an IDE or SCSI version, I would advocate the
latter. My own IDE drive works a treat, but changing cartridges is not
so convenient as the SCSI version, as it requires the use of a rather
unwieldy icon-bar module for dismounting/mounting, to force the drive to
recognise the new cartridge (not required for SCSI drives). (Iáuse one
of each, and the IDE version drives me crazy!áEd.)
9.2
Magneto-optical (MO) drives
9.2
Iæve had no more reader-reports on MO drives since the last publication
but Cumana have come in with the Proteus, an interesting single-box,
multi-function solution which combines a conventional, quad-speed CD-ROM
drive with a 650Mb read-write MO drive.
9.2
CD-ROM drives
9.2
Although the range of CD-ROM drives available for use with Acorn
machines is becoming extensive, many of these are packaged IDE or
parallel port devices, so the SCSI range in this report isnæt much
larger than in the previous review. However, many more reader-reports
have been received indicating few problems which we donæt already know
about.
9.2
Soon after the last update, the reported anomaly with the Morley
Revolution Pro driver for Toshiba drives was resolved, so anyone still
having problems should contact Morley for an update (mine is v1.10 and
works fine on the Toshiba XM-3401).
9.2
Scanners
9.2
Falling scanner prices and a widening range of available models in the
last year or so have resulted in a big increase in the user-base. David
Pilling has again very kindly provided a wealth of advice based on his
testing in relation to his Twain drivers (öPò in the table) and which,
on the face of it, indicates the Ésafe areasæ.
9.2
The question marks in the table highlight the combinations where reports
of both success and failure have been received. David suggests this
might be due to firmware variations in later versions of some scanners
and/or alleged hardware variations in Oak interfaces. In two cases,
readers were able to resolve problems by getting firmware updates for
their SCSI cards.
9.2
Help wanted...
9.2
The value of these SCSI compatibility surveys can be only as good as the
data received, whether it be from manufacturers (not always readily
forthcoming), people like David Pilling (always very helpful) or
readersæ experiences. In this, a goodly proportion of recent data has
come from my spotting references to readersæ SCSI systems in Archive and
following them up with an invitation to the people concerned to
contribute to the database.
9.2
This bears out what I said in the original report that there are
probably far more readers out there with SCSI kit who have yet to add to
the database. So I hope Ed. wonæt mind if I simply repeat my earlier
requests that, if any reader is running a SCSI system but hasnæt yet
given me details (hint: I spotted two in Archive 9.1...), please could I
invite you to let me have full information. To be of maximum benefit, we
need to know the following:
9.2
Ö Computer model number, e.g. A410/1.
9.2
Ö Make + model of SCSI card, e.g. Morley cached.
9.2
Ö Version number of the SCSI software installed, e.g. v1.12. (How to get
this varies between interfaces, so probably the easiest way to do it is
to press <f12>, type *Help SCSIFS <return> and read off the number
returned after öModule is: SCSIFS...ò).
9.2
Ö Make, model number and other details of your SCSI devices. (Again, how
to do this varies between interfaces. Many will respond to pressing
<f12> and typing *Devices <return> but others do it by running !SCSIForm
or similar and doing a [S]can. In theory, the user-manual should tell
you the procedure.)
9.2
Ö Name and version of software drivers for the device(s), where
applicable. For example, to read the version of CDFS, press <f12> and
type *Help CDFS <return>. The answer will look something like öModule
is: CDFS v2.21ò.
9.2
Ö Whether the device works or does not work correctly with the SCSI
card. If not, how does the problem show up? Did you manage to solve the
problems and, if so, what was the solution?
9.2
Ö Ease or difficulty of connecting up, e.g. are the connectors standard?
9.2
Ö Any comments on manufacturer/dealer support?
9.2
Please do respond, even if your combination(s) of interface and
device(s) are already covered in the survey. The more the merrier and
two reports are better than one.
9.2
Help offered
9.2
So what do you get in return? If anyone would like a copy of the table
as a drawfile, please send me a formatted disc and return postage (I
damaged my disc drive last month so, sorry folks, from now on Iæll have
to insist on the use of a Jiffy-style bag; please see Archive 8.10 p14.)
9.2
If you would like an A3 printout of the table, or if recent subscribers
who donæt have access to the earlier issues would like a copy of the
text, or if you are considering a particular combination of interface-
device which has an asterisk against it and would like a copy of the
reader-report(s), let me know and include return postage; Iæll provide a
suitably-sized envelope. (If you want the lot, it might be safer to send
2á╫á19p stamps; Iæll return any surplus).
9.2
Finally, if you are having problems either with your system or getting
adequate support from the supplier, please donæt hesitate to send me
details. Iæm not a techie but will be happy to search through the
reports for clues or ideas and let you have them. We know that, to date,
and directly as a result of this survey, at least ten readers have
managed to either solve their problems or, failing that, get a usable
workaround. Also, we know of others who have avoided reported problem
areas and are happy with alternative choices. The information is there
so donæt hesitate to ask. Myáaddress is 16 Westfield Close, Pocklington,
York,áYO4 2EY.áuá
9.2
Receiving Weather Charts
9.2
Francis Crossley
9.2
This article explains how I am using C and assembler to receive and
display weather charts, broadcast by meteorological stations on short
wave. Many interesting maps can be received Ö only a few months ago, I
obtained a map showing the limits of ice around the N. Atlantic and
Northern Europe.
9.2
The system consists of several parts Ö a short wave radio, some
electronics to convert audio tones, provided by the receiver, into
digital signals for the computer and the software required to convert
the digital signals into a picture. This article outlines the production
and format of the facsimile signal, and the basic functions of the
electronics part but concentrates on the software I am using to provide
the picture. My system does not yet perform exactly how I want it to but
the ideas presented here might be useful, if only to provoke a
discussion!
9.2
The weather chart signals
9.2
A weather chart is drawn on a sheet of paper about 480╫660 mm. It is
scanned in some way to produce a continuously varying voltage which is
used to modulate the transmitter. In the original systems the chart was
wrapped on a large drum, about 152mm in diameter and 660mm long. The
drum rotates at a fixed known speed, usually 2 revolutions each second.
9.2
A lamp and photodetector unit moves along the drum so that a fine pitch
spiral is traced out on the chart. Over the course of 10 to 15 minutes
the whole chart is scanned. The output of the detector is a voltage
which represents the brightness of the drawing on the chart as it is
scanned point by point.
9.2
This voltage is used to change the frequency of the transmitter by a
very small amount; usually 400Hz too high represents white and 400Hz too
low corresponds to black. Half tone charts can be transmitted, in which
case, intermediate changes in frequency represent shades of grey. On the
radio, the signal is said to sound like a squeaky wheelbarrow!
9.2
Retrieving the chart
9.2
A short wave radio can receive the weather chart transmissions and, with
suitable hardware and software, a computer is used to display the chart.
Much software is available for PC-type machines, but it would not be
Éplaying the gameæ to buy one of these, so I built my own hardware and
wrote my own programs. The hardware consists of a special filter which
converts the changes in frequency into a varying voltage which is
sampled at the correct times by an analog to digital converter (A/D).
The digital output is sent to the computer using a versatile interface
adapter (VIA) and an Apec prototype board, which I described in Archive
6.2 p25. The computer then writes the digital value to screen memory.
Simple? In principle, yes, but in practice rather more must be done.
9.2
Hardware and software functions
9.2
There are three major functions that the system must perform. (1) It
must sample the incoming data regularly at the correct frequency. (2) It
must be able to start a new line on the screen at the correct time. (3)
As the chart takes 10 to 15 minutes to complete, itáis very convenient
to leave the equipment switched on and let the system detect the start
and end of eacháchart.
9.2
Some of these functions can be aided by hardware. For example, the
sampling is done using a fast A/D which is told when to sample (convert)
by pulses produced by the VIA Ö software then reads the digital value
when it is ready. The start and end of the charts are signalled by
particular tones which can be detected by hardware, thus informing the
program when to start or stop displaying the chart.
9.2
So far, my system displays a chart on the screen, but cannot orientate
the chart perfectly. I suspect that, unless the starting point of each
line is found, the sampling frequency must be correct to better than
1ápart in several thousand. My reasoning is that, with 640 pixels per
line on the screen, an error of 1 part iná640 would start the next line
one pixel wrong. Theánext line would start with another pixel in error,
thus producing a sloping line. Only with errors muchásmaller than this
would a good vertical line beáachieved.
9.2
The software
9.2
Now that we know, in broad terms, what the system must do, how have I
implemented it? The software is in two programs, one written in C and
the other in assembler (using the Wingpass Macro Assembler v 2.00). I
like using assembler but I use C for the harder parts. For example, one
version of the program uses data saved on the hard disc Ö opening a file
using C is easy, so I have not bothered to learn how to do it using
assembler. The C program contains a number of definitions of VIA address
offsets which make understanding the program easier, since a few well
chosen letters replace numbers. The complete program is on the monthly
disc, so I will not go through all of them here. Also, before the main
program, are several subroutines which again make writing and
understanding the program easier. These subroutines are to write and
read the VIA and hence, in the outside world, they are used as:
9.2
y=aread(offset) ;
9.2
and
9.2
awrite(offset,y) ;
9.2
where offset is an address in VIA space lying between 0 and 15; y is the
value being read or to be written. Since C does not know anything about
the Apec board etc, Acorn has supplied a number of very useful general
purpose commands in a file called Ékernel.hæ. The one I use most is:
9.2
_kernel_swi(code,ptr1,ptr2) ;
9.2
It is a command to call any software interrupt (swi) and is used as
follows. Four variables are declared as:
9.2
_kernel_swi_regs point1, point2, *ptr1, *ptr2 ;
9.2
Époint1æ and Époint2æ are variables of type É_kernel_swi _regsæ, and
Éptr1æ and Éptr2æ are pointers to this type of variable. Éptr1æ must be
made to point to Époint1æ using:
9.2
ptr1=&point1 ;
9.2
ptr2=&point2 ;
9.2
Époint1æ is actually a variable which allows us to place values into any
of the first ten registers, R0 to R9, while Époint2æ contains the values
put into these registers by the swi. Values are placed into the
registers as:
9.2
ptr1->r[0]=reg0_in ;
9.2
ptr1->r[1]=reg1_in ;   etc.
9.2
Values can also be retrieved from the registers,
9.2
reg0_out=ptr2->r[0] ;
9.2
reg1_out=ptr2->r[1] ;   etc.
9.2
ÉCodeæ is the actual swi number. Apec has registered swi numbers for
reading and writing its prototype board; e.g. the value for reading the
podule is 0x80941 and to write it is 0x80940. If the VIA is a 6522, the
clock and read/write pulse must be synchronised, and the swi to do this
is 0x80947. Here is an example of one of the subroutines:
9.2
int aread(int offset) ;
9.2
/* returns a value read from address
9.2
 Éoffsetæ in VIA space */
9.2
{point1 , point2,
9.2
 *ptr1, *ptr2 ;
9.2
int code=0x80941, temp, podno=0,
9.2
 blockno=0 ;
9.2
ptr1=&point1 ; /*relate ptr1 to
9.2
 point1*/
9.2
ptr2=&point2 ; /*and ptr2 to point2*/
9.2
ptr1->r[0]=podno ; /*put podule no.
9.2
 into R0*/
9.2
ptr1->r[1]=blockno ; /*put block no.
9.2
into R1*/
9.2
ptr1->r[2]=offset ; /* Éaddressæ to be
9.2
put into R2 */
9.2
_kernel_swi(code,ptr1,ptr2 ) ; /* call
9.2
 the swi */
9.2
temp=ptr2->r[3] ; /* put the value
9.2
 read into temp */
9.2
return temp ; /* send it back to the
9.2
 caller */
9.2
}
9.2
The last items before the main program are globally used variables and
function names defined outside this program module, but which are used
inside.
9.2
EXTERN
9.2
void afax(void) ;
9.2
char color[16] = {0 xff,0xfe,0xfd,0xfc,
9.2
                  0xd3,0xd2,0xd2,0xd0,
9.2
                  0x2f,0x2e,0x2d,0x2c,
9.2
                  0x03,0x02,0x01,0x00} ;
9.2
Écolor[]æ is a look up table for selecting a shade of grey. It could as
easily be put into the assembler coding. In fact, for this program, the
whole thing could be in assembler.
9.2
The main program
9.2
The main program simply sets up the VIA to give a square wave at one of
its output pins, makes one of its 8 bit ports an input and gives the
control pins suitable logic states. When this is done, the program calls
the assembler part:
9.2
afax() ;
9.2
The assembler program
9.2
This is the exciting part and does all the work! I will not give a Éblow
by blowæ account of what each line of the program does but will
concentrate on the principles. (The whole program is on the monthly
disc, but if you donæt want to pay ú2 just for that, send a blank
formatted disc to NCS and ask for the files.) Three files are É.INCLUDEæ
ones, to avoid writing all the swi name/number and register name/number
equivalents, and one is a macro to find the relative address of a label.
9.2
An É.EXTERNæ statement informs the linker that a number of functions
will be found elsewhere. Two of these are C functions and one is our
look up table. As in the C program, names are used to replace numbers to
aid understanding, and labels, such as ÉVDU_Input:æ or Écoloradr:æ,
represent addresses. For example, to reserve space for the address of
the look up table:
9.2
; anything after ; is a comment
9.2
; all code will be using ÉWingpassæ
9.2
 conventions
9.2
coloradr: .ADDRESS color
9.2
; the actual address of the look up
9.2
 table is put into R4,
9.2
ldr R4, coloradr
9.2
;
9.2
The address of the label, Écoloradræ, will be put into the above
command. Its contents will be transferred to R4, which will be the
address of the look up table Écoloræ, and the linker will find this
address in one of the files it has been instructed to examine in order
to find the externally defined labels.
9.2
The assembler program reads data from the A/D, modifies it, and writes a
value to the screen memory. Since I do not know where the screen memory
starts, SWI ÉOS_ReadVduVariablesæ is used. This swi expects to find a
block of memory starting at ÉVDU_Input:æ listing the numbers of all the
variables whose values are required Ö there are more than 40 of them.
The list is terminated by -1. The address of this block is in R0, and
there must also be a block of memory starting at Édisplaystart:æ to
receive these values. The address of Édisplaystart:æ is put into R1. The
code for the start of screen memory is 149. It is conventional to put
instructions that save blocks of memory before the actual program starts
but they will be concatenated in the example below.
9.2
; reserve space for 3 words of data
9.2
VDU_Input: .LONG 149  ; code for
9.2
 screen start
9.2
.LONG -1              ; end of list
9.2
 marker
9.2
displaystart: .BLKL 1 ; save 1 word
9.2
 for the reply
9.2
;
9.2
ADR R0,VDU_Input      ; address of
9.2
list in R0
9.2
ADR R1,displaystart   ; address of
9.2
 reply in R1
9.2
SWI OS_ReadVduVariables ; call the
9.2
 routine
9.2
; screen start address is now in R1
9.2
Reading the A/D
9.2
The state of the control pin of the VIA which is being used to detect
when a conversion has been completed, must be reset by reading the
output port. When this is done, the program tests the interrupt flag
register to see if the control pin has changed its state, indicating the
end of a conversion. When this happens, a second control pin is set to
logic 0, the output is read and this control pin is reset to logic 1.
These commands ensure that the most recent data is read from the A/D.
The program then continues by modifying this data before storing it in
the screen memory.
9.2
Writing to screen memory
9.2
It will be remembered that only 16 grey levels are available and the
most convenient way of reducing the possible 256 values from the A/D to
16 is to divide by 16! This is easily accomplished by shifting the data
in a register four places to the right. To find the code for the
appropriate shade of grey, we look up the næth element of the look up
table where n is one of the 16 data values. This is done by using an
indexed indirect addressing mode. Suppose that the data is in register
R6 and the address of the look up table is in R9, then the appropriate
value will be put into R6 by using:
9.2
ldrb R6, [R9, R6]
9.2
The values in R9 and R6 will be added and this will be treated as an
address whose contents will be put into R6. This value must be stored in
the appropriate place in the screen memory, and again indexed addressing
is used. This time a byte store instruction must be used and is:
9.2
strb R6, [R4, R5]
9.2
This store instruction works just like the load one but puts the data
into memory. R5 is assumed to contain a counter stating where in a line
the new value must appear. When the value in R5 reaches 639, the
contents of R5 must be reset to zero and the screen base address in R4
must be increased by 640, since there are 640 pixels in a line in mode
15 (the best I can use at the moment).
9.2
You might ask why I did not continue increasing the counter until all
the lines had been filled. The reason is that I wanted the freedom to
use fewer than 640 points per line, which is more easily accomplished by
using this two-stage incrementing scheme. The program continues reading
data and writing it to the screen, until all 256 lines have been used.
Registers which have been stored for safety are restored and control is
passed back to the C calling program.
9.2
Diagnostic comments
9.2
There is a string of commands which have been commented out. These are
there for diagnostic purposes and also show how C functions can be used
in assembler. The registers R0, R1, R2 and R3 are used to pass arguments
to functions which are then called using the Ébranch and linkæ command.
9.2
; an example of the C Éprintfæ command
9.2
; somewhere put these statements
9.2
s1: .ASCIZ   öValue in R5 is%x\nò
9.2
; format in C style
9.2
    .ALIGN       ; ensures that the
9.2
                 ; next command starts
9.2
                 ; on a word boundary
9.2
; now the code
9.2
     ADR R0, s1  ; put address of
9.2
 format statement into R0
9.2
     mov R1, R5  ; we want to see the
9.2
 value in R5
9.2
     bl _printf  ; branch to the
9.2
 routine and come back
9.2
There is no example of the weather map because I do not think that I
have one that is good enough for publication. It is not easy to obtain
perfect maps over the air because of interference and the variable
quality of the transmission. Work is continuing and as improvements are
incorporated, I will report them.
9.2
Any comments? Please write to me at 156 Holmes Chapel Road, Congleton,
Cheshire CW12 4QB.áuá
9.2
Acorn C/C++ and Beebug Easy C++
9.2
Steve Poulard
9.2
C++ being all the rage, Acorn owners finally got their chance to jump on
the bandwagon earlier this year with the release of products from Acorn
and Beebug. Although both support C, C++ and assembler programming, I
was primarily interested in the aspects relating to C++.
9.2
As neither package claims to teach users how to program in C++, a
language reference manual is essential. I prefer ÉThe C++ Programming
Languageæ Second Edition, by Bjarne Stroustrup.
9.2
For this evaluation, I was using an A5000 with 8Mb RAM and a ColourCard.
9.2
Easy C++
9.2
Beebugæs product comes in a small box containing three discs, a 200 page
manual, a 30 page appendix describing the debugger, and a few pages of
release notes. Apart from two third-party libraries, the software is
supplied uncompressed, and installing is a simple process of copying the
files into the directory of your choice, while SysMerge is used to
update the modules in your System directory. The installed files occupy
just under 3Mb of hard disc space.
9.2
The software consists of two main applications ù EasyC++ itself and
EasyDebug, a debugger. There is also a program, Archivist, for
maintaining libraries. ROSLib and DeskLib (a freeware library) are
provided for use with C or C++, while there are a further two libraries
provided specifically for C++. These are C++Lib (the equivalent of Clib)
and Vista, a third-party product, which provides an incomplete class
library for writing Wimp applications. Vista and DeskLib are both
archived, and a copy of SparkPlug is supplied to decompress them.
9.2
To start writing code yourself, a source code editor is required.
Although there is nothing to stop you from using Edit, it makes rather
more sense to get hold of a programmeræs editor that supports throwback,
such as Zap. If you want to go further and develop Wimp applications, a
template editor (i.e. FormEd) is almost essential.
9.2
Although there are a few applications supplied with DeskLib and Vista,
the examples are all rather trivial.
9.2
Program development
9.2
All aspects of program development (other than debugging) are controlled
from EasyC++. The main window contains two scrolling lists for source
and object file names, five buttons ù labelled ÉCompileæ, ÉLinkæ,
ÉStopæ, ÉCreateæ and ÉMakeæ ù and a few text icons containing status
information. Using the window menu and a setup dialogue box, a number of
options can be set, the most significant of which is whether the
language used is C or C++. Amongst the other options, you can select the
libraries to include and produce code for debugging.
9.2
With the default options, building a program from a single source file
is a simple matter of dragging a file to the source file scrolling list,
clicking on ÉCompileæ then ÉLinkæ. For more complex program development,
the ÉCreateæ button can be used to automatically generate a makefile
from a list of source files. Alternatively, for those with masochistic
tendencies, makefiles can be edited by hand. Makefiles are text files
and must be dragged to the iconbar to load.
9.2
According to the release notes, the C++ compiler conforms to the
language definition in Stroustrupæs book, with a few problems and
limitations. However, even within a few minutes of starting, I
discovered an omission not mentioned in the release notes ù after trying
to cin and cout a long double variable, Iádiscovered it was not defined
in the header file for the IOStream library.
9.2
Overall, this application provides all the features I was expecting, and
is simple and intuitive to use, with only a few niggles. For example,
the main window doesnæt tell you whether you are in C or C++ mode; both
C and C++ source code should be placed in a directory called ÉCæ; and a
Édebugæ directory needs to be created by hand before debug files can be
produced.
9.2
Libraries
9.2
The most interesting of the supplied libraries are ROSLib, DeskLib and
Vista. ROSLib and DeskLib are C libraries, although they can be used
with C++.
9.2
ROSLib provides a basic range of functions for graphics commands
(changing mode, moving, drawing and plotting etc) and for SWI calls
(os_byte, os_word and os_swi).
9.2
DeskLib is a freeware library and comes with a note stating that there
are unlikely to be any future releases unless someone takes it over from
its current compiler. It provides a large number of functions grouped
into about fifty categories, which include SWI veneers (e.g.
PrinterDriver, Font, Wimp), functions for handling Wimp objects
(windows, icons, menus, events, dialogue boxes etc) and other general
purpose functions (such as linked lists). Some of the individual
categories do not provide much functionality. For example, the sound
handler contains a single function that writes a character 7 to the VDU
stream. Beep!
9.2
Vista is a third-party product intended for writing Wimp applications,
and is also the only library written specifically for C++. It is based
around three complex classes ù ÉTaskæ, ÉWindowæ and ÉIconæ.
Incidentally, the examples provide the only decent illustrations of C++
programming in the whole package. This is a well thought-out product
which appears to have been written by one person. I only hope he is able
to develop this resource further.
9.2
Debugging
9.2
To use the EasyDebug application to the full, a program should be
compiled and linked with the debug option selected, in which case, the
executable code is given a special filetype. A debugging session can be
started by double-clicking on one of these files. The debugger will work
with ordinary files, but only at object code level.
9.2
When a debug file is loaded, two windows are opened ù a task window for
showing output from the program, and the main control window. This
contains: a list of source files used to build the application, a stack
trace, a list of breakpoints and a number of buttons along the bottom
which control program execution. Clicking on a source filename opens a
window showing the source code by line number (and/or address). Double-
clicking on a line of code adds a breakpoint at that point ù shown in
the source code by a black spot, and appearing in the breakpoint list in
the main debugger window.
9.2
Clicking on the Run button runs the code to the breakpoint, and opens
another window listing the local and global variables. Clicking on one
of these variables opens yet another window which displays its value and
allows that value to be altered. If the variable is a pointer or a
structure, double-clicking on it de-references it so that, for example,
the structure is displayed. If the variable is an array, the index value
can be edited to see all the individual elements. Once opened, these
windows persist to the end of the session. Program execution can be
continued, or single-stepped through the source code.
9.2
In common with most debuggers Iæve used, breakpoints can be conditional,
and can have before and after execution commands specified. A breakpoint
can also be turned into a watchpoint, which updates the displayed
variable values but doesnæt halt program execution (although it does
slow it down a lot). It is also possible to set breakpoints for specific
variable values.
9.2
Once the program has finished, it can be re-run, which opens a second
task window. I had problems trying to change or add breakpoints after
the first run. In order to debug another application, it is necessary to
quit the debugger and load another debug file from scratch ù which
starts another task window, but doesnæt remove any previously opened.
After a few sessions, it is quite easy for the desktop to become rather
cluttered.
9.2
There is also a profile window which shows the time taken for different
functions to execute (this requires code to be compiled with this option
on). There is also a memory editor window for displaying and editing the
contents of the registers and memory directly.
9.2
In general, the use of persistent windows makes this a very friendly
debugger to use. It works equally effectively with programs produced
from C and C++ code (but keep on reading!).
9.2
One very important aspect of the debugger is that it is multitasking.
This is good news when debugging non-Wimp programs, as it enables the
use of the different windows, and means you can still use your favourite
text editor. As admitted in the manual, the problem comes when debugging
Wimp applications, as the desktop has not been designed to cope with
stepping through a running program. The manual warns that the program
might not behave as it would outside the debugger. In practice, I found
it rather easy to crash Wimp programs when debugging them.
9.2
Another difficulty is in running a program when it is part of an
application. Assuming it is written as a standard application with
!Boot, !Run, !RunImage, Template files etc, it is not possible to run it
by double-clicking on the application directory as normal. Double-
clicking on the !RunImage (debug file) may not work either, as !Run will
usually set up a number of environment variables. In the example, Iáwas
debugging, I found that double-clicking !Run (which produced an error)
and then debugging !RunImage worked, although this might not always be
the case, depending on how much !Run does.
9.2
Documentation
9.2
I did not have any problems understanding the manual, which starts with
a gentle introduction to compiling and running a simple program (the
ubiquitous ÉHello Worldæ) in six easy steps. Unfortunately, it then
recommends the user compile three further examples, one of which
produces 20 compilation warnings, and one of which doesnæt link unless
the default settings are altered. Although changing the settings is a
comparatively trivial task, this is not dealt with until later, which is
unacceptable for a chapter called ÉGetting startedæ. The manual then
briefly describes how to use EasyC++, which is followed by an
introduction to C from the point of view of someone familiar with BBC
Basic. Most of the rest of the manual is taken up with a description of
some ANSI and all the ROSLib functions.
9.2
The main drawback with the documentation is that it is for Easy C rather
than Easy C++, and thus ignores all the features which relate
specifically to C++. Fortunately, the changes are obvious enough that
they are annoying rather than a problem. I donæt know if a new manual
has yet been produced.
9.2
Acorn C/C++ costs ú230 through Archive and Beebugæs Easy C++ is ú110
through Archive.áuá
9.2
This is only the first half of the article, which is rather long, so if
you want to read the second half of Steveæs review dealing with Acorn C/
C++ and the conclusion, it will be in next monthæs issue. (If you canæt
wait, look on the Archive monthly disc!) Ed.
9.2
A Tale of Three Stacks
9.2
Richard Bradbury
9.2
Over the summer, there has been a quiet revolution in communications on
RISCáOS machines. Internet on the Acorn has at last come of age.
However, the product responsible is no commercial offering: as its name
suggests, FreeNet wonæt cost you a penny.
9.2
In the beginning
9.2
For the past couple of years, Acorn users have been using a package with
the peculiar name ÉKA9Qæ to communicate with Internet. Ported from the
PC package of the same name, KA9Q is best described as a Swiss Army
Knife. It will automatically download your mail and news when you log
on, it allows you to conduct interactive Telnet terminal sessions, and
even offers file transfer facilities.
9.2
Two years ago, KA9Q was a pretty basic program, but since then it has
sprouted a fancy user interface and will scatter multiple windows across
the desktop given half a chance. There is plenty of supporting software
too: news readers, like TTFN, and World Wide Web browsers, like ArcWeb
and Webster.
9.2
The only trouble with KA9Q is that it is an Éall or nothingæ approach to
communications. You canæt just get rid of the mail and news parts of the
program once you have finished with them.
9.2
Divide and conquer
9.2
What makes FreeNet different is that it splits the complex structure of
a complete Internet stack into a number of simpler units. These can then
be coded and tested separately. Also, because each unit has a well-
defined interface, the whole thing can be assembled as a hierarchy Ö the
stack Ö with the confidence that it will all work. Well, thatæs the
theory; in practice there are always bugs, but extensive testing and
feedback to the author has shown FreeNet to be a very stable piece of
software.
9.2
The figure shows the FreeNet stack in comparison with KA9Q and Acornæs
own TCP/IP Internet stack. As can be seen, the FreeNet module is a
direct replacement for Acornæs Internet module. Indeed, FreeNet loads a
dummy version of the Internet module, partly to fool programs which
expect to find Internet, and partly to overwrite the module if it is
already loaded, since the two stacks cannot co-exist.
9.2
The setup illustrated is a typical one, using the SLIP protocol. This is
a simple link protocol which enables the IP packets generated by FreeNet
(or Internet) to be sent down a serial line, either to an Internet
provider via a modem, or directly to another computer via a Énull modemæ
cable.
9.2
Notice that, unlike Gnomeæs offering for the Acorn stack, FreeNetæs SLIP
driver talks to the serial hardware indirectly through Hugo Fiennesæ
serial port block drivers. This means that FreeNet can use third party
serial interfaces as well as the standard Acorn serial port. It also
means that you can use standard PC modem cables rather than the
decidedly non-standard Acorn wiring convention.
9.2
Of course, being modular, FreeNet will allow you to substitute any
suitable hardware driver in the place of SLIP. This may be the driver
supplied with your Ethernet card (either on the cardæs ROM or on disk).
Under development at the moment is a PLIP driver for fast parallel port
links. Another possibility is the more complex PPP (point-to-point
protocol), which many Internet providers are now supporting. The reason
why this Émix and matchæ approach works is thanks to Acornæs DCI
specification.
9.2
DCI what?
9.2
The Acorn Driver Control Interface is simply a standard for writing
device drivers. As long as the driver complies with the DCI
specification, it can be used by any DCI compliant stack.
9.2
Unfortunately, there is a fly in the ointment. With the advent of the
Risc PC, Acorn moved from revision 2 of DCI to revision 4. Up until now,
most Ethernet interfaces have been built to the DCI-2 specification.
However, the new ÉEtherBæ cards for the Risc PC (developed by Acorn and
ANT Ltd.) comply with DCI-4. To keep up with the hardware, the software
has been updated too, and Acorn now supply a DCI-4 Internet module in
the RISC OS 3.60 ROMs.
9.2
The bottom line for FreeNet users is that they will be unable to get it
to work with the Risc PC Ethernet card because FreeNet is a DCI-2 stack
and is unable to drive DCI-4 devices. There is light at the end of the
tunnel, though, because work is underway on an all-new DCI-4 version of
FreeNet. Of course, this has no bearing on SLIP users, since the DCI-2
SLIP driver can be Ésoft-loadedæ, even on a Risc PC.
9.2
Plugs and sockets
9.2
The DCI specification is actually only half of the story because a
protocol stack is only as good as its programming interface. When it
comes to Internet stacks, there is only one real choice: Berkeley
Sockets.
9.2
The Sockets interface was defined in the mid eighties by a research
group at the University of California who were developing networking
software for Unix machines. Sockets provide the programmer with a set of
high-level routines for manipulating TCP connections. He can open a
connection to a remote host and exchange data with it (a so-called
Éclientæ). Alternatively, he can wait for other people to connect to his
host and then do some processing on their behalf (a Éserveræ).
9.2
This client-server paradigm is at the heart of Internet communications.
Clients and servers exchange information according to a particular high-
level application protocol (such as SMTP for mail, NNTP for news or HTTP
for hypertext Web pages).
9.2
Under Unix, Sockets are built into the operating system and the
programmer simply includes a couple of standard header files with his
ÉCæ source. With the Acorn stack, the routines are implemented as SWIs
in the Internet module (which is largely based on the Berkeley source
code). The names of the SWIs bear a striking resemblance to their Unix
counterparts, too. The Éconnectæ call, for example, maps to ÉSocket_
Connectæ on the Acorn. Even the parameters match exactly Ö they are
simply presented in registers R0, R1, R2 and so on. Also, the FreeNet
module, being a straight replacement for Acornæs Internet module, offers
exactly the same interface to programmers.
9.2
Of course, programming using the SWIs directly is possible, but not for
the fainthearted. What is really required is a library which provides
the same functions available in the Unix header files. This would enable
software to be ported directly to the Acorn platform with only minor
modifications. Indeed, Acornæs now-discontinued TCP/IP Programmeræs Pack
provided such a library. Not to be outdone, FreeNet has its own
companion Sockets library, called NetLib.
9.2
Applications galore
9.2
Acorn supply the now infamous VT220 terminal emulator with their TCP/IP
product. It provides the user with an adequate interface to Telnet, but
it is the worst implementation of an FTP client I have seen. There is
also the recently released mail and news suite, InterTalk, although this
is aimed squarely at the education market rather than the individual.
Users requiring more bells and whistles will have to wait for the ANT
Internet Suite, available now in beta-test form, but not quite ready for
full release.
9.2
Seeing a rather large niche in the market, the FreeNet developers have
produced a wide selection of clients and servers, all available for the
price of a download. There are a number of standalone mail and news
programs, a sockets-based add-on for NewsBase, a terminal emulator
called FreeTerm, a proper command line FTP client and a wide selection
of servers which allow other people to log into your machine when it is
on-line Ö and donæt forget the freeware Web browsers which can fetch
pages over the Internet. There is also a plethora of programming
libraries and code fragments available which will help the budding
programmer to get started.
9.2
Stop press!
9.2
With the release of FreeNet in May, Acorn Internetters breathed a sigh
of relief. At last a freeware Internet stack to rival the pricey Acorn/
Gnome alternative. FreeNet had a promising future with a large number of
users actively working on applications for it. But then, in July, Acorn
threw a spanner in the works by releasing its own DCI-4 stack on a free
basis. So where does this leave FreeNet?
9.2
Well, FreeNet is still the only stack which includes a SLIP driver for
nothing. Moreover, Acornæs free stack includes none of the applications
supplied with the commercial version Ö not even VT220. The FreeNet
project has also served as a catalyst for new software development in
the networking and communications arena. Also, because standard
interfaces have been adhered to throughout, any software designed to
work with FreeNet will almost certainly work equally well with the Acorn
TCP/IP stack or even ANTæs forthcoming product.
9.2
At long last, Acorns across the land can move out of the slow lane on
the Global Superhighway.
9.2
How to get it
9.2
The FreeNet archive is maintained at two separate sites, the first at
the University of Southampton (for JANET users), and the other on Demon
Internetæs FTP server (for other users).
9.2
cslib.ecs.soton.ac.uk in directory /pub/Acorn/freenet.
9.2
ftp.demon.co.uk in directory /pub/archimedes/developers/freenet.
9.2
The file Ésoftware-indexæ is an automatically generated index of what is
available. The latest version of the FreeNet stack itself (including the
SLIP driver) can be found in the subdirectory Ét.hughesæ.
9.2
Contacts
9.2
Correspondence relating to FreeNet should be sent to
[e-mail], or to the author, Tom Hughes, at 5 Lampits,
Hoddesdon, Herts EN11á8EH.
9.2
Information about the current status of FreeNet can be obtained by
sending a blank message to [e-mail] with the subject
field ÉSEND freenet.infoæ.
9.2
I can be contacted as [e-mail].áuá
9.2
Jargon Buster!
9.2
If you are struggling with some of the jargon associated with the
Internet, Archive has come to the rescue(!) by providing a glossary Ö
which includes contributions from Richard Bradbury. The Archive Internet
Glossary is too large to publish in the magazine Ö 12 pages, 6,000 words
and rising Ö but it is available on the Archive Glossary Disc (priced at
ú5) which also contains our main Archive Glossary Ö 19 pages, 11,000+
words. If you would prefer a printout of these glossaries, they are
available as the Archive Glossary Booklet, also at ú5.
9.2
Three Internet stacks: KA9Q (left), Acorn TCP/IP (centre), FreeNet
(right).
9.2
Optical Mice
9.2
Richard Simpson
9.2
Fed up with cleaning the rollers on your mouse? Slowed down by a
recalcitrant rodent? There is a better way Ö get an optical mouse and
say goodbye to balls. öA mouse with no ball? Impossible Sir!ò
9.2
Itæs not impossible!
9.2
Last monthæs Archive contains an excellent article by Richard Torrens
describing how ordinary mice function. If you are not familiar with the
inside of your mouse, I suggest that you read Richardæs article before
proceeding.
9.2
An optical mouse has no ball. Instead, it uses a special mat covered in
small dots. As the mouse moves, a chip underneath the mouse watches the
dots go by and sends the relevant signals to the computer. Optical mice
have no moving parts (except the switches) and are therefore extremely
reliable. They have NO rollers to clean.
9.2
If you rapidly accelerate an ordinary mouse, the ball can skip and the
pointer may not move as far as you had hoped whereas optical mice
faithfully reproduce any movement. Many people will not notice this
improvement, but fast mouse users will find optical mice more
responsive. In a similar way, a high quality keyboard which would be a
godsend to touch typists will not be of benefit to Éhunt and peckæ
typists.
9.2
öIf they are so wonderful, why have I never seen one?ò Well, itæs a bit
of a mystery. Optical mice are very rare in PC land, but much more
common on Unix workstations. Indeed, they have been standard on
SPARCstations for several years. They are relatively expensive, but my
guess is that people stick with ordinary mice for the same reason that
they still use PCs (i.e. öI want the same as everyone elseò.)
9.2
Drawbacks? Well, apart from the price and the fact that no-one makes
them to fit Acorn computers, it is necessary to keep the sides of the
mouse reasonably parallel to the sides of the mat. My friends and
colleagues have had no problems, but I have no experience of how
children cope with them, and it may be that the very young or those with
a disability could have difficulty with them.
9.2
Beware of suppliers who claim to be selling öopto¡mechanicalò mice. This
is the technical name for an ordinary ball-based mouse. Another phrase
to avoid is ösemi¡opticalò. If you are not sure, phone and ask if the
mouse has a ball. If they say öYes, obviously, Sir. All mice doò then
you need to go elsewhere.
9.2
Converting an Atari mouse
9.2
Golden Image produce optical mice for a number of different computers,
including the Atari ST and the Amiga. They generate exactly the same
electrical signals as an Acorn mouse, so all that is required to convert
them is a suitable adaptor. The Atari versions come with a 9 pin D-type
connector and the table below shows the adaptor required. Alternatively,
you could cut off the D-Type and fit a new connector or let Paul sell
you a complete new mouse lead. (Not cheap, I fear, because they are
Acorn spares Ö the cheapest is ú11 through Archive. Ed.) For details of
the Acorn mouse connector, consult your manuals.
9.2
Suitable connectors are available from Maplin for about 90p (part
JX19V). Be warned that they are very fiddly, and unless your soldering
and eyesight are good, a new cable may well be the best solution.
9.2
The Golden Image mouse is reasonably well made (although a little slim
for my liking), but it provides a somewhat coarse resolution and its
mouse mat leaves something to be desired. It has a rubber construction
very much like a conventional mat but the top surface tends to peel and
generally disintegrate. After four years of use, mine is now in a sorry
state. The mat is also inclined to stick to your hand. The supplier
which I used no longer sells them, but if you get a copy of Atari
Monthly (or some such) you may be able to locate a source.
9.2
Mouse Systems PC Mouse III
9.2
Mouse Systems is a US manufacturer who produce a number of mice,
including an optical version called the PC Mouse III. This is a mouse of
exceptional quality which provides nearly twice the resolution of the
Golden Image, excellent ergonomics and a virtually indestructible metal
mouse mat. I have used one at work for three years and consider them
superior to the mice provided with SPARCstations.
9.2
After that build¡up, you will not be surprised to hear that there is a
downside. Apart from being one of the most expensive mice that money can
buy, they are only available as PC serial mice. öWhatæs a serial mouse?ò
Read on!
9.2
Ye olde mouse
9.2
Back in the mists of time when mice were first invented, computers
didnæt have mouse ports. Now, reading Richard Torrensæ article, it
should be clear that an Acorn mouse port consists of 7 digital input
lines and a 5V supply. The electronics required for this is very simple
and I seem to dimly recall connecting my BBC mouse to the user I/O port
Ö werenæt BBCs versatile?! Most manufacturers chose to add such simple
mouse ports, but with the limited exception of Ébus miceæ, the PC world
chose instead to use one of the serial ports. This was achieved by
installing a simplified UART into the mouse and encoding details of
mouse movement and switch operation into bytes which were sent down the
serial line. The required positive and negative supplies were sniffed
from the portæs output pins. Thus, at a stroke, the mouse was made
significantly more complicated. The PS/2 compatible mouse ports, fitted
to many modern PCs, are little more than simplified serial ports. They
provide proper supply lines, but the principle is the same. Now, all
this made some sort of sense ten years ago, but Ö like DOS Ö its
continued use on modern computers defeats me.
9.2
öSo that last half page was just a long-winded way of telling me that I
cannot connect this wonder mouse to my Arc then?ò. Well actually no,
there are two possible solutions which I shall now reveal.
9.2
Solution 1 Ö The easy way
9.2
The name of Mouse Systems may be vaguely familiar to those of you with
RiscáPCs. If you click on the öMouseò option in Configure you will see
the dialogue shown below.
9.2
Choose the Mouse Systems option, plug in your PCáMouseáIII and away you
go. The only drawback, of course, is that it ties up your serial port.
9.2
If you do not have a RiscáPC, you need to obtain a copy of Stuart
Tyrrellæs !SerialMse application. This neat piece of code allows you to
connect a PC mouse to your serial port and it seems to work fine with
the PC Mouse III. (!SerialMse is on this monthæs Archive disc. Ed.)
9.2
Of course, one of the few significant problems with Acorn computers is
the appalling decision to provide only one serial port. How are we to
Ésurf the netæ if our mouse is connected where the modem would normally
go?
9.2
Solution 2 Ö Surfæs up!
9.2
It is possible to modify a PCáMouseáIII to fit the standard Acorn mouse
port. Needless to say, this will invalidate any warranty on the mouse.
9.2
To see how the modification might be achieved, consider the block
diagram below which shows the internal working of a PCáMouseáIII.
9.2
The important fact here is that the seven lines entering the left side
of the UART are exactly the same as the lines running up the cable of an
Acorn mouse. So all we need to do is tap into these wires by soldering
onto the pins of the chip. The 5V supply can be introduced at any
convenient point after the level converter.
9.2
The photo opposite shows the general layout of the PCáMouseáIII after
modification. I reused the cable from my original Acorn mouse but, as
mentioned earlier, Paul will be happy to sell you a new mouse cable. The
optical sensor is beneath the ribbon cable in the centre and the cable
to the computer normally terminates at the connector in the foreground.
The switch on the right selects between 2 and 3 button mode. Obviously
É3 buttonæ should be selected (although, after modification, it makes no
difference).
9.2
On the older version which I have at work, the empty space in one corner
of the circuit board contains a 555 timer and several discrete
components. I am not sure what these do since they are clearly not
essential. I suspect that they form a charge pump to generate the
required negative voltage, and that Mouse Systems have now found that
they can reliably tap this voltage from the serial port. I have not
tried to convert a mouse with these extra components, but I donæt see
why it shouldnæt work.
9.2
The next diagram shows the UART pins of interest to us. The numbers
indicate the relevant Acorn mouse connector pins.
9.2
The power supply is connected to VR1, a 5.2V zener. Ground and the cable
screen should be connected to the end nearest the buttons.
9.2
The final photograph shows a close¡up of the finished modifications. The
level of soldering skill required is not high, but I wouldnæt recommend
beginners to attempt it. Putting the top back on the mouse may well be
the hardest part of the modification. I canæt describe how itæs done Ö
youæll just have to develop the knack like I did! Suffice it to say that
it needs more force than you might think.áuá
9.2
Beginnersæ Corner
9.2
John Temple
9.2
I am responding to our hard-working editor who made a plea for some non-
programming contributions, especially for some Ébeginners-typeæ
articles.
9.2
I shall assume that you, the reader, know nothing, but I will take you
gently as deep as I can. The sorts of things I have in mind to cover in
this series are: RISCáand RISC OS, Displaying Text on Screen, Editing
and Formatting, Fun with Draw, Sprites and Paint, Animation, Alarms,
Music Technology.
9.2
After that we shall have to see where to go next, if anywhere. If
thereæs anything you would particularly like covered, please ask Paul.
But remember, this is meant to be for beginners. Oh, by the way, I am a
teacher by profession, so I may attempt to keep you on your toes by
asking questions. Donæt worry, Iæll also give you the answers.
9.2
RISC and RISC OS
9.2
Youæve heard of Computer Architecture? It is just a posh way of saying
what a computer is made of. Different computers have different
architectures but they all must have five essential components: a
central processor or processing unit (CPU for short), input and output
devices, memory and backing store.
9.2
Everything that happens in a computer is controlled by the CPU. All the
other components are connected to it. The BBC computer has one called a
6502. PCs have a 286 or a 386 or a 486, depending upon how old they are.
Acorn computers gain their superior speed and simplicity with a
processor called RISC, which stands for Reduced Instruction Set Computer
and the processor is driven by an operating system (OS) which resides in
the read only memory (ROM).
9.2
So now you know what RISC OS means, but there are several versions of
the operating system. If you want to know what version you have, move
the blue pointer (by using the mouse) so that it is over the icon
(little picture) at the bottom right of your screen Ö an acorn if you
have version 3 or later, or an ÉAæ if itæs version 2.) Press the middle
(or menu) button of the mouse, and a menu will appear. Move up to the
top item, Info, and guide the pointer over the arrow. There you have the
answer.
9.2
Displaying text on screen
9.2
Letæs now move on to what RISC OS has to offer. One of the most
important pieces of software that comes with it is an application called
Edit which is used for editing text. It is less sophisticated than a
word processor but what it does, it does fast Ö and Iámean fast. You can
drop edited text into a word processing package. You can drop it into
other applications such as Draw (RISCáOSæ own drawing package) and even,
if you have RISC OS 3 or later, write a program with it.
9.2
The best way to find out how it works is to try it. You will need to
have the application loaded onto the iconbar and you will need a file
(containing some text) to practise on.
9.2
If you have RISC OS 3.10 or later, you load Edit by clicking the left
hand mouse button (select) on the Apps icon on the iconbar and then
double-clicking on the Edit icon in the window which appears.
9.2
If you have an earlier version of RISC OS, you have to load Edit from
the Applications disc which came when you bought the computer. Put it
into the disc drive and click on the floppy drive icon and double-click
on the Edit icon in the window which appears.
9.2
The file we shall use is called OneTo50. Iæm afraid the text is a bit
boring but it has the virtue that you know exactly where you are within
it, all the time. It is simply, One, two, three, four, five, ..... etc
..... all the way up to ... forty eight, forty nine, fifty. If you have
the monthly disc, click on the floppy drive icon and then double-click
on the Beginners icon.
9.2
If you donæt subscribe to the disc, start typing!
9.2
You may like to click on the toggle size icon to give yourself a full
screen. When you have finished typing, reduce the size again by dragging
adjust size or clicking in toggle size. When you have finished typing,
save it!
9.2
To do this, open a filer window (i.e. double-click on a suitable
directory). With the pointer over this window, press the menu button and
move the pointer over the Save arrow on the Edit menu which appears:
9.2
(If you have RISC OS 3, there is a shortcut for this Ö press <F3>.)
9.2
Now drag the ÉTextFileæ icon (or ÉOneTo50æ icon if you loaded it off the
disc) into the directory window.
9.2
Now that you have got the file up on the screen, press the menu button
and explore the Display menu.
9.2
I suggest you try to find out...
9.2
(1)áthe differences (apart from size) between the fonts (Corpus,
Homerton and Trinity);
9.2
(2)áwhat you must do to display text in Homerton bold oblique, using
size 20;
9.2
(3)áhow to make the letters red and the background yellow;
9.2
(4)áhow to make the left hand margin wider or narrower;
9.2
(5)áwhat Wrap does;
9.2
(6)áwhat Invert does.
9.2
Did I say the questions would be easy? Iæll tell you the answers next
time. Weæll also see how to mark, move, copy, delete and format text.áuá
9.2
Ideal for beginners is the Archive Glossary (17,000+ words of
explanatory text). It is available for ú5 as a booklet and/or ú5 in
(upgradable) disc form Ö details in Products Available. Ed.
9.2
C++ Column
9.2
Tony Houghton
9.2
This monthæs article is about overloading, a way of defining groups of
functions, or even operators, with the same name, performing similar
functions, but on different types of data. C++ obviously cannot enforce
that overloaded functions and operators should behave similarly to each
other, so overloading, like much of C++, is open to some degree of
abuse. Avoid defining new meanings for functions or operators which are
not logical and/or similar to existing meanings.
9.2
Please note that in the example program fragments, Iáwill sometimes
introduce methods (i.e. member functions) with definitions and sometimes
with declarations. You should be aware of the difference and know how to
provide a declaration to match a definition and vice versa (see Archive
8.12).
9.2
The term Éargumentæ refers to a variable passed to a function as seen by
the function being called. ÉParameteræ refers to a variable as seen by
the expression calling the function. Just to confuse you, an alternative
term for argument is Éformal parameteræ (as used in compilation error
messages).
9.2
Function overloading
9.2
Overloading functions is as simple as just declaring/defining more than
one function happening to have the same name. The rules are that each
overloaded function must have different types of arguments from other
functions with the same name; you cannot declare functions which differ
only in their return type, because the compiler would not know which one
to call when called without using its return value:
9.2
void sort(int);
9.2
void sort(float);
9.2
void sort(char);
9.2
int sort(int);  // error: sort(int)
9.2
                // already declared
9.2
Each of these functions must be defined separately. There is not really
any more to say about function overloading Ö itæs as simple as that.
9.2
Class member function overloading
9.2
Overloading member functions is as easy as overloading ordinary
functions:
9.2
class String {public: 9.2
  int find(char);
9.2
  int find(char *);
9.2
};
9.2
Constructors are a slightly special case, it is common to provide a
default constructor, either with no arguments or with whatever arguments
are needed to construct an object, and a copy constructor. For a class
X, a copy constructor is declared as:
9.2
  X(X &);  // (within Xæs definition)
9.2
X(X) is not allowed. A copy constructor can be used as part of a
solution to the problem (caveat) I described in Archive 8.12. To recap,
for a class such as:
9.2
class Array {{ Style öArcSymbolò Off}
9.2
  int size;
9.2
  int *array;
9.2
  // ...
9.2
public:
9.2
  Array(int num_elements);
9.2
  ~Array()
9.2
  {delete[] array; }
9.2
  // ...
9.2
};
9.2
the following program will be passed by the compiler, but will crash at
run-time:
9.2
int main()
9.2
{array1(100) ;
9.2
  Array array2 = array1;
9.2
  // ...
9.2
}
9.2
This is because the default copy operation is a member-wise copy, so
array2 will have the same values of size and array as array1. When the
objects are deleted, both array1.array and array2.array are deleted. As
they both point to the same data, this is a potential crash.
9.2
A copy constructor to solve this would be (ignoring error-checking):
9.2
Array::Array(Array &original)
9.2
  : size(original.size)
9.2
{new int[size];
9.2
  if (array)
9.2
    memcpy(array, original.array,
9.2
           size * sizeof(int));
9.2
}
9.2
Now each copied object will be given its own distinct copy of the data.
The class isnæt quite safe yet, copying an Array to an already existing
Array will cause the same problem as before. See below for the cure.
9.2
Destructors never take arguments, so obviously they cannot be
overloaded.
9.2
Operator overloading
9.2
If you had a class representing a mathematical type such as complex
numbers or matrices, it would be convenient to be able to use
mathematical operators such as + or * with them, instead of having to
use functions called add() and multiply(). C++ allows just that with
operator overloading. The operators which can be overloaded are:
9.2
+  Ö*  /  %  ^  &
9.2
|  ~  !  =  <  >
9.2
+=  Ö=  *=  /=  %=  ^=  &=  |=  <<  >>  <<=  >>=  ==  !=  <=  >=  &&  ||
++  ÖÖ  Ö>*  ,  Ö>  []  ()  new  delete
9.2
The last five are not as straightforward as the others, each will be
described separately. Operators which cannot be overloaded are:
9.2
.  .*  ::  ?:  sizeof
9.2
# and ## are not operators, but preprocessor directives, so they cannot
be overloaded either. It is not possible to add completely new operators
or change the number of operands needed by an operator (e.g. you cannot
define a unary /). Operators which can be either unary or binary, such
as Ö, can be overloaded as either.
9.2
Operators cannot be redefined to have new meanings for existing types or
for pointers; an overloaded operator must take at least one class or
reference to class argument, or be a member function of a class.
9.2
=  []  ()  Ö>
9.2
can only be overloaded as non-static class members, because their first
operands need to be lvalues.
9.2
=  &  ,
9.2
already have meaning when applied to classes, so as an alternative to
overloading them, it is possible to declare them as private members (no
definition is needed) to restrict unintentional use.
9.2
Operators need not have the same relationships with each other, e.g.
a+=b meaning the same as a=a+b. However, you are strongly advised to
keep these relationships where appropriate.
9.2
Operator function notation
9.2
An operator function is represented by a function with the name operator
followed by the operatoræs symbol. For unary operators (e.g. !), the
object it acts on is the operator functionæs only argument, for binary
operators (e.g. /) the object before the operator is the functionæs
first argument, and the object after the operator its second. In either
case the result of the operation is given by the function return value.
To illustrate this with an incomplete class for complex numbers:
9.2
struct Complex {{ Style öArcSymbolò Off}  float re, im;
9.2
};
9.2
Complex operator+(Complex a,
9.2
                  const Complex &b)
9.2
// a is local, so no need to define
9.2
// temporary variable for result.
9.2
// b is reference for efficiency;
9.2
// a temporary need not be created
9.2
// if it is passed an actual Complex
9.2
{+ = b.re;
9.2
  a.im += b.im;
9.2
  return a;
9.2
}
9.2
Complex operatorÖ(Complex a)
9.2
// One argument, so unary minus
9.2
{Öa.re ;
9.2
  return a;
9.2
}
9.2
These operator functions can now be called with either notation:
9.2
Complex c = a + b;
9.2
Complex c = operator+(a, b);
9.2
Both are equivalent to each other; the second form is rather rare: why
make a function an operator if youære not going to use it as one?
9.2
Operators as class members
9.2
An alternative to stand-alone operator functions is to make them class
members. In this case the first operand for binary operators, or the
only operand for unary operators, is replaced by the object the operator
is called for. The Complex example becomes:
9.2
class Complex {re , im;
9.2
   // Much safer as private
9.2
public:
9.2
  Complex(float r, float i = 0)
9.2
    : re(r), im(i)
9.2
  // Copy constructor unnecessary,
9.2
  // default member-wise copy is OK
9.2
  Complex &assign(float r, float i)
9.2
  // Needed because member operator=
9.2
  // can only take one argument
9.2
  {r ;
9.2
    im = i;
9.2
    return *this;
9.2
  }
9.2
  Complex operator+(Complex b)
9.2
  // This time b is not reference to
9.2
  // allow local copy to be modified.
9.2
  // a is replaced by Éthisæ object
9.2
  {+ = re;
9.2
    b.im += im;
9.2
    return b;
9.2
  }
9.2
  Complex operatorÖ()
9.2
  {is needed, because
9.2
    // Ö should not actually alter
9.2
    // Éthisæ object
9.2
    Complex b(Öre);
9.2
    b.im = im;
9.2
    return b;
9.2
  }
9.2
};
9.2
When deciding whether to define an operator as a stand-alone function or
a class member, the rule of thumb is to always use a member unless you
have a good reason not to do so. One exemption would be an operator
which acts on two classes, being associated to neither class more than
another. Additionally, the compiler can make no assumptions as to
whether an operator is associative, so if you had a class X with
XáX::operator+(int) you could type x+1 but if, for some strange reason,
you absolutely needed to be able to reverse the order of operands and
type something like 1+x you would need:
9.2
inline X operator+(int a,áX x)
9.2
{x+a ; }
9.2
which is not a member.
9.2
User-defined type conversion
9.2
Complexæs constructor gives us a way of creating a Complex from any type
which can be implicitly converted to float. Furthermore, if you attempt
to assign a float (or other arithmetic type) to an already existing
Complex, the compiler will create a temporary Complex from the float,
before assigning it to the existing Complex. The following mini-program
is therefore correct:
9.2
int main()
9.2
{= 1;
9.2
    // 1 converted to float (at
9.2
    // compilation, not at run-time),        // float passed to Complex
9.2
    // constructor
9.2
  Complex b = a;
9.2
    // Standard copy-construction
9.2
  a = b;
9.2
    // Standard member-wise copy
9.2
    // operation
9.2
  a = 2;
9.2
    // 2 converted to float, passed
9.2
    // to Complex constructor to
9.2
    // create temporary which is then
9.2
    // copied to a
9.2
}
9.2
If run-time efficiency is more important than simplicity of class
design, you can avoid the creation of a temporary Complex during
assignment by a float etc by overloading = :
9.2
  // (within Complex definition)
9.2
  Complex &operator=(float r)
9.2
  {assign(r , 0); }
9.2
Going back to the bugged Array class, overloading = completes the
protection against repeated deletion:
9.2
Array &Array::operator=(Array &a)
9.2
{array ;
9.2
  array = 0;
9.2
  size = a.size;
9.2
  if (a.array)
9.2
  {new int[size];
9.2
    memcpy(array, a.array,
9.2
           size * sizeof(int));
9.2
  }
9.2
}
9.2
In some circumstances, you may wish to convert a class to a simpler
type. This can be done by using one of the type conversion operators,
which are defined as operator <type name>(). No return type is declared
Ö this is implicitly the type name used as the operator. As an unlikely
example, you might want to simplify the notation for taking the
magnitude of a Complex by defining this as a conversion from Complex to
float:
9.2
  // (within Complex definition)
9.2
  operator float()
9.2
  {+ im*im); }
9.2
int main()
9.2
{a(/*...*/) ;
9.2
  float f = a;
9.2
    // f takes magnitude of a
9.2
}
9.2
To convert a class to a pointer, you would have to typedef a new name
for the pointer; * is not allowed as part of the type name of a
conversion operator.
9.2
It is not advisable to use this sort of type conversion unless it is
specifically useful. Such a case would be some sort of container class
whose main purpose is to hold an object of another type. uá
9.2
Rather an abrupt ending, I fear, but the complete article is nearly 10
pages long. So, for the next exciting episode, youæll have to wait until
next month. Sorry! (If youære really desperate, look on the monthly
program disc!) Ed.
9.2
PD Column
9.2
David Holden
9.2
Regular readers will know that, unlike those with similar titles
elsewhere, this column has never consisted of lists of the latest PD
programs. I prefer to write about the subject in more general terms, and
only dwell on specific programs where I think they are either
exceptional or of universal interest. I would rather try to interest
readers in the idea of PD and Shareware in the hope that they will take
the trouble to spend a few pounds on the catalogues of the main
libraries and discover for themselves just how much isáavailable.
9.2
My main aim in this column is to point out to Archive readers, who tend
to be the more mature and sensible Acorn users, that it isnæt all
desktop Ésilliesæ and shoot-æem-up games, but that there are some
exceedingly useful applications. I have had a few letters recently
suggesting that I should mention one of the most popular Shareware
programs, because although Iáhave featured it before (it was a winner in
a previous APDL competition), there are now many new readers who may not
have heard of it.
9.2
One of the main problems with commercial programs is that they tend to
have all sorts of wonderful new features included which are designed to
make good advertising copy and give the magazines something to write
about. In fact, 99% of users have no need of these features, and they
simply increase the size and complexity of the program and help to
inflate the price. This Égalloping featurismæ is well known with PC
programs, and has reached such a stage that many popular programs have
now spawned so-called Éliteæ versions from which many of the more
esoteric functions have been stripped.
9.2
Shareware programs are written for markets where the user will purchase
on the strength of what he sees the program do rather than on the
advertisements, so these programs rarely suffer from this disease. There
is one area in particular where this problem seems to get out of hand,
and that is databases. Most commercial programs try to do everything
and, as a result, become highly complex and eat up megabytes of memory
and hard disc space. It is now very rare to find a commercial database
that can be run from floppy disc. The fact is that most people donæt
want all these wonderful features, but just need an easy-to-use system
to keep names and addresses, business contacts, client records, or info
about their hobby.
9.2
Powerbase
9.2
Powerbase is a flat file database which will probably do everything that
all but a small minority of users will require. It falls nicely between
the very simple text-only address book type and the highly complex
relational database. It is very easy to set up and use a straightforward
database. For example, you could create a name and address database in a
few minutes, yet Powerbase also has many features found in more complex
programs.
9.2
It has good search and interrogation features and printing is well
supported. As well as providing for mail merging with Impression and
Ovation, it can also print address labels and reports. Once again, this
is very simple to do, normally just by Époint and clickæ, without the
need to spend hours pouring over the manual. In particular, it is easy
to Éfilteræ a record so that only certain fields are displayed on screen
or printed.
9.2
As you would expect, Powerbase can import and export CSV files, which
makes transferring to and from other databases simple. Most functions
can also be invoked by a keypress, which makes entering data much easier
as you donæt have to switch repeatedly between mouse and keyboard. Most
fields can even have a pop-up menu from which you can select data, so if
a field has only a few options, you can select the required one instead
of typing it.
9.2
Although Powerbase is not relational, it does have some features which
are normally only available with relational databases. Fields can be
linked to Éexternalæ files, e.g. a large text file or graphics, and
fields can use external validation tables.
9.2
Powerbase comes with a good manual, (around 60 pages), some example
databases, and a short tutorial which will get you Éup and runningæ
very quickly. Registration is normally ú10, but owing to previous
successful offers where I have provided Archive readers with a pre-
registered version, I have arranged with the authors, Derek and Steven
Haslam, to supply a fully registered copy, complete with laser printed
manual and tutorial. The price of this will be ú14, which includes the
ú10 registration and covers the costs of printing and postage, and I
will include the Powerbase Admin Suite, which is a collection of
databases designed for keeping student records.
9.2
Easibase
9.2
This is another Shareware database, and it is even easier to use, mainly
because it is very much less complicated. It was written by David
Ramsden and has a registration fee of ú5.95.
9.2
Easibase is a straightforward flat file database. The main feature which
makes it very simple to set up new databases is that it uses a separate
ÉFormEdæ type program to create the database viewing window. You can
drag the various fields about, alter their size and colour, and set
their characteristics.
9.2
This monthæs special offer is therefore a disc with a copy of Easibase
and the unregistered version of Powerbase (without the Admin Suite) for
just ú1 (or four 1st class stamps). If you want a fully registered
version of Powerbase with printed manual plus the Admin Suite, and an
unregistered copy of Easibase, then the price will be ú14. In either
case, please specify whether you want an 800Kb or 1.6Mb disc and send
your order to the APDL address inside the back cover.áuá
9.2
Starting Basic Part 3  Ö Keywords
9.2
Ray Favre
9.2
The computer needs to be able to translate the Basic program
instructions into corresponding internal actions to carry them out. To
do this, there has to be no doubt about the meanings of the Éwordsæ of
the programming language and how they are put together in Ésentencesæ.
The Éwordsæ are called Ékeywordsæ and every Basic instruction
(Ésentenceæ) must have (or uniquely imply) at least one keyword Ö rather
like every sentence in English must have a verb. The whole point of
Basic is that these keywords closely match their English equivalents in
meaning, making it easier to learn (for English speakers!).
9.2
Each keyword therefore has a rigid description of how it can be used:
down to whether spaces, commas, semi-colons etc are important and even
where it must sit in a Ésentenceæ. These essential details are called
the Ésyntaxæ Ö another straight copy from English.
9.2
Enter Basic from a Task Window (see Part 1) and type HELP . (note the
full stop) for a full list of keywords Ö and typing HELP <keyword> gives
the syntax of any one of them. (Type *HELP Syntax Ö note the asterisk Ö
to get an explanation of the syntax symbols! Better still, Acornæs BBC
Basic Reference Manual must really be regarded as essential if you
intend to program frequently.) (The Basic VI manual is ú20 through
Archive. Ed.)
9.2
Most keywords have an optional abbreviated form, frequently with a full-
stop at the end e.g. P. for PRINT, and these can certainly reduce finger
wear when typing in programs. They are listed in the Basic Reference
Manual. When you LIST the program in a Task Window (or save and reload
it in Edit) the full names will be shown, so legibility is not lost by
using these abbreviations. (At least one of the non-Acorn alternatives
to Edit has an option which picks up the abbreviations as you type them
in and converts them immediately to the full keyword on the screen.)
9.2
Youæll be relieved to hear that this series will not be attempting to
explain 160 or so keywords one by one. Instead, it will introduce the
main ones as they arise under topic headings.
9.2
Readeræs suggestion
9.2
We have already stressed that all keywords are strictly in upper case
only and that we would deliberately put variables in lower case, to make
listings easy to read and to avoid conflicts with keywords. However, a
reader in Holland has suggested that it will be even easier to read if
we use variable names with initial capital letters only and do not use
the underscore character. For example, LoanAmount instead of loanamount,
and AmountPerPayment instead of amount_per_payment.
9.2
This seems a good idea, so weæll try to adopt it from now on in the
series, except in the places where it wonæt help.
9.2
He also suggested that beginners will be helped if additional spaces are
used within our listings of Basic statements e.g.
9.2
PRINT integer% * real instead of  PRINTinteger%*real
9.2
Again, I am happy to try this, although, in this case, training my
fingers to remember may not be so easy!
9.2
Back to keywords ...
9.2
We have used the two keywords REM and PRINT several times already and
weæve also included ONáERROR in the ÉLoanæ listing. It is worth saying
more about these three now.
9.2
Keyword REM
9.2
This ought to be the most often used of all keywords. It does nothing.
Everything after it on the same program line is ignored by the computer.
It is therefore used to make remarks/comments about the program, and
also to mark boundaries between segments of the program. ÉLoan_2æ gives
plenty of examples of both these uses. Get into the habit of using REMs
as you go, rather than Éleave them until lateræ.
9.2
It is also often used to temporarily Édeleteæ a line or part of a line
of a program during development, to avoid having to re-type it if it is
subsequently needed. Just type REM in front of the part to be Édeletedæ
temporarily.
9.2
We have also seen that using REM>ProgName as the first line of the
program will automatically save the program under ÉProgNameæ if we use
SAVE in Basic command mode.
9.2
Keyword PRINT
9.2
This is mostly used to write and format text strings and numbers on
screen. It actually sends characters to the currently configured Éoutput
streamæ, e.g. can also send text to a printer Ö with or without also
sending it to screen. (Modern preference is to use Édrag & dropæ or the
Wimp Message system to activate printers, rather than direct printing
from Basic, but we will, nonetheless, say a few words about it in a
later article. Other Archive columns are also currently active on this
subject.)
9.2
PRINT can be followed by several possible format modifying symbols, e.g.
comma, semi-colon, single quote, space, some of which are used in
ÉLoan_2æ. These modifiers generally alter the printed format (from the
default format) for one operation only. It is therefore important to
know the default arrangements.
9.2
Default Print arrangements
9.2
By default, numbers are printed in decimal and right justified in a
Éprint fieldæ of 10 characters wide. (Effectively, normally giving 8
invisible columns across the screen, which can be altered.) Strings are
printed left justified in the Éprint fieldæ.
9.2
The only way to get used to the defaults, symbols and the Éprint fieldæ
is to try it out and the short listing ÉPrintAidæ on the disc would be a
useful playground.
9.2
A comma tends to set/reset things to the default formats. The semi-colon
östops the text cursor from movingò Ö either starting to print a
following text/number from the current cursor position; or holding the
cursor immediately behind the last character printed instead of a
<return> effect.
9.2
PRINT TAB(), with a single number in the brackets, moves the cursor to
the right by that number of characters before starting the print
process. It does not change the L/R justification. If the text cursor is
already further to the right of the Tab value you ask for, a new line
will be started first. This instruction works with printer output also.
9.2
With two numbers in the brackets e.g. PRINT TAB(10,15)String$, the text
cursor will be forced directly to character position 10 on line 15 Ö
from the LH edge and top respectively, not forgetting that the top LH
corner is position (0,0). Printing will start from there, overwriting
anything already there. This instruction will not work with printer
output.
9.2
When using TAB it is necessary to keep an eye on the display mode Ö some
have more text lines and/or characters per line than others, which can
lead to unexpected results. The User Guide has a useful list of screen
modes (called Éold styleæ if you have a RiscáPC!)
9.2
Other features of PRINT will be covered as and when we come to them.
9.2
Keyword ERROR
9.2
If the computer detects something wrong whilst it is churning away it
will usually try to let you know by displaying an Éerror messageæ. There
are many error messages and they occur at several levels. We
deliberately induced one from the Command Line in Part 1, and (very)
occasionally you might get one generated from deep down in the internal
workings of the machine. Much more common are those generated by the
programming language or the application program currently running. In
Wimp applications in particular, it is very easy for the programmer to
incorporate custom-built error messages.
9.2
In programming, Éerroræ has a wider meaning than its normal English
usage. It includes helpful warnings that are aimed to stop you doing
things you may not want to do, e.g. close an amended file before you
have saved it. Some errors are Éfatalæ, i.e. you will not be able to
continue running the program and you might even have to restart/reset
the computer. ÉFatalæ errors will almost certainly cause you to lose any
unsaved data/typing and, by the well-known laws, will generally occur
just at that one time that you thought you would risk carrying on
without saving! (Pause here while I save some typing!)
9.2
Our main concern in these articles will be to harness the help of the
Basic error message system to overcome problems while we are developing
programs Ö and the keyword ERROR is the means provided. It is most often
met, as in our ÉLoan_2æ listing, with a second keyword ON, as in the
instruction:
9.2
ONáERROR <do something>
9.2
This dictates how the program after that point will react when it
detects something wrong. If you want a different reaction later in the
program you can introduce a different ONáERROR line which will supersede
the previous one. When an error is detected, the program will jump from
wherever it is back to the ONáERROR line last encountered and carry out
those instructions before trying to carry on. Generally speaking, while
developing a program, we want to stop the program after reading the
error message Ö so that we can correct it before trying again. Otherwise
we are likely to run into the same error again and again in and endless
loop. This is why our ÉLoan_2æ listing ends the ONáERROR line with the
keyword END, whose meaning here is self explanatory.
9.2
To gain familiarity with common error messages, introduce some
deliberate mistakes into the ÉLoan_2æ listing and then run it, e.g. miss
off one (then both) quote marks from a string declaration; assign a
string to a numeric variable; miss out a colon before a REM etc. Do you
understand the error message? As added interest, assign a real number to
an integer variable. Do you get an error message? What has happened? All
this, and more, next time!
9.2
We will take ÉLoanæ further forward next time, when we introduce
procedures and functions. Donæt forget the feedback, to: 26 West Drayton
Park Avenue, West Drayton, Middx. UB7 7QA.áuá
9.2
Puzzle Corner
9.2
Colin Singleton
9.2
I have been asked (by a former winner) whether I know the answers to my
puzzles.  Most of the time Ö Yes! Puzzle-setters, however, are only
human. It can happen, particularly if I have published a modification of
an old puzzle, that someone might find a better solution than mine.
Publishing a column like this is an excellent way of confirming (or
improving) the solutions to puzzles on my files! The solutions published
the following month are generally mine, because I send the column to
Paul before the entries come rolling in.
9.2
Now Ö the latest winners ...
9.2
(30) Rectangles
9.2
This is a modification of my earlier puzzle, and it caused a few
problems. The wording of this version required the sides of the outer
rectangle to be different from those of all the inner ones, which
invalidates the 9╫13 solution found by a number of readers. Your entries
confirm the 8╫16 solution published last month. The winner is Tony
Houghton of Southampton.
9.2
(31Ö33) Tennis Balls Ö 27 Digits Ö Loony PAYE
9.2
Several readers sent all-correct entries. I only asked for one solutions
to 27 digits Ö you could choose from 191618257269258476354938743,
181915267285296475384639743 and 191218246279458634753968357, or their
reversals. The winner is Paul Marshall of Hartwell, Northants.
9.2
... and last monthæs solutions ...
9.2
(34) Euleræs Magic
9.2
This is a variation of a puzzle in my old Competition Corner (Archive
4.8 May æ91). There is no solution of order-2 or order-6, and the
order¡10 problem baffled mathematicians for nearly two centuries before
a solution was found. There are numerous solutions for the other orders,
of which the following are examples. All these, except the order¡3 and
the order¡10, are Édiagonalæ.
9.2

9.2
(35) Multiple Factors
9.2
You can solve this by computerised brute force or by logic. If the prime
factors of a number are:
9.2
then the number has (p1+1)(p2+1)...(pn+1) factors including 1 and the
number itself. It is thus not difficult to discover that 840á=á23╖3╖5╖7
has 32 factors.
9.2
(36) Monkey Puzzle
9.2
The weight and the monkey remain on the same level relative to each
other. This is true if the monkey climbs up or down the rope, jerks it,
lets go and grabs it again Ö anything!
9.2
(37) Multiplication
9.2
2á╫á14á╫á307á=á8596. The other solution is 1á╫á26á╫á345á=á8970.
9.2
... this monthæs prize puzzle ...
9.2
(38) Where on Earth?
9.2
Now for something completely different! This puzzle was inspired by one
recently published in New Scientist, which you might still be able to
enter, if you are quick. Four points on the surface of the Earth are
such that each is equidistant, as the crow flies, from each of the
others. Can you find four towns in your atlas which fit this requirement
as nearly as possible? This is a case where a reader might well be able
to improve on my solution.
9.2
... and this monthæs prize quickies ...
9.2
(39) House Number
9.2
Fred lives in a house with a three-digit number. The sum of all the
house numbers less than Fredæs equals the sum of all those in the road
greater than Fredæs. There are no house numbers missing. What is Fredæs
number?
9.2
(40) Birthdays
9.2
A group of people are attending a party. I can deduce from their number
that there is a better than even chance that two have the same birthday.
What is the smallest number for which this is true? (Day and month only,
not the year. Ignore February 29.)
9.2
(41) Back-tracking
9.2
What is the next term in this sequence? áá61áá52áá63áá94áá46áá??
9.2
Comments and Solutions
9.2
Good Luck! Please send comments, contributions and solutions to me at 41
St Quentin Drive, Sheffield, S17 4PN. Solutions should reach me by
Friday 10tháNovember, please.áuá
9.2
Communications Column
9.2
Chris Claydon
9.2
This new column is the result of a Éconversationæ Chris and I have been
having via Arcade BBS. Whilst I donæt always agree with Chrisæ views, I
am happy that he is willing to share his ideas and expertise through
Archive. (Thanks Chris!) If you have opinions on the subjects raised in
this and subsequent articles, as always, please feel free to express
them Ö either to Chris or to me. Ed.
9.2
Donæt turn the page! Even if you currently have no interest in comms,
hopefully you will have after reading this new column for a while! Even
if you donæt believe that you have a use for a modem, I assure you that,
once you have one, you will wonder how you ever managed without it.
9.2
I will use this first column to introduce you to electronic
communication in all its forms and to explain what it means for the
individual and for society in general. Next month, I will explain how
you can get involved, what equipment you need and how you can use it.
9.2
But first, let me introduce myself. I run ARMed Forces Software and the
ARMed Forces Multimedia BBS, and I have been involved in communications
for nearly two years. I have written a complete bulletin board server
system called ÉImmediateæ which uses an intuitive RISC OS interface
rather than the usual text-based system. I regularly use Fidonet and
Internet, and youæll find me on most of the Acornrelated bulletin
boards.
9.2
Introducing comms
9.2
So what can you do with a modem? Comms is fast becoming an integral part
of our society. Here are a few examples of how useful it can be:
9.2
Ö You can work from home Ö a modem allows you to swap information easily
with your office.
9.2
Ö You can easily meet new friends with the same interests as you. There
may not be anybody else in your town interested in Acorn computers, but
there are so many people on the computer networks that you can guarantee
to find plenty of people who share your interests.
9.2
Ö You can send a letter or a file to anywhere else in the world, and
have it arrive instantly for almost no cost!
9.2
Ö You will find that if you have a problem Ö say you canæt work out how
to use program X Ö you can simply post a message describing your
problem, and within a few hours you can get replies from many different
people, all helping you out Ö and often contradicting each other!
9.2
These days, most bulletin boards carry such an enormous range of files
that you can simply search for, say, a program to draw graphs and,
within minutes, youæve found twenty, and downloaded them all to your
computer! You can then try them all and pick the best one! Your phone
costs will be much cheaper than using a PD library, and there is a much
wider range of software available than any PD library could ever hope to
supply.
9.2
There are massive amounts of sound and graphics available, you can
always find the ideal clipart for your latest DTP or multimedia work,
though you may have to hunt through a lot of similar files. If you want
a picture of a labrador, say, you might have to try a lot of pictures
called Édogæ before you find one, but you may be lucky and find one
called Élabradoræ! You might have to try several Bulletin boards to find
exactly what you want, but itæs always out there somewhere! The biggest
problem with comms at the moment is knowing where to look.
9.2
The most popular use for the international computer networks currently
is simply to socialise Ö you can chat in real time with large groups of
other people just by typing at the keyboard, or you can use conferences
in which you post a message. People who also contribute to that
conference look at your message and, if they wish, write replies. You
can see the replies the next day when you pick up your mail, and if you
wish, write your own replies in turn, or respond to someone elseæs
message. This method is much easier on the phone bill, which need not be
very big at all, providing you are sensible with the amount of time you
spend downloading large files and chatting with Australians!
9.2
How does it work?
9.2
There are several worldwide computer networks available. These can be
split into two main groups Ö Fidonet technical networks (FTN) and the
Internet and its variants.
9.2
Fidonet is a worldwide network run by computer enthusiasts for the
exchange of private and public mail and, to some extent, the exchange of
files. Because messages are passed between BBSs via the normal phone
system, once a day during the early morning, it is relatively slow. A
message will usually have to pass through several boards to reach the
destination. It will usually take from one to four days for a message to
get through, depending mainly on the physical distance it has to travel.
Times can vary a lot depending on the route the message takes. Although
Fidonet is an international network, sending messages over very long
distances isnæt recommended. One message I know of took twenty-two days
to get to Australia. This means it went through twenty-two different
peopleæs bulletin boards and each one paid to transfer it, some by
international calls.
9.2
There are many other networks which are run using the same software and
protocols as Fidonet, including a dedicated Acorn network called
ÉRiscNetæ.
9.2
In contrast, the Internet is run largely by commercial providers and
academic institutions who are linked by constant high speed data links,
allowing all data and messages to be transferred almost instantaneously
between them. You can then dial into one of these Éprovidersæ of the
Internet and transfer mail. This is similar to transferring mail with a
BBS, but more complex and slower. Of course, these companies will charge
you for the privilege Ö you can expect to pay at least ú120 per year for
an Internet account, plus phone charges. A similar alternative to the
Internet is JANET, the Joint Academic NETwork, but this is only
available to academic establishments.
9.2
The solution to this problem is Bulletin Board Services (BBSæs). These
are computers which you can dial up to transfer mail and/or files. They
are run by comms enthusiasts (System operators, known as ÉSysOpsæ),
usually free of charge, although most sysops rely on donations from
users.
9.2
Most bulletin boards provide Fidonet messaging, and many also provide
free access to the Internet Ö several Acorn boards, including my own,
will give you access to Internet mail, and your own email address for
free. It isnæt quite as quick as a direct Internet account, and you
wonæt have access to Internet file transfer and the World Wide Web, but
youæll probably not need these Ö most bulletin boards provide a very
wide range of their own files, and the WWW is not usually necessary.
9.2
Essentially, WWW is a text display system with some basic graphics
abilities. There is a massive amount of information available, but what
the media hype doesnæt tell you is that there is no way to find what you
want unless you know where to look. So as an ÉInformation Superhighwayæ,
it lacks a lot Ö you canæt simply look up the information you need. WWW
has succeeded in making one part of the Internet easier to use, but it
is still not something for novices, unlike a BBS where there is a
friendly sysop to help you out if you get stuck.
9.2
If you are new to comms, the first thing to do is to call up a good
bulletin board which supports your interests and create a user account
there. Once you have an account, you can join and leave message
conferences from Fidonet (Echoes) and conferences from Internet (Usenet
Newsgroups) and start to chat with other people. You can send Internet
email and Fidonet netmail to other individuals and you can download
files from the hard disc of the BBS.
9.2
For the benefit of all the users, most BBSs have a limit to the number
of files you can download to your computer. In order to get more
downloads, you have to send some files to the BBS, so there is always a
flow of new files of all types appearing on BBSs.
9.2
If you are a newcomer to comms, please remember that the Internet isnæt
all that the media make it out to be, though it is very useful. If you
use a BBS, you can try comms out free of charge with no long term
commitment, maybe getting an Internet account later if you decide that
you want one.
9.2
I will include an ongoing feature in this column listing good Acorn
BBSs. If you have a BBS which you would like me to include, drop me a
line and Iæll put it in, maybe review it as well!
9.2
Next month, I will discuss what software and hardware you need to get
online and how to use it.
9.2
If you have any feedback on how you would like me to develop this
column, or suggestions for topics to cover, you can contact by any of
the following ways:
9.2
Voice phone: [phone].
9.2
ARMed Forces BBS: 01962-880003.
9.2
Web: http://www.icafe.co.za/mirage/ARMedForces.
9.2
Internet email: [e-mail] or [e-mail].
9.2
FidoNet Netmail: 2:252/501.
9.2
RiscNet Netmail: 7:44/212.
9.2
Post: Chris Claydon, 38 Main Road, Littleton, Winchester, Hampshire,
SO22 6QQ.áuá
9.2
Donæt forget the Archive Internet Glossary (perhaps I should have called
it a Comms Glossary!) which will help you as you seek to enter this
jargon-filled world! Ed.
9.2
BBS Name:  Location:  Phone Numbers:
9.2
Arcade  London  01816-542212 (4álines)  01816-554412 (1 line)
9.2
The Digital Databank  Welwyn Garden City  01707-323531 (3 lines)  01707-
329306 (1 line)
9.2
The Plasma Sphere  Lymm, Cheshire  01925-757920 (1 line)  01925¡757921
(1 line)
9.2
Arctic  London  01819-031308 (1 line)  01819-031309 (1 line)
9.2
Rich In Paradise  London  01716-240740 (1 line)
9.2
Galaxy  Eccles (Manchester)  01617-079306 (1 line)
9.2
Software Copy Protection
9.2
David Holden
9.2
I was motivated to write this by correspondence and conversations
arising from comments in the PD Column in issues 8.10 and 8.11 and
recent complaints about hardware keys. I must point out that these
opinions are entirely (but certainly not exclusively) my own, so if you
disagree, please write to me at the APDL address and not to Archive.
9.2
In those articles, I dealt with the attitudes a shareware author needs
to adopt towards people who use his programs Ö those who register, and
the less scrupulous, who do not. I pointed out the pitfalls awaiting an
author who is more concerned with preventing unauthorised use than
providing an attractive product for the honest user. I drew comparisons
between the attitude required, and that displayed by some companies
producing software for Éconventionalæ distribution.
9.2
As users of Acorn computers, we are plagued (and I use the word
deliberately) by protected software. Letters in Archive show that
protection methods used by some companies cause great difficulties to
their customers Ö yet they, and others, persist. This is the dilemma
that I shall try to address.
9.2
Why piracy exists
9.2
Computer software costs only a fraction of its retail price to
manufacture but is heavily Éfront end loadedæ. In this, it has much in
common with the record industry, where forging is also rife. The package
may cost only a pound or two to produce, yet be priced at many tens or
even hundreds.
9.2
This is not profiteering because it costs a lot to develop and market a
program. This has to be paid before a single item is actually sold.
Often, thousands of copies must be sold before the investment has been
recouped and the program begins to show a profit. Then there will be
improvements, bugs to fix, extra features to add, so a lot of the
Éprofitsæ will need to go towards further development.
9.2
The pirate, because he has no development or promotional overhead, can
make huge profits. If he produces an exact copy and sells it at less
than half the price, his net profit is the selling price less the
(small) manufacturing cost. Software protection can do nothing to stop
this because the pirates just duplicate the protection Ö even dongles!
It does not matter how complex the copy protection is, the forgers can
afford to spend more on bypassing it than those who devised it Ö they
have so few other costs.
9.2
Why copy protection?
9.2
The answer that is given by those who favour it, is that, if software is
not protected,ï people will give copies to all their friends, seriously
reducing sales. This is demonstrably nonsense! Not one among the worldæs
most popular and best selling programs is copy protected!
9.2
The statistical logic is irrefutable. Unless the most successful
companies are mistaken, and their success seems to indicate that they
arenæt, software protection reduces sales.
9.2
The exceptions
9.2
There are areas where copy protection may be advisable, and one is
games. I assume, for the sake of this argument, that games purchasers
are likely to be younger users. I do not imply that they are less honest
than older users, just that the desire to have the latest games is
likely to be intense. They (or their parents) may not have the
wherewithal to buy them all, so there will be a great temptation to
Éswapæ with friends. Most games have little documentation, so having the
software without it may be no problem. I am inclined to sympathise with
games publishers, but any protection should be as simple as possible.
They cannot stop copying, so all they can do is make it less easy for
the inexperienced.
9.2
Education is another area where protection could be justified. Programs
used in education may be installed on a large number of computers, and
copies may Éescapeæ and appear on students own machines.
9.2
Protection methods
9.2
The most important fact about copy protection is that nothing works.
Even the most complex systems only stop copying by the non-expert. This
is the majority of users, so arguments in favour appear attractive, but
what is overlooked is that a lot of dishonest users are experts. The
market in counterfeit games exists largely because of copy protection.
Kids do not have the money to buy all the latest games, so when they see
pirated copies on sale cheaply at a car boot sale or street market they
are not fussy about their origins. So this money goes to the pirates and
not a penny to the companies that originally produced the products.
Anything which stops this diversion of funds must be good for the
industry, but copy protection is not the answer. In fact, it is part of
the problem.
9.2
Protection methods often involve tampering with the structure of the
disc, so certain parts cannot be read by conventional means. The program
checks to see if the disc conforms to the original specification and, if
not, it assumes it is a copy, so the program can only be run from the
original floppy. The Ékey discæ system uses a similar strategy, but
enables the program to be copied to another disc, e.g. a hard drive, and
requires the original to be inserted when the program is started. These
methods are inconvenient to a user and no barrier to a dishonest expert.
They require the user to have the original disc to hand and waste time
inserting it, and if anything happens to it, the program is useless
until a replacement is obtained.
9.2
Another method is a Éhardware keyæ. A few years ago, these appeared on
PCs in great profusion as the hated printer port Édongleæ. Within a
short time, they vanished. The reason was simple; the system is only
feasible if it is used by a small number of people. If you have half a
dozen programs using dongles, it is likely that they will interact in
some way, and even if they donæt prevent the computer operating
properly, they may cause printing problems, and the physical
difficulties of having all that junk hanging out of the back are
obvious. An alternative, using a circuit board plugged onto an expansion
slot, was even more ridiculous, as a PC has only a finite number of
slots, so as soon as more than a very small number of companies used
them, they became impracticable.
9.2
PC copy protection vanished, not because of the sudden enlightenment of
the software producers, but because people buying software had had
enough Ö they just refused to purchase copy-protected programs!
Companies that persisted saw sales plummet.
9.2
Both of these methods do still exist on very expensive specialist
software that is run on a dedicated machine, but they have disappeared
from Émainstreamæ PC packages.
9.2
Comparison with the record industry
9.2
A lot of money has been spent trying to develop copy protection for
audio CD. The introduction of Digital Audio Tape (DAT) was delayed,
owing to fears that people with a DAT recorder would be able to tape
friendsæ CDs without loss of quality. For years, the record industry has
tried to get governments to impose a surcharge on the price of cassette
tapes on the grounds that these are used to copy records, thus
diminishing record sales.
9.2
Many people tape their own records so that they can listen to them in
their car. Strictly, this is actually a breach of copyright, and the
record companies say you should purchase a cassette in addition to the
record or CD. However, people do not have unlimited funds and so, if
they were obliged to purchase both tape and disc, they would probably
spend less overall on recorded music, because it would be such poor
value for money.
9.2
Although most people might feel morally justified in making a Épersonalæ
copy of a record, making a copy for a friend is altogether different.
This is the equivalent of Software Piracy. But is this always
disadvantageous to those who sell the product? Often, an introduction to
a new artist comes from Éborrowingæ a tape from a friend. Similarly, if
you use a program you think is wonderful, you want to share it. With
Shareware this is exactly what you are encouraged to do, but not with
conventionally distributed packages. Why? Surely, even the most
hidebound marketing manager can see that the best promotion for a
software product is to have it Ésoldæ by an enthusiastic user.
9.2
Technically, this is software piracy, but when done between friends for
the promotion of a product, it can be beneficial to sales. I do not
suggest that it should be encouraged, but it will happen. The recipient
may like it, in which case he will, if he is honest, purchase it, and
everyone gains. What if he is dishonest? Well, as I have explained in my
previous articles, only a complete fool devises a marketing strategy
based on the assumption that all prospective customers are thieves. In
any event, the new user will probably want the proper manuals and to be
able to get upgrades and help when required, so there is (or should be)
a lot of incentive to purchase the program.
9.2
These incentives are much less with games, so if there is no copy
protection, the company must rely on honesty. However, this does not
diminish the advantage of Élendingæ between friends. To recall my
analogy with music, there is only a finite amount of money available to
purchase software. Even if the recipient is not honest and continues to
use a copy, he/she may like the game so much that they do buy others
from the same stable.
9.2
The arguments for
9.2
So far I have tried to give good, practical reasons why I believe that
software protection is not only of no benefit to sales, but may actually
reduce them. There are very few arguments in favour, but the one which
is almost invariably accepted as an Éobviousæ truth is that, if software
is not copy protected then, because people can make copies, they will
make copies. The problem countering this is that, although I am certain
that the premise is false, it is very difficult to disprove. I am forced
to resort to the argument I gave at the start Ö that none of the best-
selling programs are protected. The two which have sold by far the most
in the history of computing, and which have gained almost universal
usage, are DOS (in various guises) and Microsoft Windows, neither of
which use copy protection. I do not doubt there are many Éborrowedæ
copies of both in use, but Microsoft wisely decided that the advantage
of no copy protection far outweighs this. Whatever you may think of Bill
Gates, you can hardly say that his company is financially disadvantaged
by its policy on copy protection!
9.2
The fact is that this whole argument is based on a false assumption;
that someone using a pirated copy of a program is depriving the company
of a sale. The company says that if the product costs ú100 they have
Élostæ this money to piracy. Isnæt this Éobviouslyæ so? This is just not
true. People who use pirated software wouldnæt buy the original. If the
software is copy protected, and the protection is too much trouble to
bypass, these people wonæt buy it, they will just use something else.
That means their user base (i.e. their advertising base) is one less and
their rivalæs user base is one more!
9.2
(Some years ago, when their high prices were challenged, one company
said that they felt justified in charging three times the Érealæ price
because they believed that for every item sold, two illegitimate copies
were made! Not surprisingly, some companies who had purchased a copy
then felt justified in installing it on at least three machines.)
9.2
Copy protection does not prevent software piracy, quite the reverse. The
more intricate the protection, the less likely it will be bypassed by
Éamateursæ, leaving the field open for the professional forger. This is
the type of piracy that does hurt. Unlike kids swapping games, it takes
money out of the industry, money which cannot then be spent on
legitimate purchases. Certain far-eastern countries are renowned for the
huge number of forged CDs and computer packages they export, often to
people who believe they are getting the real thing at a discount.
9.2
The real reason
9.2
It would be nice if I could find some reasonable argument in favour of
software protection. The truth is that the reasons for using it are
psychological rather than real Ö they have their roots in paranoia, not
logic.
9.2
Those who advocate copy protection do so from a genuine fear that, if
they donæt employ it, Éeveryoneæ will use a pirated copy of their
program and sales will fall. As I have pointed out, effective copy
protection is a myth Ö it should more properly be called copy
discouragement Ö so, whatever efforts they make to prevent copying, they
will not stop someone who is determined.
9.2
There would be no harm if it were not that copy protection always
inconveniences the legitimate user, which is why it has all but vanished
from PCs. Here, there is so much software available that people do not
need to buy something which they find bothersome to use, so companies
that could not accept this, saw their sales reduced. Unfortunately, this
is not the case with Acorn machines. There are just not enough companies
to enable Émarket forcesæ to work properly.
9.2
It seems that nothing will shake the conviction held by some companies
that copy protection is necessary. They want to use it, they have always
used it, and so they find some means of justifying it. They would prefer
that their customers be inconvenienced and dissatisfied, and therefore
sales diminish, rather than allow a small percentage of dishonest people
to use a pirated copy. No amount of logical argument can counter this
attitude.
9.2
The final argument
9.2
In many years of dealing with people, I have found that those who are
most trusting also tend to be the most trustworthy. Honest people expect
others to be honest. I resent the assumption that I am a potential thief
who must be prevented by physical means from distributing copies of a
program. We all know that a certain amount of pilfering takes place from
supermarkets, but would you feel happy shopping in a place where they
insisted on searching you before you left because you might be a
shoplifter? Few people would put up with this and would go elsewhere,
yet we are expected to tolerate equivalent conduct from people who sell
software instead of groceries.
9.2
All the evidence I have, both personal and anecdotal, is that companies
that do not use protection, and who have faith in their customers, seem
to be the most friendly and helpful when those customers have problems.
Once again, I suspect this is a psychological effect. Companies that
trust their clients and feel happy with them will proclaim this attitude
in their dealings with them. It will become the Énaturalæ way that all
their staff interact with customers. If this trust is not felt by those
at the top of the company, their attitude will be sensed by employees
who deal directly with customers. No matter how much money is spent on
Écustomer relationsæ, if they see them as potential pirates, this must
inevitably be reflected in the companyæs interaction with them.
9.2
I suspect that this article could generate a certain amount of
correspondence. If you do have anything to say on the subject, please do
write to me personally at APDL. If you feel you have something to
contribute, please put your arguments on disc, if possible, so that I
can perhaps produce a Éfollow upæ with some of your views.áuá
9.2
Small Ads
9.2
(Small ads for Acorn 32-bit computers and related products are free for
subscribers but we reserve the right to publish all, part or none of the
material you send, as we think fit. i.e. some people donæt know what
Ésmallæ means and there are certain things, as you can imagine, that we
would not be prepared to advertise as a matter of principle. Sending
small ads (especially long ones!) on disc is helpful but not essential.
Ed)
9.2
A305, 40Mb ICS IDE HD, 4Mb RAM, RISC OS 3, ARM 3, Acorn multisync, VIDC
enhancer, Citizen 9-pin dot matrix printer, all boxed with manuals ú600
o.n.o. Phone [phone] after 5pm.
9.2
A310, 4Mb RAM, 20Mb HD, RISC OS 3.1, Taxan 770 14ö monitor ú250 o.n.o.
Phone 01962¡733327.
9.2
A310, 4Mb RAM, 85Mb HD, 4-slot backplane, PC emulator plus other
software ú300 o.n.o. Phone [phone].
9.2
A310, ARM 3, 4Mb RAM, 40Mb HD, fitted with Acorn Midi interface (in,
thru, + 2 out) and EMR 8-bit sampler. EMR Soundsynth sample editing,
Studio 24 + v2g 24 track sequencing software, Phillips colour monitor
and newly purchased A5000 keyboard ú350. Phone [phone] after 5pm.
9.2
A410/1, 4Mb RAM, RISC OS 3.1, NewLook, NewerLook, fast 191Mb Maxtor
external SCSI HD with case, Oak SCSI interface, AKF12 monitor with CRT-
filter, KX-P1081 printer, dual PowerPad joypads with software, Populous,
Magic Pockets, Gods, Superior Golf, Saloon Cars Deluxe, PC emulator, and
lots of PD, ú550 o.n.o. Phone [phone].
9.2
A410/1, 4Mb RAM, RISC OS 3.1, ARM3, original HD replaced with 200Mb
Connor SCSI, plus extra external 200Mb Connor SCSI HD, (runs from
Archimedes PSU), Oak SCSI card, Aleph One 486 PC card (4Mb) v.22, VIDC
enhancer, Taxan 770+ multi-scan, CJE Micro 5╝ö disc controller, unused
mouse, manuals, some software, ú800. Available now in UK. Please phone/
fax Ian on [phone] after 8pm (UK) and just leave your name, phone
number, and times available, and Iæll call you back.
9.2
A3000, 2Mb RAM, Mitac monochrome multisync, Epson RX80 FT+ dot-matrix
printer, ú175 + carriage. Phone [phone] eves.
9.2
A3000, 4Mb RAM, 40Mb IDE HD, RISC OS 3.1, Acorn 14ö monitor with plinth,
ú400. Panasonic KX-P1124 dot-matrix 24-pin printer with sheet feeder,
ú200, o.n.o. Phone [phone] eves. 6¡9pm.
9.2
A3000, ARM 3, 4Mb RAM, 105Mb SCSI HD, stereo colour monitor, desk
plinth, HCCS video digitiser (never used), Epson 24-pin printer (one pin
sticking), PipeDream 4, PC Emulator 1.8 ú400 o.n.o. Phone [phone]
or email [e-mail].
9.2
A5000, 4Mb RAM, 80Mb HD, RISC OS 3.1, CC Colour Card, fan quietener,
AKF18 multisync, LC software ú700 o.n.o. Eesox Silver CD-ROM (SCSI 2)
ú120, ArtWorks ClipArt1 CD ú5. Phone Brian on 01453-832897.
9.2
A5000, 4Mb RAM, 120Mb HD, RISC OS 3.1, Acorn monitor, floating point
accelerator, Learning Curve software, ú675. Faxpack, ú95. Phone Paul on
01234-381630.
9.2
A5000, 8Mb RAM, 120Mb HD, internal IDE 105Mb SyQuest (no cartridge),
Eizo F550i 17ö multisync. Can be seen at N.C.S. ú950 complete or ú400
for monitor alone. Phone Iain on 01463-751251.
9.2
A5000, 25MHz ARM3, 40Mb IDE HD, RISC OS 3.1, 8Mb RAM, 105Mb internal
SCSI SyQuest, 200Mb SCSI HD, Oak SCSI podule, Eizo F550 17ö monitor,
ColourCard Gold, various software ú1000. HP DJ500 printer ú100. Amstrad
FX9600 Fax m/c ú100. Z88 plus accessories ú100 o.n.o. offer. Phone Dave
Kennard on 0181-368-1703.
9.2
A5000, 33MHz ARM3, 160Mb IDE HD, 4Mb RAM, less than 2 years old ú675,
14ö Microvitec 1440 0.28mm dot pitch ú200, 4-8Mb RAM upgrade ú150,
Cumana Bravo CD-ROM drive (parallel port) ú100, joystick and VTI
parallel port adaptor, Games and other software. Phone Richard on 01952-
460460.
9.2
A4 portable, 4Mb RAM, 60Mb HD, RISC OS 3.1, brand new battery pack,
BJ200 printer and AKF18 monitor with cables ú1250. Will not split. Phone
01457-852381.
9.2
A4 portable, 4Mb RAM, 60Mb HD, RISC OS 3.1, v.g.c. 22 months old,
original boxes, spare battery, ú575. Phone Mr. Gleeson on 01782-771914.
9.2
Acorn 16-bit SCSI card, upgraded for the Risc PC, complete with SCSI/CD-
ROM utilities disc, all manuals and registration card, ú70 o.n.o. CC
ScanLight 256, upgraded for the Risc PC, ú75 o.n.o. ú140 for both o.n.o.
Prices include carriage. Phone Keith on 0860-919216.
9.2
Arvis Video Graphics System, includes 16-bit framestore with real time
video digitising, Genlock, chromakey facility, mixing and overlaying any
combination of Archimedes graphics, framestore and live video, S-VHS and
composite video input and output. Cost when new ú1299 sell for ú449
o.n.o. Phone [phone].
9.2
Citizen Swift 24 colour dot-matrix printer, boxed as new with spare
ribbon and paper ú80, CDFS drivers for NEC CD-ROM drives ú7, Archimedes
Assembly Language (book) ú7, DeskEdit 2 ú5. Phone Chris on 01247-466686
after 6pm (or email [e-mail]).
9.2
Colour Card Gold, boxed as new unregistered ú150. Morley internal dual
speed CD-ROM drive ú150 o.n.o. Phone [phone] eves.
9.2
Colour Card Gold ú110, 20ö Sony monitor ú700, HP500 printer ú110, HP550C
colour printer ú200, CC HawkV9 MkII video digitiser ú90, Irlam Replay
DIY board ú140, 14ò Opus multisync for Risc PC ú180. All v.g.c. Phone
Russell on 0131-658-1225 after 6.
9.2
Cycloids, v.g.c. ú12.50. A3000 user port ú10. Archive magazines volumes
4-7 ú20. Phone Benjamin on 01449-673443.
9.2
Fireworkz Pro, boxed with full documentation, ú90. Phone [phone].
9.2
Fontasy & DrawBender ú5 each. HP Jet/Fax cartridge ú10. 50Mb SCSI HD
unused & verified ú25. BBC Basic Reference Manual ú7, Acorn ANSI C rel.
4, Programming in Pascal Teach Yourself ú5, C: A Dabhand Guide ú5,
Beginners Guide to WIMP Programming ú7, Acorn Assembly Language ú7,
various PD discs and disc sets for 50p per HD floppy. Will accept
nearest offers. Send an s.a.e. to D. Seelig, 34 Douglas Street,
Tyldesley, Manchester, M46 9EB for info.
9.2
Hearsay comms package v2.19 ú20, Impression 2 ú20 o.n.o. EasyFont 3
boxed unused ú5. Phone [phone].
9.2
Impression v2.17 ú35. PC emulator v1.7, with MS-DOS and support discs
ú25. Acorn Software Developeræs Toolkit, never used ú15. Acorn DTP with
advanced user guide ú25, Graphic Writer + Artisan + Artisan support
disc, all three for ú15. Phone [phone] eves.
9.2
PAL encoders, Pineapple PLC/3 ú50, Rombo VGA-TV Buster ú30 (see 8.10
p.63), both mint, under half price, work with modes 12, 15, 36 etc on
all machines. Only reason for sale, upgraded to AVK/3. Phone Stuart Bell
on 01403-253915 days.
9.2
Risc PC 600, 9Mb/420Mb, AKF60 monitor, plus extra software etc, ú1200.
Phone 01493¡600966.
9.2
Risc PC 600 (ACB25), 9Mb RAM, 210Mb HD, AKF85 17ö monitor, Acorn PC486
co-processor card, 12 months old, v.g.c. extended warranty, boxed, light
home use, ú1150. Phone Mr. Gleeson on 01782-771914.
9.2
Risc PC 600, 6Mb + 2Mb VRAM, 210Mb HD, 17ö monitor, quad speed CD-ROM,
Oak SCSI card, 486 co-processor, Impression and Artworks, ú1200. Phone
01202-740710 eves.
9.2
ScanLight 256, with standard sized podule ú100. Morley 16-bit SCSI
podule, still under warranty ú100. (200Mb HD and cable available if
required.) SyQuest 44Mb SCSI removable with two cartridges and cable
ú125. 4Mb SIMM for Risc PC ú90. HCCS Ultimate CD-ROM podule with CDFS
and external case / power supply, (requires Mitsumi FX001D CD-ROM drive
to be fully functional on Acorn machines) offers? My World 2+2 ú30,
QDBug ú30, Schema 1, PipeDream 3, offers? Phone [phone] or 0860-
261560.
9.2
Star SJ48 BubbleJet printer plus sheet feeder and 5 ink refills (alone
worth over ú80). Still plenty of mileage in it ú150 plus ú5 p&p if not
collected. Phone John on 01328-864177.
9.2
Various hard drives from 80Mb to 400Mb 5╝ö / 3╜ò all ╜ height, SCSI and
in good cond. with no known defects, 5╝ö SCSI 20Mb magneto-optical drive
with 5 discs, Beebug 5╝ disc drive interface and buffer, 1Mb Accodata
serial printer buffer. A5000 LC with 4Mb RAM, A5000 2nd floppy disc
drive, 40Mb IDE HD, 130Mb IDE HD. Phone [phone].
9.2
Wanted Ö Cheap non-multisync monitor for A310. Phone Brian on 01453-
832897.
9.2
Wanted Ö Colour monitor suitable for an A3000 or might buy an A3000
complete with monitor attached. Collection can be arranged. Please fax
or phone [phone] or write to Murray-Smith, Apartado 104, M123
Vale da Telha, P-8670 Aljezur, Portugal.
9.2
Wanted Ö IDE interface for A3010 or broken IDE hardcard, i.e. broken HD,
working interface. Phone Chris on 01247-466686 after 6pm (or email
[e-mail]).
9.2
Wanted Ö Risc Basic or ABC Basic Compiler. Phone [phone] or 0860-
261560.áuá
9.2
Producing an Atlas on an Acorn
9.2
Daniel Dorling
9.2
A önew social atlas of Britainò has just been published by John Wiley
and Sons. Unlike most atlases, it has been produced by one person,
myself (with a lot of help and advice). An atlas can only really be
produced by one person if a computer is used to do most of the work.
What may interest readers of this magazine is the computer which was
used.
9.2
When you tell a publisher that the kind of book you are thinking of
writing could not be created using an öindustry standard machineò, but
that you are planning to use an Archimedes computer (i.e., to them, a
Éschoolæ computer), they suspect there is something seriously wrong with
you. However, once they hear that it will contain numerous maps covering
over one hundred topics and that each map will contain greater detail
than has been published before, they tend to give you a chance. When the
atlas is delivered as PostScript files on Apple Mac formatted SyQuest
discs, they ask how it was done.
9.2
Map creation
9.2
The maps look like the hardest part of an atlas to create. In fact, for
me, writing the text to accompany them was more difficult. Most maps in
modern atlases are still drawn by hand, even if that hand is guiding a
mouse across a screen. However, increasingly, maps are being produced
from digital datasets using ögeographical information systemsò (GIS).
These tend to be very expensive software packages running on even more
expensive workstations. There are mapping packages available for the Mac
and PCs now, but these produce a very restricted set of maps. There is
still no GIS system for the Acorn machine which will produce
sophisticated maps, but there are two things which come free and,
together, these can be used to produce high quality maps of a wide
variety of designs: the Draw package and BBC Basic.
9.2
The basic idea is very simple. Draw saves its work as a drawfile. Once
the format of a drawfile is known (given in the PRM), a Basic program
can be written to create one. Once this file is loaded into Draw, it can
be annotated, printed or exported to numerous other packages. Thus,
enormous files of statistics provided by official sources can be turned
into maps using a little programming and the software bundled free with
a Éschoolæ computer.
9.2
Equal Population Grid Squares in Britain
9.2
Each small grey Ésquareæ contains 30,000 people, and eachálargeáblack
Ésquareæ contains up to 3 million people, i.e.á100ágreyáæsquaresæ.
9.2
There are several reasons why this system was ideal for my task and why
I expect many other people prefer to use this route to creating novel
graphics. Drawfiles are extremely compact descriptions of graphics which
means that each map (often of over ten thousand places) could be saved
on a floppy disc, loaded quickly into memory and drawn very rapidly on
screen. I still have to see a öprofessionalò system that will do this
with complex maps. BBC Basic is also versatile enough to allow very
quick changes to a program to be made. If you are using your own program
to produce drawfiles, you tend to be quite willing to change the program
to get exactly what youáwant.
9.2
However, one major frustration was that, although the drawfile contained
these detailed maps, the resolution is too low to see this detail
clearly, even on a very expensive monitor. Obtaining colour prints for
checking was also a slow and expensive process, as bubblejet quality is
only good enough for rough proofs. A dye-sublimation printer easily
costs more than a top of the range Acorn system and, even then, the
quality of these printers is not good enough to guarantee what the final
colours will be. The only way to test that the colours are correct is to
get a publisher to make Chromalin proofs from PostScript files, which
takes time and money. A system for simple colour matching is badly
needed.
9.2
Creating the drawfile
9.2
So how is a map turned into a drawfile? Maps basically consist of a
series of polygons filled with different colours, some lines, a few
other symbols and some text. These are referenced as objects in a
drawfile and recorded as a series of numbers. In fact, the drawfile
format is almost ideal for creating maps. Its polygons are called paths
and can contain complex features, such as multiple holes and jumps. Thus
an object such as öScotlandò which has a detailed coastline, islands off
its coast and lochs within it (which might also contain islands) can be
represented as a single path in a drawfile if the land is all to be
coloured one shade.
9.2
Before maps can be drawn, digital information about their boundaries is
required. This, it must be admitted, was extracted from a GIS. This
information is also crown copyright and so, although it is permissible
to print black and white illustrations for this öeducationalò article,
if the editor were to put the drawfiles on the monthly disc, he might
get in trouble with Ordnance Survey (who monitor the copyright). Once a
subroutine has been written which can output a drawfile path for one
place (such as Scotland), altering the program to draw a map of over ten
thousand places, is simple.
9.2
Two projections were used in the Social Atlas: a conventional equal area
land map and a cartogram in which the size of every place was made
proportional to its population. This second projection is useful to map
the social geography to peopleæs lives. Once these projections were
determined, any set of statistics could be used to colour the maps (see
the illustration of unemployment levels). Titles and keys were then
added by hand in Draw.
9.2
Another advantage of using Acorn machines is the software available.
With dozens of cheap or free graphing packages, creating illustrations
is neither difficult nor time consuming. The atlas contains over 200
graphs and charts produced in a variety of styles from PipeDream,
GraphPro and Presenter GTi as well as various public domain packages.
Again, a few short Basic programs were written to draw graphs which
other packages would not produce. For instance, a small program was
needed to create colour scatterplots of several thousand observations.
9.2
Now the text
9.2
What took most time was writing the text to accompany these graphs and
maps. Each chapter of the atlas was a separate Impression document, laid
out to a template specified by the publisher. Colour separated
PostScript files of each page were then created using Computer Conceptæs
Expression-PS package and a Linotype printer driver. (The Publisher
package was not used because a key requirement of the software was that
the author should have learnt all its bugs!)
9.2
Final output
9.2
The publisher used Sun workstations and Apple Macs, so the final
PostScript files were sent on Mac formatted SyQuest cartridges using the
MacFS software from Computer Concepts. The final product required 200Mb
of PostScript to be transferred to the printers contained in 420 files.
Only one of these files failed to print first time, and this was because
the imagesetter could not cope with its complexity and so it had to be
simplified. The limits of printing from an Archimedes computer are often
beyond the limits of the printer or of other manufactureræs hardware and
software!
9.2
 One final advantage of using the Acorn range should be mentioned. The
atlas began on an A410, migrated to an A5000 and finished up on a
RiscáPC. It grew from a floppy-based project to eventually end up on one
270Mb SyQuest cartridge. In the process, numerous printers, other
storage devices and various new releases of software were incorporated.
As with all computer systems, some of these bits and pieces broke.
Unlike many other computer suppliers, Norwich Computer Services fixed
these pieces quickly (and cheaply) Ö thanks!
9.2
öA New Social Atlas of Britainò is published by John Wiley and Sons,
Baffins Lane, Chichester, West Sussex, PO19 1UD (0800-243407); price ú35
hardback.áuá
9.2
ProArtisan 24
9.2
Malcolm Banthorpe
9.2
Why 24 bits?
9.2
One of the major advantages of the Risc PC over its predecessors, and
consequently one of the main reasons for buying it, is its support for
24-bit graphics. No longer do Acorn users have to look on in envy as PC
and Macintosh users enjoy photo-realistic graphics, albeit at some cost
both financially and, arguably, of having to put up with less than ideal
operating environments. Although the PC486 card will now allow access to
major PC graphics packages such as Photoshop and Corel Draw, I suspect
that most Acorn users will prefer to stick with native software Ö not
the least of the reasons being that the PC486 software does not yet
support a 24-bit display.
9.2
What the eye can see...
9.2
The human eye is capable, under optimum conditions, of distinguishing
about seven million different colours. Colour monitors can display only
a much smaller range, which varies according to ambient lighting
conditions, and colour prints are even more restricted. Nevertheless,
the ability to manipulate the full range of colours is still desirable,
in order to retain the maximum amount of visual information.
9.2
In order to store seven million colours, 23 bits would be required for
each pixel. The nearest whole number of bytes per pixel would be three,
and processing is simplified by allocating a whole number of bytes to
each pixel. Therefore, 24 bits per pixel has become the standard for
maximum colour resolution, giving a theoretical 16.7 million colours.
The 24 bits are composed of eight bits each of red, blue and green
information Ö 256 levels of each.
9.2
Whilst this gives, theoretically, more colours than we can ever hope to
see on a screen or on paper, it helps to compensate for the fact that
the eyeæs response to each of the primary colours is far from linear and
no cathode ray tube phosphors or printing inks can match the response of
the eyeæs colour receptors.
9.2
8 bits to spare?
9.2
Acornæs full colour sprites are actually stored as 32 bits. In this
case, the extra eight bits can be used to carry additional information,
such as the transparency of each pixel, which could determine how the
graphic will behave when combined with other graphics. In other words,
the sprite can have a variable density mask.
9.2
Although many Risc PC users will already be aware of the fact, itæs
perhaps worth mentioning at this point that even the humble Paint
application can now handle 32 (and 16) bit sprites, but only in a öthis
is not an officially supported feature, so youære on your own if you use
it and it all goes wrongò sort of way. In practice, there doesnæt seem
to be any problem with it other than that it wonæt support sprite masks
at these colour resolutions. The Paint application, as supplied, doesnæt
have the feature enabled. In order to use it, type, from the command
line:
9.2
set paint$options x
9.2
or you can add it to your desktop boot file.
9.2
A bit of history
9.2
As might be expected, some of the most significant pieces of new
software written to exploit the Risc PC have been graphically
orientated. For years, we just had to make do with only 256 colours on
the screen at any one time. The range could be artificially increased by
dithering (way back, in Archive 1.4 Ö January 1988 Ö I described a Basic
procedure which would allow mode 15 to display 2401 different dithered
colours). True to the saying, öThere ainæt no such thing as a free
lunchò, the extra colours were gained at a price Ö increased colour
resolution at the expense of spatial resolution. Going back even
further, I can remember struggling to get the most out of a four-colour
mode on a BBC model B.
9.2
In the past, the limits of colour and spatial resolution combined to
give computer graphics, even in the absence of any additional software
effects, a certain character of their own. Now that we can work with
near photographic quality, there is little or no inherent character,
other than that which we choose to add to the pictures.
9.2
Even further back, about fifteen years ago, computer graphics were
starting to become trendy, but were still prohibitively expensive for
some uses. Their limitations were often mimicked in advertising graphics
produced by more conventional means. Glowing green wire-frame images
with jagged lines, which had been painstakingly painted on paper, were
then common-place and even now appear from time to time.
9.2
Ironically, now that these limitations have vanished, computer graphics,
having lost any character of its own, often seeks to acquire the look of
more conventional artwork. Photographic artifacts such as grain and lens
flair are two of a number of effects that you may sometimes spot. It is
therefore probably significant that many graphics packages offer a wide
range of traditional painting styles which seek to emulate the effects
of pencil, brush, paint and paper. Certainly, similar effects were
attempted, to some extent, in 8-bit packages but for anything other than
simple image processing, they are probably more important now and can be
used to greater effect. One of the strengths of computer graphics is
that, although having no recognisable character of its own, it can
assume the look (whether this is desirable or not) of any other existing
medium or Ö theoretically at least Ö of any medium that you can imagine.
9.2
What can you do with 24 bits?
9.2
24-bits allow a considerable amount of processing to be carried out on a
picture, while the loss in information, as compared to the original, is
kept to a minimum. A 24-bit image generally contains more information
than immediately meets the eye. I have sometimes been surprised at just
how much detail, which is initially either invisible or only just
perceptible, can be pulled out of the shadows in an under-exposed
PhotoCD picture. Having spent some time in the distant past processing
and enlarging black and white photographs in a makeshift Édarkroomæ, I
find that I can now attempt greater image enhancements with generally
more satisfactory results on PhotoCD images without any of the chemical
mess and without temporarily putting the kitchen or bathroom out of use.
An indifferent photograph can sometimes be brought to life merely by
suppressing unwanted detail, either by darkening it or with the aid of
some selective de-focussing. Even digitised frames from a camcorder can
be much improved to produce acceptable stills with a little effort.
9.2
What 24-bit packages are available?
9.2
ProArtisan 24 is one of several 24-bit Art and Painting packages
designed specifically for the Acorn Risc PC range. Most offer facilities
both for processing existing images, such as PhotoCD, and for creating
artwork from scratch. They vary in the degrees of emphasis apportioned
to the two areas and each has its own unique features. The problem
facing prospective purchasers is to decide which one to buy.
Fortunately, several of the main packages (including ProArtisan 24) are
available as demo versions, with saving and printing disabled, either
free or at a nominal cost. Other than that, you may find a dealer who
can give you a demonstration or Ö if you can wait Ö there are always
exhibitions.
9.2
If youære not sure which facilities youære going to use most, thereæs
something to be said for supporting a software house which has
previously met your needs. In this respect, users of Claresæ earlier
Artisan programs are unlikely to be disappointed. Previous Artisan 2
users will find the user interface very familiar. Others should have
little difficulty in using it since, as I have found with other Claresæ
software that I have looked at, a lot of thought has been applied
towards making the program easy to use.
9.2
Documentation
9.2
The printed manual is similarly well thought out. After a brief
introductory chapter explaining how to install the software, it goes on
to give eight step-by-step tutorials. This is likely to be very welcome
to the many who, like me, are tempted to dive straight in, generally
ignoring any pleas to read all the instructions carefully. As long as
you are reasonably familiar with RISC OS, you will have no difficulty in
producing a series of images which give a useful foretaste of what can
be achieved with the package. As a side benefit, familiarity with the
user interface is gained quite painlessly.
9.2
Minimum requirements
9.2
To run ProArtisan 24, you need a minimum of 4Mb of RAM and 1Mb of VRAM,
and 8Mb of RAM and 2Mb of VRAM are desirable. The 2Mb of VRAM will allow
a screen resolution of 800╫600 in 16ámillion colours, and the 8Mb of RAM
will happily support an 800╫600 image. You may, on occasions, also need
to allow for sprites loaded into the sprite bank. The image is always
processed internally using the full 24-bits, regardless of screen mode,
and a backup file is also kept in memory for undo purposes.
9.2
It is possible to use a higher resolution screen, such as 1024╫768 in a
32 thousand colour mode without the display showing too much
degradation. However, working with a 256 colour screen mode will usually
be out of the question, as ProArtisan 24 does not support on-screen
dithering and so will not give an acceptable colour representation of
the image being worked on. A 256 colour mode can be of use, however, if
you are dealing with a monochrome image Ö by setting the palette to 256
grey levels.
9.2
With 16Mb of RAM you can work on a 1280╫1024 image. For anything much
larger, you will need to increase your complement of RAM chips still
further, as ProArtisan 24 does not yet support virtual memory.
9.2
Unless you are going to work on an existing image loaded from disc, the
first stage in working on a new image will be to create a blank canvas.
Its dimensions can be specified in either pixels, inches or centimetres.
There are also a number of preset size options, such as A4 and disc
label. In each case, the application indicates in advance how much RAM
will be required and how much is currently available.
9.2
The palette
9.2
Although there are 16 million colours available and the standard Acorn
colour picker can be used to select them, it is generally more
convenient to work with a palette containing a small subset. ProArtisan
24 has a number of preset palettes, each of 256 colours. The familiar
Acorn 256 colour palette is there, along with others with names such as
Éart decoæ, Éautumnæ and Éearthæ. A full 24-bit colour picker is also
provided so that you can set up your own user-defined palettes. It is
easy to set a range of smooth gradations between any two preselected
colours. It is also possible to pick up colours directly from an image Ö
particularly useful for retouching photographic images such as PhotoCD.
9.2
The paint menu
9.2
A pleasingly large number of brush types is available, many of which
will be self-explanatory, such as airbrush, watercolour, charcoal, oil,
pastel and chalk. The exact appearance of the latter three is determined
by choosing from a selection of supplied textures. The brushes work
smoothly, provided that they are not too large. One of the computer
graphics operations which I find particularly frustrating is trying to
paint with a brush that canæt keep up with the mouse pointer. I have
found that Acornæs multi-tasking can sometimes get in the way when using
ProArtisan 24 and other packages. The mere presence of some other
applications on the icon bar can make all the difference between a
smooth brush and one which lags annoyingly behind the point which you
think youære painting and may move in a series of jumps. While the basic
brush types alone provide a wide variety of effects, each brush can be
further customised by adjusting its size and opacity and softness. A
selected texture can also be applied without disturbing the existing
colours on the canvas.
9.2
ÉRoughoutæ provides pencil and ink-pen effects at full opacity, the
latter giving a calligraphy effect in the shape of a line that starts
thin and gets progressively thicker.
9.2
ÉMultiple brushæ allows further brush shape variations which, by
selecting the clone sub-option, can be used to add pointillist or
impressionist effects to an existing image.
9.2
ÉHSVæ allows an existing image to be toned.
9.2
ÉAdd Wateræ, ÉSmearæ and ÉDirty Brushæ are all fairly self-explanatory
and provide a variety of ways of softening hard edges and applying yet
more painterly effects.
9.2
ÉFXæ allows the brush to apply a variety of pre-set or user-defined 3╫3
convolution matrices which can be used to sharpen or blur the images as
well as locally applying effects such as embossing and bas relief.
9.2
ÉMagic Brushæ will be familiar to those who have used earlier Artisan
incarnations. It allows up to 64 preselected colours within the image to
be changed, by the brush, to a new colour.
9.2
Holding down <ctrl> turns any of the brushes selected into an eraser to
undo what has just been painted. It only erases anything painted since
the last menu or palette selection, so any previous brushwork is
preserved.
9.2
Also on the paint menu, but Ö unlike the other options Ö not applied
with a brush, is ÉFillæ which provides plain and graduated colour fills
as well as the ability to stretch a sprite to fit a given shape.
9.2
Although ProArtisan 24 does not, at present, support pressure sensitive
graphic tablets, I found that the relatively cheap Tabby graphics tablet
provided a useful alternative to the mouse, and those used to
conventional painting may find it a more natural way to manipulate these
brushes.
9.2
The draw menu
9.2
The items in this menu make use of the Draw module resident in the RISC
OS operating system ROM to deal with geometric shapes such as lines,
curves, ellipses, polygons, rectangles and also text. Text is not anti-
aliased, owing to problems associated with anti-aliasing over multi-
coloured backgrounds. If necessary, the anti-aliasing filter from the
effects menu can be applied to smooth out the edges.
9.2
As well as being able to use these draw objects in the usual way, with a
choice of line width and line and fill colours, you can also render the
outlines in any of the paint styles with any of the brushes. So, for
instance, you can choose a font, type in some text and then have it
rendered as if its outline were drawn with charcoal. Similarly, you can
bring new life to old vector clipart by importing it as a Draw file and
rendering it in the style of your choice. Once drawn, itæs not possible
to edit these shapes within the application.
9.2
An alternative convenient way of dealing with vector graphics would be
to create and edit them initially within Draw and then import them into
ProArtisan 24 for rendering. The latest version of ProArtisan 24 has the
option either to render imported drawfiles exactly as they would appear
in Draw, including sprites, text and fills, or to render them in the
chosen style, in which case sprites, text and fills are ignored.
9.2
The input/output menu
9.2
As well as saving pictures in standard Acorn sprite format, it is also
possible to save them compressed in a non-destructive manner, using
Acorn Squash format. If greater compression is required Ö for instance,
so that they may be stored on a floppy disc Ö and if a small loss of
detail can be tolerated, JPEG compression is also available. This is
probably not a good idea if the picture is likely to be re-loaded into
ProArtisan for further manipulation Ö repeated compression and
decompression is likely to lead to unacceptable degradation.
9.2
User defined palettes and brushes can also be saved for future use.
PhotoCD, drawfiles and just about any file format which is recognised by
ChangeFSI can be imported. At the time of importing, the image may be
scaled and have its gamma changed, along with the other ChangeFSI
processing options.
9.2
The sprite menu
9.2
A sprite, in this context, is defined in the manual as an area of the
screen which may vary from a single pixel to full screen size. It may be
rectangular or of irregular shape and may either be cut from the main
canvas or loaded from an existing file. The sprite pool can contain a
number of such sprites which may then be applied to the canvas in many
different ways. For instance, there are comprehensive blending
facilities for smoothly incorporating a sprite into the main picture.
Perspective and spherical distortion, rotation and scaling are among the
other options.
9.2
The frisket menu
9.2
A frisket is traditionally a piece of paper or card temporarily placed
over a painting to act as a mask and is used extensively in airbrush
work. ProArtisan 24 provides a software equivalent which can be used
during painting and image processing operations. Unlike its traditional
counterpart, it can have 256 levels of transparency, ranging from total
masking, which means that the area covered is protected from the current
action, to none at all.
9.2
There are a number of ways to create a frisket, the most common being to
use either a brush or the drawing tools. The fill function can be used
to give very smoothly graduated masks. It is also possible to use the
entire red, green, blue components or derived grey level of the canvas
to create a frisket, or to add or subtract these values from an existing
mask. During creation, the frisket can be displayed in any chosen colour
Ö by default, red. When actually in use as a mask, the frisket is
hidden.
9.2
Friskets have many uses with this type of application, particularly when
they can be generated in such a wide variety of ways. Typical examples
would be selectively brightening, darkening, sharpening or toning part
of an image. With variable transparency, it becomes a very powerful tool
indeed and needs some practice to take full advantage of it.
9.2
This is probably a convenient point to mention ProArtisanæs all-
important Éundoæ button. It provides a more universal undo function than
the undo brush. If any operation doesnæt produce the desired result, you
can always revert to the previous status of the canvas and try again.
With the paint menu selected, holding down the control key gives you an
undo brush so that just part of an image can be undone.
9.2
The process menu
9.2
All of the image processing effects, mentioned briefly above in
connection with the Paint menu, are available to be applied to the whole
image, together with several others, including a range of filters. Among
the latter are anti-alias, darken, lighten, contrast, tint, colour shift
and grey shift. Many of these are invaluable for improving the
appearance of PhotoCD and other photographic images. If this is your
area of interest, a bit of time exploring exactly what they can do will
be time well spent. I particularly liked the halftone option which uses
a fractal pattern to give a sort of mezzotint effect, rather than the
more usual regular dot pattern which I had expected.
9.2
In conclusion
9.2
As we have come to expect from software written for Acorn machines,
ProArtisan 24 offers excellent value for money Ö particularly when
compared to similar PC software. There are a whole lot of features in
addition to those I have mentioned. It can be warmly recommended to
anyone seeking a general purpose 24-bit painting application which will
allow both the processing of existing pictures and the origination of
new artwork Ö and which can be expected to get the best out of the
RiscáPC.
9.2
The wide variety of painting styles, which can also be applied
retrospectively to drawn objects, together with the very versatile
masking functions, are particularly appropriate to the creation of
original artwork. Anyone with traditional painting skills, wishing to
extend them to the screen, would be unlikely to find another package
that offers such a wide range of tools.
9.2
There are two main restrictions which may cause a minority of users to
look at other packages. Firstly, there is the restriction in canvas size
imposed by the absence of a virtual memory system (which substitutes
hard disc space for RAM), although I understand that Clares do intend to
implement virtual memory in a future release. It could be argued that
anyone producing a lot of big pictures would find it desirable to
purchase the extra RAM for the sake of speed. Few of us can yet afford
the sort of colour printers which would do justice to such high
resolution pictures Ö if we could, the cost of RAM would no doubt appear
to be relatively trivial.
9.2
Secondly, the ability to respond to a pressure sensitive graphics tablet
may be felt to be important by some potential users. Again, Clares are
looking at the possibility, so it may well be available in future. These
two factors are most likely to affect professional users and certainly
should not deter anyone else from considering the package.
9.2
ProArtisan24 costs ú169.95 inc VAT (or ú155 through Archive) and site
licences are available at ú499 +VAT for primary and ú699 +VAT for
secondary (ring NCS for site licences discounts).áuá
9.2
Comment Column
9.2
Acornæs new operating divisions
9.2
(Press release: 12th September 1995) Ö Acorn Computer Group plc has
today announced the formation of two new operating divisions, Acorn
Education and Applied Risc Technologies, as part of a fundamental
restructuring of its core business activities. The restructuring, which
will allow the Group to focus its business more clearly on meeting the
demands of specific markets and customers, follows the appointment of
David Lee as managing director of the Group on 28 July 1995.
9.2
Acorn Education will build progressively on Acornæs education market
leadership and strong brand reputation to increase its UK market share.
Although overall staffing levels will be reduced within the Acorn Group,
the number of staff dedicated exclusively to education will increase.
Acorn Education will continue to focus on the sale of RISC OS-based
computers, but will seek to reduce Acornæs dependence on hardware sales
only by providing schools with a broader range of value-added services,
software and specialist products based on other industry standard
technologies. Mike OæRiordan, sales & marketing director of Acorn
Computers Ltd (ACL), will head Acorn Education.
9.2
Applied Risc Technologies will design and develop advanced products
based on ARM technology. It will continue to develop for Acorn Education
but will also seek opportunities with leading OEMs to exploit its
expertise in silicon integration and hardware and software design based
predominantly on the ARM microprocessor. Applied Risc Technologies, will
be headed by Peter Bondar, who has recently joined the ACL board as
technical director.
9.2
As a result of the restructuring approximately fifty positions have been
made redundant. During the next month, Acorn will be interviewing those
whose positions have become redundant to help them find alternative
employment internally or elsewhere.
9.2
Acorn Corporate Affairs.
9.2
Acornæs new operating divisions Ö So, what does it all mean? You may
have heard rumours flying around, e.g. öIt looks to me as if Olivetti
have, due to their own losses, decided to cut losses at Acorn. RISC OS
and Acornæs own desktop machines will no longer be developed, and Acorn
will sell PC clones to education Ö things are looking very bleak
indeed.ò
9.2
In a word Ö rubbish! The press release above makes it clear that Acorn
Education öwill continue to focus on the sale of RISC OS-based
computersò and ARTæs main customer is Acorn Education. So if either or
both divisions are to continue, there must be some RISCáOS-based
computers developed by ART for AE to sell.
9.2
Acorn have already proved to their own satisfaction that, even with
formerly non-Acorn schools, they can sell RISCáOS in preference to Mac
or PC in head-to-head sales battles. Since Acorn, presumably, make more
money by selling their own machines than they would by branding PCs, why
would they switch to selling PCs?
9.2
Ah, but they have already switched to PCs! The new School Server uses an
off-the-shelf PowerPC computer! OK, but all that proves is that, as with
the Pocket Book, Acorn are not so blinkered that they try to use their
own technology in areas where some alternative technology will do the
job better. As long as they make money by selling School Server and
Pocket Books and as long as it doesnæt detract from sales of RISCáOS
machines (and SS and PB actually enhance RISCáOS machines sales), why
should they not use other technologies?
9.2
School Server is a prime example of how Acorn continue to give the lie
to the Éindustry standardæ myth. Acorn has always been ahead of the
bunch in file transfer between machines. Apple and PC have always tended
to insist that everybody should Édo it their (standard) wayæ and not
offered file transfer. Manyæs the time I have helped people to transfer
files from PC to Mac and vice versa by using a RISCáOS machine! OK, Macs
are now offering some sort of PC Écompatibilityæ but at a massive
Émemory costæ. Acorn is benefiting from the fact that it has never
suffered from the Édo it my wayæ syndrome and, in School Server, has
provided exactly what schools need Ö the flexibility to use different
machines under one roof Ö and itæs Acorn that is making it possible, not
PC or Mac. Long may Acornæs Éopenæ attitude continue to be recognised
and supported by open-minded school heads and governors!
9.2
Having said all that, my guess is that Acorn will have some own-brand
PCs that customers can buy from them if they prefer PCs but, hopefully,
they will be PCs with an easy link to RISCáOS so that schools are still
within reach of the kind of OS that many people accept is so much more
appropriate for education. Still, I think the days are gone when Acorn
could hold the moral high ground and insist on keeping themselves
Épureæ. These days, they have to do whatever they can that makes money.
Thatæs just plain cold hard economic sense.
9.2
Ed.
9.2
Educational admin with Acorns Ö We have used Acorn computers for
administration at Northampton High School for a number of years
although, initially, this was just word processing using BBC Computers
and dot matrix printers.
9.2
We now have a Nexus network of Acorn A5000/Risc PC computers throughout
the school being used for curriculum and administration. The secretaries
are able to produce a variety of good looking documents using Impression
Publisher and Easiwriter, printed out on Laser Direct printers.
9.2
In the last two years, we have set up a pupil database using Iotaæs
Datapower. One computer is dedicated to act as a database server and all
the other computers can access this database at different levels of
security, depending on the password used. Datapower is so flexible that
different layouts of data can be made available, or not, to different
users.
9.2
For example, all the staff can access form lists with a general
password, Science staff can access a record of A level chemistry
coursework marks and update them with a different password. The
secretarial staff have a whole host of layouts available, such as
medical information, dinner passes, address labels etc.
9.2
From the database, we can easily produce new layouts when a new
requirement is discovered. Recently, we saved out some of the database
data in CSV format to load into the library management system (PC), and
we also printed off library tickets. We use a similar method to provide
CSV data for the exam entry system which is also a PC.
9.2
The database also records whether parents wish their name/telephone etc
to be published in a School year book. The data can then be easily
extracted to produce the year book.
9.2
We have now purchased an OMR machine from DRS and await the OMR software
from Iota. This will allow us to investigate many other administrative
tasks such as recording attendance and keeping more assessment records
electronically. We are an independent school and have a multiple choice
answer sheet as part of the entrance examination. It is hoped that the
OMR machine will make the marking of this much easier.
9.2
We chose Acorn, and particularly Datapower, for our administration
because we already had a Datapower site licence and many Acorn machines
around the school with quite a lot of expertise and support in their
use. It seemed silly to get a different computer system and pay several
thousand pounds for software and support (such as SIMs), when we could
build our own system simply which would be tailored exactly to our own
requirements.
9.2
Our accountant continues to resist all forms of computerisation, yet he
does an excellent job with a manual booking system.
9.2
I would be happy to take further queries on our computer system or
demonstrate it to visiting teachers.
9.2
Tim Hoddle, Northampton High School, Hardingstone, Northampton NN4 6UU,
(01604¡765765).
9.2
Icon Technology Ö I do not feel that EasiWriter gets enough credit in
Archiveæs columns compared with Impression or Wordz / Fireworkz. As a
book publisher, I do not need many page design facilities, but I do
require good text and document handling facilities. In its latest
incarnation, EasiWriter Professional, it is without doubt the most
powerful document handling program available for RISCáOS, and the only
one that really bears comparison with PC or Mac Éindustry standardæ word
processing packages. I also use Impression Publisher for some
applications and, in my experience, EasiWriter is by far the easier to
use (even if the more advanced structure styles remain tricky), and it
does handle many of my graphic requirements for publication.
9.2
For example, a recent job went direct to an electronic printing process
run by Macs and PCs. Files were simply exported on DOS discs as
PostScript, loading a dummy HP Laserjet definition file into !Printers,
and selecting ösave as PostScriptò from the EasiWriter save menu. The
process (on a Risc PC) took a few seconds for each (~1.4Mb) file, and
the whole job including text and graphics reproduced first time with no
hitches. Compare this with the complexities and uncertainties of
obtaining a PostScript file in Impression Publisher.
9.2
One final plus point for Icon. On the very few occasions when I have
needed to contact them (EasiWriter is now very robust), they have helped
me immediately, courteously and effectively, which is not always true of
CC! I am not knocking Impression which remains for the moment the
essential page layout tool but, in my comparative experience, for
straightforward jobs (like, dare I say, Archive magazine), EasiWriter
offers a quicker, friendlier and more powerful alternative.
9.2
John Hurley, Cheltenham.
9.2
Online Media wishlist Ö If Acorn succeeds in getting a position in the
market for boxtop digital television converters, I should like them also
to provide a bundle that would enable the box to be used as a souped-up
A3010. This would provide cheap Éportabilityæ to wherever a television
set is available.
9.2
It would be an alternative use for the A7000 board design. I believe
that such cheap quasi-portability of this kind to wherever there is a TV
would cover 75% of the use that is normally made of expensive battery-
powered A4 machines.
9.2
There would need to be a floppy drive to carry files to and from oneæs
main machine, and a small (50Mb?) hard disc. I do not see any need for
video RAM. The operating system would need to provide suitable modes for
the typical low-definition TV screen, and though a cut-down RISCáOS
would be adequate, it is probably simpler to leave all the modules in.
The screen would probably need to be further away from the user, and
therefore from the keyboard and mouse/tracker ball, so I should like to
see wireless rather than wired connection.
9.2
Presumably, the existing converter would have the facility to drive
differing national television standards, so such a machine could be
Éportableæ internationally. I do not see that the extras needed would
put the cost up by more than ú100-200.
9.2
Apart from the use I, and I should think other Archive readers, would
find for this, it could do much to spread the Acorn word.
9.2
John Laski, London, SW1.
9.2
SCSI problems? Ö Donæt let the reported problems with the Cumana SCSI 2
interface put you off using SCSI devices. I value reliability above raw
speed and have used the Oak SCSI interface for five years with no
problems whatsoever, at up to about 1.85Mb/sec in mode 0 with a 270Mb
drive and an ARM3. It drives SyQuest exchangeable drives superbly Ö even
to ejecting them on dismount. But check CD compatibility with Eesox
before purchase. The new suppliers, IFEL, are in my experience very
helpful and efficient.
9.2
Stuart Bell, Horsham.
9.2
Windowsá95 Ö Now is the time to strike! I am sure that, like me,
everyone has read reviews in the papers about Windows 95. Now, ignoring
that atrocious stunt pulled with the free copy of The Times, it would
seem that most of these reviews compare it unfavourably to older Macs.
Nowhere have I read about Acorn machines in comparisons. Iáfeel this is
neglectful not only on the part of the papersæ technology editors but
also on the part of Acorn. Surely Acorn should be pushing ads into these
computing sections extolling their virtues? Call me a na∩ve consumer but
I would have thought that an ad that mentions ease of starting, user-
friendliness, cost and efficiency placed next to a less-than-
enthusiastic review of Windows 95 would do wonders. Why do we never see
Acorn ads in the mainstream media?
9.2
I also feel it is up to us, the enthusiasts, to write to these papers
bemoaning their lack of interest. At the least it will cost 4╫25p stamps
to the broadsheets and may help raise Acornæs profile, especially since
they seem little interested in doing it themselves. In fact, why donæt
all of you Netters get into action? All of the broadsheets have email
addresses.
9.2
I realise that these letter pages are generally more concerned with more
technical topics but I do feel that unless we take our head out of the
sands and take the fight to the opposition we will be squeezed away to
nothing.
9.2
Gavin Dobson, Shropshire.
9.2
I think itæs time to call a halt to all the Win95 versus RISCáOS
discussions in Archive. Space in the magazine has been at too much of a
premium of late. I hope you will agree that the number of good technical
articles is increasing. Please keep those articles coming. Actually, it
has happened at a time when advertising has virtually stopped. We donæt
sell advertising but merely allow people to advertise if they wish (ú150
per page) This means that you get more info for your money... but I get
less! I feel a price rise coming on! Would you mind paying a bit more?
Do you think it is good value at ú22 for 12 issues (UK)? How about
ú28?áuá
9.2
Programming Workshop
9.2
Colin Singleton
9.2
This monthæs column is all about averages, and I have deliberately used
this general term rather than the more precise mathematical term mean.
Users of Stock Control and Sales Analysis applications often need to
know the level of turnover of each product, or each customer, or each
combination of the two, in order to plan future stock purchasing and
marketing strategy. To provide this information, records need to be
kept. Assuming that we do not wish to retain indefinite records of
individual sales (repeated analysis of which would be very time-
consuming), what summary figures do we need to compile in order to be
able to calculate the required averages? There are several possible
calculations.
9.2
Annual turnover
9.2
Assume we have two analysis fields on the database record for each
product, or whatever. One is labelled Total-sales-last-year, the other
Total-sales-this-year. During the accounting year, sales of the product
are totalled in the second field. At the end of the year, that figure is
copied to the other field, and the current year figure is zeroised ready
for the new yearæs figures.
9.2
When we wish to analyse sales, we can calculate average monthly or
weekly sales for last year simply by dividing by 12 or 52. To obtain the
average sales this-year-to-date we divide the total by the number of
months or weeks which have passed in the current year. This is
straightforward, and it only requires two fields on each record. That
can be important if we have a very large number of records.
9.2
This calculation has its disadvantages. The average of two weeksæ sales
must be taken with a large pinch of salt, since it is vulnerable to
random variations. A 50-week average does not suffer from this problem,
but it does smooth out seasonal variations and any recent increase or
decrease, which we may wish to see. The figures printed under the
heading Average-year-to-date therefore require different interpretation,
according to the time of year, and may confuse the unwary user. We
cannot compare this yearæs turnover with last yearæs, except at the end
of the year, because figures based on a part-year cannot meaningfully be
compared with those for a full year.
9.2
Rolling average
9.2
This technique homogenises the above calculation, permitting a uniform
interpretation. We total the sales of each product in each month and
retain on each record the totals for each of the last twelve months
separately. Each month we drop the oldest figure, slide the others back
a month, and clear the last figure for the new monthæs total.
9.2
The Rolling Average printed on our analysis is simply the average of the
twelve figures on the record. It is the average for the twelve months to
the latest month, irrespective of the accounting year. Since it always
averages a full year, it is not vulnerable to short-term freaks, or to
seasonal variations. If we hold 24 monthly figures on each record,
instead of twelve, we can always compare the current average with the
corresponding figure a year ago.
9.2
One disadvantage of this calculation is that an average of the last
twelve months is slow to respond to any changes of sales pattern. We can
resolve this problem by calculating the average of the last three months
(say), and the corresponding figures last year if available, alongside
those for the full year. This will give a more up-to-date picture, and
will reflect seasonal variations, if any.
9.2
The real disadvantage of this technique is that it requires 24 figures
on each record instead of two. If you work for a company which sells
6000 products to 30000 account customers (as I once did), and you wish
to analyse who-buys-what, you will need a lot of disc space! With
tumbling disc prices, this is much less of a problem than it once was,
but must still be recognised. The processing time of the monthly roll-
down run will also be significant.
9.2
Exponential smoothing
9.2
Sounds interesting Ö what does it mean? It is a technique which attempts
to solve several problems at once, and only requires one historical
figure on each record! This figure is essentially a Monthly Average, but
it is not the simple average of any specific twelve months (or any other
number). At the end of each month we multiply the Average figure by 85%,
and add 15% of the latest month total. We may use different percentage
figures, provided they total 100.
9.2
This figure is a form of weighted average. The rolling average comprises
81î3% of each of the last 12 months figures. The smoothed average
comprises 15% of the latest month, 12.75% (=15%╫85%) of the previous
month, 10.84% of the one before, etc, ad infinitum. Using the 85/15
split, the effective age of the smoothed average is the same as that of
the 12-month rolling average (i.e. six months), but it nevertheless has
an in-built bias towards the more recent figures. This means that it
responds more quickly to changes in trend. It also, to some extent,
reflects the seasonal factor of the current time of year. This
calculation does not provide a comparison with last year, but you canæt
have everything!
9.2
You pay your money and you take your choice. This used to be called
System Design Ö you design your computer system, particularly the data
structures, according to what you want out of it. This has to be done
carefully, or you may find later that you cannot obtain the analysis you
need because you did not start collecting the right data two years ago!
From the lack of demand for my services, it seems that systems arenæt
designed any more! No wonder so many users (of bespoke systems) have
problems.
9.2
Enough of the sour grapes. Next month, I will give a practical
demonstration of the above concepts which will be of interest to at
least some Archive readers.
9.2
I am always on the lookout for new ideas. Please send any comments or
suggestions for this column to me at 41 St Quentin Drive, Sheffield, S17
4PN.áuá
9.2
Cumanaæs Proteus Drive
9.2
Ted Lacey
9.2
For some while now I have been noticing the rapidly dwindling amount of
free space on my RiscáPC 600 hard disc. With the receipt of the long
awaited PC486 Card, this shortage became a real problem. In addition, a
faster CD-ROM drive was required.
9.2
The options that were open to me had to be considered carefully. A
second hard drive? The RiscáPCæs limitation of two IDE add-ons settled
one point quickly; you canæt have an inexpensive IDE hard drive as
advertised in Archive Magazine and a CD-ROM drive with an IDE interface.
So I started looking at SCSI items, as it was obvious that I would have
to install a SCSI card, with future expansion plans in mind. As I needed
to back up a lot of the data on my 410Mb hard disc, I decided to
investigate the cost of adding around 1Gb of storage media.
9.2
Three options were considered...
9.2
(a) The Proteus drive and two PD Optical discs of 650 Mb (1.3Gb). This
drive reads optical discs and is also a quad speed CD-ROM drive, only
occupying one slot on the front of a RiscáPC. An external version is
available at extra cost.
9.2
(b) A removable hard drive, such as those advertised by Pineapple
Software, plus a quad speed CD-ROM drive.
9.2
(c) A 1 Gb SCSI hard drive and a quad speed CD-ROM drive.
9.2
As all options required a SCSI card, the cost of this was not considered
in the calculations. Option (c) was soon discounted as being too costly
and having no future expansion capability.
9.2
The costs of (a) and (b) work out about the same with the Proteus and
two PD Discs providing about 0.3 Gb extra memory. However, for anybody
with a single slice RiscáPC, there would be the added cost of a second
slice for the Pineapple setup. The initial cost could be even less, as
VTIEclipse are running a special offer at around ú70 less than Cumanaæs
price for the Proteus. Also, I reckoned that the 650 Mb PD Discs Ö about
the size of a CD-ROM plastic case Ö would be easier to store than the
removable hard drives. So option (a) won the day and my order for the
internal version went to Archive.
9.2
Installation
9.2
On unpacking, I found that, in addition to the drive, there were two
floppy discs, Cumana CDFS Soft, and Acornæs PhotoCD sample application
and a ribbon cable. As I had ordered a SCSI2 board at the same time, I
also had a further floppy, Cumanaæs SCSI Utilities disc.
9.2
I found no real difficulties with the installation except for one point.
Cumanaæs Useræs Guide for the Proteus drive emphasizes the correct
installation of the ribbon cable between the board and the drive,
stating öensure pin1 to pin1 connection or damage may result.ò With the
aid of a torch and a magnifying glass, I was able locate pin 1 on the
SCSI board, but there was no indication on the connector at the rear of
the drive. Aácall to Cumanaæs Technical Support produced the information
that pin 1 on the drive is located at the end nearest to the power
socket. I suggested to them that it would be a good idea if the drive
itself showed the pin layout or, alternatively, that the User Guide
diagrams showed this information. Installation was completed by adding
the driver from the CDFS Soft disc to the !Boot file. The user guide
contains instructions for fitting external versions as well as
instructions for a setup using RISC OS version 3.1. There are also notes
for connecting an optional audio board. I have delayed adding the extra
sound facility for the time being, as I understand that there are new
products in the pipeline.
9.2
Overall, I found the installation easy and the instructions in the user
guide adequate, apart from the pin 1 business.
9.2
In operation
9.2
Carrying out the tests in the guide soon informs you if you have
everything connected up correctly. This being so, inserting a RISC OS
CD-ROM in the drive and carrying out a few tests will tell you if all is
well.
9.2
Next, using the !SCSI Manager application on the Utilities disc, you
have to format the PD disc Ö read the handling precautions shown on the
disc. The first surprise was the SCSI Manager telling me that the disc
only had 634Mb of memory! (See Jim Nottinghamæs PC486 article in Archive
9.1 p41). I suggest that you read the !Help file first or even make a
printout to understand the finer points of formatting. I found it quite
easy, but a word of warning. Unlike formatting a floppy disc, any
defective sectors are not shown individually, but you just get a general
warning at the end telling you that they will be mapped out. I got this
the first time I formatted and I chose to ignore it. The result was some
slowing down and sounds of Éhuntingæ from the drive. I decided to re-
format the disc and got a clean bill of health on verification. End of
problem.
9.2
At this point, a decision has to be made on the number of partitions
that you require. I tested the media by creating the maximum of four
partitions of different sizes Ö this gives four SCSI icons on the
iconbar. You can rename them from the iconbar menu if you wish.
Inserting a subsequent disc with, say, only two partitions, does not
change the iconbar, but when changing discs you must dismount from the
SCSI icons, otherwise the name you have chosen will not change and you
will get menus from the previous disc. It does not appear to be possible
to change the size of partitions at a later date without losing data
stored on the disc. You can copy from one disc to another in the same
way as copying from a floppy disc. But, as you are handling large
amounts of data, get the kettle on and be prepared for a lot of disc
swapping!! At the moment, the only way I can see to speed this process
and to change the size of partitions, is to copy in sections via your
hard disc. Careful thought of your requirements is needed before
partitioning a PD Disc.
9.2
In use, I found that access appears to be as fast as from a hard drive.
An approximate rate of transfer from hard drive to PD Disc is in the
region of 9Mb per minute. Transfer of data from one partition to another
on the same disc is quite fast.
9.2
Conclusions
9.2
From the limited use that I have had so far, the Proteus drive is good
value for money and meets my requirements. In the long term, the thought
of adding an extra 650Mb of storage for under ú50 appeals to me very
much. I did have some software problems with the drive in respect of the
PC486 Card, which I eventually solved. As these do not appear to be
specific to the Proteus, I have sent details to the new RiscDOS editor,
Michael Clarkson.
9.2
The Proteus drive costs ú635 (internal) and ú805 (external) through
Archive, and the 650Mb cartridges are ú50 each.áuá
9.2
Graphics Column
9.2
David Thornton
9.2
Welcome to to the Archive Graphics Column which I hope will inspire you
into using your Acorn computer for graphics. I expect that nearly
everyone will have experimented with graphics in some way, even if it is
just by using Draw and Paint. I personally believe that DTP and graphics
are the two most important markets for Acorn computers outside of
education. It is therefore vitally important that these markets are
exploited to the full by Acorn developers, in the same way that Adobe
and Quark have been doing with Apple for years.
9.2
Erratum
9.2
In my column last month, two of the pictures were inadvertently swapped
Ö the BMP/DIB Translator v1.01 picture (p36) and the ImageFS 2 save
window (p37). (My fault, sorry! Ed.)
9.2
ImageFS update
9.2
Alternative Publishing has cut the price of ImageFS 1, its transparent
image import application to just ú24.95 +VAT (ú28 through Archive).
ImageFS 2, previewed last month, will also be able to export in many
bitmap formats, and also includes Universal Image, an application for
cataloguing images and obtaining detailed information on their
specification. This will be available in the not-to-distant future at a
cost of ú39.95 +VAT. Owners of version 1 will be able to upgrade for ú20
+VAT. A site licence version will cost ú99.95 +VAT and to upgrade from
the original site licence version will cost ú49.95 +VAT.
9.2
Impression update
9.2
There is to be a new version of Impression Publisher which fixes some
memory-related problems on the Risc PC, contains improved printing
techniques for use with the TurboDrivers and also includes some of the
Publisher Plus features, such as word count and case swap on selected
areas.
9.2
Future columns
9.2
I have ideas for a number of future columns, but would welcome your
ideas.
9.2
Å  ArtWorks Ö incorporating a review of the Arranger tool and discussing
its future in relation to Xara Studio (CC say they are doing Xara Studio
for RISCáOS = ÉArtworks Proæ. Ed.)
9.2
Å  Porting EPS files between platforms and manipulating them under RISC
OS.
9.2
Å  Continued features on graphic file formats and exchanging data
between platforms.
9.2
Å  Colour tables Ö what they do and how they work. Impression, ArtWorks
and the TurboDrivers, as well as some bitmap editors, use them. You can
also create them with SepEd2 if you have TurboDrivers 4.03.
9.2
Å  New tools for ArtWorks (please write to me if you are developing
any).
9.2
Å  Graphics in education. I only know a little in relation to primary
school software so contributions from schools or educationalists are
very welcome.
9.2
This list is in no specific order and is subject to change. I am not a
professional who makes a living by using Acorn computers for graphics
but I own a number of Acorn graphics applications myself and have worked
with a number of software companies, beta testing their products. While
I am writing this column, I will also be learning about graphics
techniques. I am not a total beginner Ö I do know quite a bit about
graphics but do let me know if I make an important mistake or if you
feel that you could explain something better than I have.
9.2
File formats
9.2
Alan Wilburn commented that there isnæt currently anything available to
convert CorelDraw (CDR) files to RISC OS. The problem exists because
there arenæt any vector/meta applications for RISC OS which could
actually handle all of the CDR formatæs contents. I have been told by a
developer that they are experimenting with a program to convert CDR
files to EPS (Encapsulated PostScript) files. These could then be
imported into ArtWorks. The WMF, CGM and other vector/meta format
support is very lame and needs improving. Even though Keith Sloanæs
careware converters are good, I do not like to rely solely on non-
commercial software for such an important task. I also donæt see the
point of purchasing large, expensive applications such as Oakæs Draw
just to perform a conversion. There is an obvious market waiting to be
filled here.
9.2
For some months, I have been working with Alternative Publishing and
other developers to establish a standard set of graphic file formats. I
have collected together around forty bitmap formats and getting on for
twenty vector/meta formats. I have also collected brief information
about each format, as many icons as possible, as many DOS and Mac maps
as possible and the filetype name and hexadecimal number.
9.2
All of this data will be compiled into a stand-alone S¡Base application
and distributed somehow. I donæt mind bundling it with commercial
software if any developer is interested. I have already had a positive
response from software developers who have seen the product and I
believe that it will be immensely useful when it is finished (which
should be soon).
9.2
Macintosh file exchange
9.2
Whilst it is possible to use a PC disc as an intermediate medium for
transferring files between Mac and Acorn, this can be inconvenient,
because some Macs are unable to read PC discs. What the Acorn needed was
an application to allow native Macintosh discs to be accessed by Acorn
computers. Three commercial products exist to allow you to do this: CCæs
MacFS (ú99 +VAT or ú108 through Archive) and MacFS Light (ú49 +VAT or
ú53 through Archive) and Oregan Developmentsæ AppleFS (ú59.95 inclusive
or ú58 through Archive).
9.2
All of these applications allow an Acorn computer to access 720Kb and
1.44Mb floppy discs, but MacFS also allows you to read Macintosh SCSI
discs, such as hard discs, SyQuests and possibly CD-ROMs. It should, in
theory, allow you to access Macintosh IDE devices but CC have not tested
this yet.
9.2
AppleFS
9.2
AppleFS comes in a well-presented box encased in a sleeve which contains
a floppy disc, an eight page manual and a registration card.
Installation requires you to enter your name before you can copy the
application to hard disc. When you load AppleFS, anáicon will appear on
the left hand side of the iconbar because it is actually a separate
filing system, similar to MultiFS and PCDir, and so to access Mac discs,
you click on this icon rather than the normal floppy icon.
9.2
The AppleFS iconbar menu contains options to dismount and to format a
disc. It is of course possible to have more than one Macintosh disc
mounted at the same time and it is also possible, and useful, to be able
to select which disc to dismount rather than only being able to dismount
the last mounted disc. A third option, labelled öChoices...ò, displays a
filetype mapping window in which Macintosh files can be mapped to Acorn
files, and vice versa, by using the following dialogue box:
9.2
An option, unique to AppleFS, is the convert text tick box. This option
allows you to set whether text files are converted, in terms of their
appropriate character sets, when transporting between the Acorn and
Macintosh platforms. The conversion process involves mapping characters
between the two platforms and converting carriage returns to linefeeds,
and vice versa.
9.2
The file mapping is very easy to set up, with a radio button to select
whether you wish to map Mac files to Acorn files or Acorn files to Mac
files. Every RISC OS filetype has a three character hexadecimal code and
there is a maximum of eight characters for the textual name and each
filetype must also have an icon.
9.2
Mac files, however, work in a slightly different way. Each file usually
contains two sub-files known as the resource fork and the data fork. The
data fork is usually the data that you will want to use and the resource
fork usually contains information about the data and how to utilise it.
Macintosh maps are always four characters. Some may use spaces to make
up the four digits (e.g. PCX_, where I use a _ to indicate a space).
9.2
To map a Mac file to an Acorn file, you must either select an existing
source map or create one yourself. To select an existing one, simply
select it from the scrolling source list and then select a corresponding
RISC OS filetype from the target list. If either of the source or target
maps does not exist, you just click <menu> over the relevant pane,
choose add, and enter either the required Mac or RISC OS filetype. Once
you have set up all your required mappings, you can save them for later
use, so you should not have to enter them again. A default set of
mappings is included with AppleFS.
9.2
An AppleFS disc window is different from a standard RISC OS filer
window. You are not able to change how files are displayed or sorted and
it is only possible to copy files, not rename, count, delete or stamp
them. There are two menu options for displaying information about the
disc and any selected file. You can also toggle whether the data and
resource forks are shown or not and it is possible to create a new
directory. AppleFS displays Mac filename characters correctly including
full stops (this is the advantage of using a separate Mac window rather
than the standard RISC OS one), although filenames are truncated to a
maximum length of 16 characters out of a possible 32 in the AppleFS
window.
9.2
MacFS and MacFS Light
9.2
These are both distributed in a CD style case which contains a single
floppy disc and a manual. Both versions are identically packaged and
installed. MacFS Light is simply a cut down version of MacFS that is
unable to read Mac SCSI devices. The way that MacFS accesses Macintosh
discs is totally different from AppleFS. On loading the application, no
icon appears on the left of the iconbar, only a banner to indicate that
MacFS has been loaded.
9.2
MacFS discs are treated in a similar way to RISC OS and DOS discs.
Clicking on the disc drive icon will open a Mac disc, and the filer
window can display all 32 characters of the  file name. When
transferring a Mac file to a RISC OS formatted disc, all spaces are
converted to hard spaces (character 160) and É.æ becomes ÉÅæ. All Mac
files are displayed as a special MacForks filetype, unless the file has
already been mapped to a RISC OS filetype using the MacMap command.
Double-clicking on a MacFork file opens an additional window containing
the data fork and, if present, the resource fork and an eight character
identifier. This consists of the first four characters for the filetype
and the second four characters for the application which created it.
9.2
Formatting discs to Macintosh 720Kb or 1.44Mb formats is done in exactly
the same way as formatting a DOS disc. Two additional Mac formats will
have appeared at the top of the öOther formatsò menu and selecting the
relevant format will format the disc.
9.2
Mapping Mac filetypes onto RISC OS filetypes is performed by typing star
commands, either by pressing <F12> or by using a text editor and saving
the file as an obey file. A standard MacMap consists of something like:
9.2
*MacMap PICT * D &FD5
9.2
The first four characters, in this case PICT, refer to the Mac file. The
second * refers to the origin of the file, indicating that it can have
any origin. The D shows that you wish to copy the data fork as opposed
to the resource fork. The final three characters after the & are the
RISC OS filetype hexadecimal code. Any MacMaps entered into the command
line will not be remembered when the computer is switched off. To ensure
MacFS does remember them when it is loaded, you must add the MacMaps to
the !Run file inside MacFS, using a text editor. This is a bit of a
failing and could be bewildering to first time users. The manual has two
mistakes relating to this but if you know how to open an application and
load a file into Edit, you should have few problems. There are examples
for you to copy and base your maps on. Iáam using version 1.04 of MacFS
and MacFS Light. At the time of writing, MacFS and MacFS Light do not
support MacMaps which contain spaces. Later versions should fix this
problem.
9.2
Conclusion
9.2
It is difficult to choose my preferred application, as Oregan is working
on a major upgrade of AppleFS, due to be released at Acorn World æ95.
Prior to the upgrade, I would have recommended MacFS or MacFS Light.
MacFS does most of what AppleFS does but in a more transparent and
logical way and AppleFS is more intrusive because it is implemented as a
separate filing system. I would like to see MacFS contain a more
intuitive system of setting MacMaps; a separate utility might suffice
for this and the bug whereby MacMaps with spaces cannot be used, needs
to be fixed. AppleFS does not have this bug as it implements mappings in
a different way.
9.2
AppleFS may well also support the reading of Mac CDs and hard discs at
the same price Ö although this is not yet decided. It will also be
converted into an image filing system, so its operation will be similar
to that of MacFS (i.e. transparent, rather than being a separate filing
system). If it did all these things then, with the price remaining at
ú59.95 inclusive, it would sweep into the lead.
9.2
One other advantage of AppleFS, which I havenæt yet mentioned, is that
it will work on 800Kb floppy drives (although obviously only at 720Kb
Mac format) whereas MacFS can only be used if you have a computer with a
1.6Mb drive (i.e. A5000 or later).
9.2
I donæt know whether CC are planning an update for MacFS, so my advice
would be to wait until after Acorn World before making a decision.
9.2
Final comments
9.2
I will be at Acorn World on Friday and Saturday. If you have any
questions, comments or other information for me, do come and have a
chat. I should be around the Archive stand for some of the time.
9.2
If you have ideas, suggestions, questions my address is: 1 Castle Court,
Lower Burraton, Saltash, Cornwall, PL12 4SE. (No telephone calls,
please.) For a reply, please include postage, preferably as stamps.áu
9.2
RiscDOS Column
9.2
Mike Clarkson
9.2
Having taken over this column from Simon Coulthurst, I must begin by
thanking all those whoæve written to me either as a response to my
article on Win95 (8.12 p50) or concerning other Acorn/PC matters.
Perhaps I should also outline the areas with which I think this column
should be concerned Ö and those with which it shouldnæt (though, of
course, Iæd welcome comment on this as on any other aspect of the
column).
9.2
It seems to me that, as Paul wrote recently, we donæt want to clutter
Archive up with PC information which could easily be gleaned from a
straightforward PC magazine, but rather concentrate on (a) connectivity
between the two platforms, i.e. interchange of information of whatever
sort and by whatever means, and (b) problems (and their solutions) which
relate specifically to implementing PC hardware and software on the
Acorn platform. With this in mind, I turn to several issues which have
recently been raised.
9.2
Windows 95 (revisited)
9.2
In the last issue, Mike McNamara warned us not to dismiss Windows 95 too
quickly (9.1 p34); several others have written suggesting the same,
including my predecessor Simon Coulthurst, who is now using a 60MHz
Pentium with 40Mb RAM and says that Windows 95 runs beautifully;
reluctantly, I have to agree that, with that sort of specification
machine, it is a very capable operating system Ö and definitely the
operating system of the future.
9.2
True, it doesnæt run too well on todayæs östandardò hardware, and is
particularly greedy for RAM, but with the price falling all the time,
machines with 16 and 24Mb RAM are going to become much more common; the
good news for Risc PC users, of course, is that there is plenty of
expansion capability in this area, up to a maximum rather larger than
most standard PCs. The ability to plug in a new second processor card
could also make for the most easily upgraded PC as well as a
terrifically upgradable RISCáOS machine. To dream for a moment, 1998
could see a Risc PC with six ARM 800s on a co-processor board, a P6 in
the second processor socket and 200Mb RAM shared between them Ö all in
the box on your desk at the moment; in contrast, most of todayæs 486
boxes will be long gone.
9.2
To return to the present, for those Risc PC users who want to run
Windows 95 now, it looks like 16Mb RAM is going to make for a much more
productive machine, with say 12Mb allocated to the PC card as standard.
Having that amount of RAM also means it really is possible to multitask
platforms, with say 8Mbáallocated to each. As an encouragement,
MráRáColeman has it running on his Acorn 486 card with 24Mb allocated to
it (lucky chap!), and although the 486 is not as fast as it might be, he
clearly finds it quite usable.
9.2
I personally have had little use from Win95 since the school in which I
teach is waiting for a new IT block to open before upgrading. Iæm
therefore probably a little behind on the state of implementation on the
Risc PC. James Pullan has mentioned new drivers and software
configuration, and Aleph One were certainly intending to work on these,
as well as providing full-colour (and sound?) support, but I have seen
and heard little of this so far Ö maybe theyæll be at Acorn World? A
couple of correspondents have also mentioned running Win95 in a
multitasking window which I could not Ö is this a result of a different
setup or new drivers etc?
9.2
PC compatibility
9.2
Almost inevitably, the PC card does not offer 100% PC compatibility (but
then neither do many PCs Ö hence the huge growth of telephone hotlines
for those who canæt get things to work). Neil Dickson wrote suggesting
that something along the lines of Jim Nottinghamæs SCSI card
compatibility chart would be useful, to which I would say a hesitant
öyesò.
9.2
I hesitate because of the huge volume of software there is for PCs, and
because of the various hardware configurations on which it might be
running. Perhaps I might suggest that you let me know if you have had
problems running a major piece of PC software, giving details of the
software version, the PC operating system, and your hardware. I will
then attempt to put together details of these and, with luck, another
reader may have already solved your particular problem.
9.2
As a start, Dave Floyd mentions that Sim City 2000 will not install,
because it cannot determine which graphics card is installed, and Player
Manager 2 installs but wonæt run because it relies on a key-disc being
in drive 0 which it is unable to find (even though the disc is in the
floppy drive). The latter would appear to be similar to a problem I had
when installing Win95 from floppy Ö it seems Microsoft now supply
software on 1.7Mb floppies, with only the first disc being 1.44Mb.
Unfortunately, even with the patch supplied on the 1.44Mb floppy, DOS
was unable to read 1.7Mb floppies in my drive. Fortunately (and
amazingly) RISCáOS was able to do so Ö if anyone else finds themselves
with this problem, the solution is to use RISCáOS to copy the 1.7Mb
floppies to a partition on your hard disc and then install from there,
assuming the software allows you to (Win95 did).
9.2
Ted Lacey wrote mentioning that he has a similar problem. He has a copy
of Tasword on his drive_c partition which loads OK but fails when it
tries to access drive a. If he loads the application from drive a, it
works fine. This sounds similar to the above, but may not be. Does
anyone have any ideas?
9.2
One piece of hardware which I can report does work with the PC card is
the Cumana Proteus CD ROM/removable hard drive when used with the Cumana
SCSI 2 card. Ted Lacey included in his letter the details of how he got
it to work, based on Jim Nottinghamæs Hints and Tips article last month,
which I will pass on to any who would like them (theyære a little
complicated to include here at this stage). The Proteus is a device I
expect to buy in the next couple of months, and one which I would
strongly recommend for others to consider, particularly if you are going
to be using the PC card much, since it offers such plentiful storage.
9.2
Printing from Write
9.2
To add to B Colemanæs comment (9.1 p19) about printing from Write on the
486 card, my experience shows that printing from within the 486 requires
a standard Acorn driver, not a Turbo Driver, and that !PCConfig should
have the öUse RISC OS printer streamò set to LPT1. However, this is when
running the Win95 beta, so may not be of much use. I am planning next
month to look at printing from the 486 card, and will look into more
possible problems and configurations then. Reports from others would be
very welcome.
9.2
Miscellaneous matters
9.2
Ted Lacey also mentioned that, for ú40, he has upgraded MS DOS 3.3,
supplied with the old PC emulator (to MS DOS 6, I guess), and presumably
he uses this in preference to the PC DOS supplied with the card. My
personal feeling is that a Windows 95 upgrade now represents the best
value for money, although it is far from cheap to buy from scratch Ö do
shop around for the best price (with Win95, DOS becomes obsolete).
9.2
Finally, one problem to which I suspect there is no answer (but Iæm
hoping there may be). Most of us who use the PC card will find we
eventually run out of space in the PC partition. What do we do then? Is
there any way of increasing the size of PC partition without creating a
new one? The best I can suggest is to create a new, bigger, partition
using !PCConfig, then copy the whole of one partition onto the other,
and finally delete the first. This clearly would mostly require a lot of
clearing out of Acorn files, possibly to a floppy backup, which could
then be restored.
9.2
An alternative is to connect a high capacity storage device (another
hard drive, SyQuest or Cumana/Panasonic Proteus drive) and use this.
Personally, I think I will be using a Proteus drive with a whole (650
Mb!) disc dedicated to PC stuff.
9.2
Finally, to avoid confusion, we should point out that PC DOS is produced
by IBM, not Microsoft, as Jim Nottinghamæs Hints and Tips article
suggested.
9.2
Thatæs all for this month. Do keep the letters and comments coming, and
also suggestions of areas which might usefully be covered Ö one I have
in the pipeline is printing from the PC card, so experiences,
difficulties and solutions on this would be particularly welcome. My
address is Michael Clarkson, Riggæs Hall, The Schools, Shrewsbury, SY3
7AZ. I can be emailed at [e-mail], which is a school-
wide address, so please include at least my initials in the subject
field so that it gets directed to me.áuá
9.2
Sibeliusá7
9.2
Ian Beswick
9.2
This is the second part of my technical review of the Sibeliusá7 öMusic
Processing Expert Systemò, the first part being in Archive 9.1 p51.
9.2
Designing a score
9.2
The layout of a musical score, just like any other document, has to be
planned in order to produce the desired result. With a DTP package, this
generally involves designing a ÉMaster Pageæ; the Sibelius equivalent is
creating the Éinstrumentsæ in the score.
9.2
As an example, I will describe the production of a simple score Ö
Mozartæs overture to öThe Marriage of Figaroò. Sample files illustrating
the process are on the Archive monthly disc. Unlike the ÉMoonlightæ file
provided last time, these files will load into the Sibeliusá7 Demo
Version (thanks to Ben Finn for the means to do this.)
9.2
ÉFigaroæ consists of eleven instruments: flute, oboe, clarinet, bassoon,
horn, trombone, timpani, violin, viola, cello and double bass. However,
there is a further decision required because most of these instruments
have more than one player, e.g. two flute parts, each with different
notes to play.
9.2
Players
9.2
Sibelius allows multiple players to be notated in two different ways,
which can either be used exclusively or mixed and matched. However, once
the decision has been taken, there is no easy way of switching between
the methods, so the implications of the choice need to be considered
before making the decision.
9.2
The traditional notation is for several players to share a single stave,
with numbers indicating which player(s) the notes are for. Sibelius
allows this by means of Éplayer textæ, and these numbers are
automatically shown at the beginning of each stave.
9.2
The alternative approach is to use a separate stave for each player
(although the player numbers may also be used at the start of the score
in order to give numbers at the start of each stave). The staves are
part of the same instrument in just the same way as the right and left
hand staves of piano music.
9.2
The two methods can be combined, by having several staves, each of which
has several players. It is possible for a player to switch between
staves, although this is extremely bad style! It is also conventional to
use two separate instruments for Violins I & II.
9.2
I initially decided to go for the first method, since this was how the
original score looked. This has the advantage that less staves are
needed, and hence the score is generally fewer pages. The drawbacks will
become apparent shortly!
9.2
Instruments
9.2
A considerable number of instruments are pre-defined in Sibelius,
although these can be varied if required. For example, Mozart would have
written his instruments in German (as shown above). Each instrument has
both a full name and an abbreviation, each of which can be edited
independently (e.g. ÉOboiæ and ÉOb.æ). The full names can be used at the
start of every stave, or more usually just at the start of the first
page.
9.2
If an instrument is required which is not on the standard list (e.g.
ÉHorn in Dæ), it is just a matter of picking another similar instrument
with the same transposition (e.g. ÉTrumpet in Dæ) and editing its name.
9.2
The pre-defined instruments will automatically appear in the correct
conventional order within the score, and will be bracketed together in
appropriate sections. Again, this default order and bracketing can be
overridden, but the order cannot be changed after the instruments have
been created.
9.2
Transposition
9.2
The transposition key of the instruments must be chosen with care: it is
no good initially choosing a ÉClarinet in B flatæ, and deciding later to
change it into a ÉClarinet in Aæ by changing its name! If you try,
Sibelius still thinks it is the original ÉClarinet in Aæ, and all the
transposition goes wrong.
9.2
[To explain the jargon: If a ÉCæ is played on a ÉClarinet in Aæ, it
sounds at the same pitch as an ÉAæ played on normal (non-transposing)
instrument. Normal instruments are therefore Éin Cæ.]
9.2
Sibelius allows the transposition to be handled in two different ways:
either the score is written as it will be played (Sibelius automatically
transposes all key signatures) and transposes appropriately during
playback, or the score is written as it will sound, and Sibelius
transposes the individual parts as they are extracted. The second method
allows the composer to ignore the transposition whilst he is creating,
leaving Sibelius to take care of it all later.
9.2
For example, ÉFigaroæ contains ÉClarinet in Aæ, hence the key signature
at the start of the stave is F major (one flat) whereas most instruments
are in D major (two sharps). Likewise the Horn and Trombone (which are
both Éin Dæ) have key signatures of C major (no sharps or flats).
However, even if we had been using a ÉHorn in Fæ, it would still have
appeared without any key signature, since it is conventional to show
some instruments with keys (e.g. Timpani). Sibelius allows this too!
9.2
Extraction
9.2
After all this palaver of setting up the framework of the score,
instruments, staves and all, the individual notes can be entered in just
the same way as for a simple piano score, by inserting, selecting and
copying notes. Once all the notes are completed (a non-trivial task, for
a score the size of ÉFigaroæ!), there are some very clever things that
Sibelius can do for you.
9.2
The full score is generally only used to allow the conductor to follow
the music played by everyone in the orchestra. What is required is a
separate piece of music for each member of the orchestra, containing
just their part and nothing else. This is really what Sibelius was
designed to do, and it does it remarkably well. At the click of the
mouse, the whole score is reformatted and replaced by just the part
which was requested. (It is therefore vitally important to save the work
just before extracting the part, æcos thereæs no going back! Sibelius
warns you if you havenæt saved.)
9.2
It is at this point that the main implication of having chosen to put
all players on a single stave becomes apparent. When, for example, the
flute part is extracted, it will contain the music for both FluteáI and
FluteáII. If that is what is required, all well and good, but if what
you wanted was two separate parts for the two flutes, youære in trouble!
The only way to produce this is to manually delete all the unwanted
notes, leaving just the notes for one player Ö this can involve
considerable time and effort.
9.2
The moral of the story is that you should use separate staves from the
outset if you intend extracting players individually. In fact, what I
chose to do was to save my completed score (file ÉFullScoreæ on the
monthly disc) and then modify it into a form in which I could extract
the players individually (file ÉExtractoræ on the disc). This process
involved creating additional staves for each instrument, copying the
music from the original stave onto the new stave, and deleting half the
notes on each stave. Although this process took me several hours, it was
worth the effort since I could print the full score as required (from
the original attempt) and extract parts individually from the extractor
version.
9.2
Even with the players on two separate staves, Sibelius currently only
allows both players to be extracted together. It is then relatively
simple (& quick) to delete the complete stave for the unwanted player.
The alpha-test of the latest version allows separate staves to be
extracted individually, thus simplifying matters even further.
9.2
The extracted parts may need a few tweaks by hand, and can then be saved
as separate files. Sibelius changes the filename for you, to prevent you
from overwriting your full score. I have enclosed a few examples of
extracted parts (files ÉClarinet1æ, ÉTimpaniæ and ÉViolin1æ).
9.2
Playback
9.2
At any time, Sibelius can give you a performance of your masterpiece.
This is possible through the internal speaker (although all instruments
sound like pianos!), but best results are obtained by using Midi
equipment.
9.2
Standard ÉGeneral Midiæ synthesizers are supported, as are a number of
specific sound modules (e.g. Proteus FX, and Roland SC¡88). However, it
is possible to tell Sibelius to use a specific sound (or Épatchæ) on
whatever equipment you have. I have both a Midi piano and an SC¡88, the
latter providing several hundred different instrument sounds, ranging
from standard orchestral instruments, ethnic instruments and weird sound
effects Ö you can even arrange for a round of applause to be produced at
the end of the performance if you need a virtual audience! Some of these
sound effects would be useful if you were producing a film sound-track.
9.2
The quality of the sound produced is really down to the quality of the
Midi equipment being used, since Sibelius merely sends messages down the
Midi to say when notes should be turned on and off. The SC¡88 produces
reasonably good all round orchestral instruments, although I would say
that the String sounds are less realistic than the woodwind and brass.
9.2
The main limitation of the playback is that not all symbols are actually
taken into account when playing the score. Most notable of these are
ornaments (grace notes, trills, turns, mordants etc), 8vaæs, tremolos,
arpeggiated-chords, repeat signs, etc. It is generally possible,
however, to produce a modified version of the score which is suitable
for playback. This involves explicitly spelling-out the shorthand
symbols with individual notes. This trill can be written as:
9.2

9.2
Likewise for tremolos:
9.2
Drum-rolls (e.g. Timpani bar 133) can be produced like this, and sound
even better if two notes are sounded together. [File ÉPlayerSæ includes
these modifications to allow correct playback]. I am assured that the
forthcoming Versioná3 will play most of the currently missing features
without requiring these modifications.
9.2
Sounds realistic?
9.2
One of the drawbacks of computer-generated music is that it tends to
sound too mechanical to be believed. Sibelius Software have gone to
great lengths to try and make their music sound as realistic as
possible. Two separate features contribute towards this: Espressivo and
Soundscaping.
9.2
The espressivo feature, as described last time, uses subtle changes in
volume to make the music sound less mechanical. However, even with this,
there is a tendency for many notes played together to sound like an
organ rather than an orchestra. There are two possible approaches to
this problem: the first is not to sound the notes at exactly the same
time Ö a real orchestra would have slight variations between the
musicians (this is not currently implemented). The second possibility is
to deceive the ears into believing that the sounds are coming from
different places, corresponding with the positions of the orchestra on
stage Ö soundscaping.
9.2
Three separate attributes of the sound can be used to create this
audible illusion: pan (stereo position), reverberation (echo) and
balance (relative loudness). Many modern Midi synthesizers allow these
attributes to be varied to good effect. The trick is working out the
correct values for each of these parameters Ö each instrument has to be
calculated individually. As a rough guide, the reverberation increases
with distance away from the listener (there is more echo at the back of
the stage!) and balance can be used to give an indication of the
relative strengths of each section of the orchestra. The diagram
illustrates my simulated orchestra:
9.2
There is one slight limitation to the soundscaping, imposed because of
Midi restrictions rather than by Sibelius. Reverb, Pan and Balance can
only be specified for each Midi channel, rather than for individual
notes. This means that when Sibelius plays several parts using the same
channel, the parameters are used for just one of the instruments. Since
there are only 16 Midi channels, you are restricted to 16 different
soundscape positions. Multiple Midi interfaces could be fitted to
increase this flexibility, although unfortunately this feature does not
currently work. (Many thanks to Roy at KCS for loaning me a second Midi
interface to try it out!) At present, the soundscape parameters are
specified by typing numbers into a menu, which is not particularly
intuitive. Maybe in the future it will be possible to drag the musicians
around a virtual stage?
9.2
[File ÉPlayerDæ has separate staves for each player. However, the SC-88
tends to produce an unpleasant sound (known as Éphasingæ) when the
players are in unison. This should be reduced when multiple Midi
interfaces work, since the players will be at slightly different
positions. The SC¡88 has two separate Midi inputs, thus allowing 32
separate soundscape positions.]
9.2
Performance issues
9.2
It cannot be denied that Sibeliusá7 is fast, both in terms of its
internal operation and its usability. It also has a remarkably quick
learning curve Ö my Moonlight Sonata score was finished within a
fortnight of first using Sibeliusá7 (and I only have chance to use it in
the evenings!). I can now transcribe music at an average rate of around
20-30 minutes per A4 page, depending on the complexity of the score.
9.2
Sibeliusá7 can also produce remarkably large scores, even on a
comparatively inexpensive machine. My largest project to date has been a
vocal score for a complete operetta Ö Gilbert and Sullivanæs
öTheáMikadoò. This file is only 610Kb long, yet it contains almost 3700
bars of music in its 300+ pages. This means that, even with such a large
file, Sibeliusá7 will run quite happily on a 2Mb A3010.
9.2
There are a few size limitations imposed by Sibeliusá7, but it is highly
unlikely that any composer would want to compose such a complex piece
(the main restrictions are 128 instruments max, and 128 staves per page
max). In the event of anybody requiring 128 staves per page, the page
size can be increased up to 999mm square!
9.2
The only significant problem I encountered whilst working on my monster
Mikado score was concerned with adding new bars into very large scores
(i.e. over 1000 bars), which is rather slow and occasionally generates a
ÉSelf Test Failedæ error. However, the nice thing about Sibeliusá7
errors is that when it gives you the choice to ÉContinueæ or ÉQuitæ, it
actually lets you continue, rather than simply generating another error
message (like some other programs I could mention). I can honestly say
that I havenæt yet had an error which Sibelius couldnæt recover from Ö
it just beeps and puts you back to the top of the previous page in the
score!
9.2
The future
9.2
Sibelius Software are constantly updating the package, both with bug
fixes and additions requested by their users. The package is used by
many leading composers as well as music publishing companies, and is
used in all corners of the globe (Sibelius claim to have users on every
continent except Antarctica!).
9.2
Version 3 is due to be released very soon, possibly even by the time you
read this, and this promises to be a significant step forward. Whilst
writing this article, I received a copy of an alpha-test version (2.51c)
which contains a few of the features to be released in versioná3,
including a scratch-pad (for musical Édoodlingæ whilst composing), an
editing screen with configurable degree of WYSIWYGæness, and support for
internationalisation. Versioná3 also promises to contain more user-
friendly alternatives to some of the currently cumbersome features of
the package (e.g. full playback without manual alteration of the score)
as well as real-time Midi input and Midi-file support.
9.2
Conclusion
9.2
Sibeliusá7 is very versatile package, allowing virtually any imaginable
type of music to be transcribed. Itæs high price tag is an indication of
the market at which the product is targeted (hence the inclusion of 24-
hour telephone support). It allows a composer to produce performance
quality printouts without the time and expense of having them
professionally produced.
9.2
A cut-down version (with a few built-in restrictions) is available at a
price more affordable to the hobbyist or school user.
9.2
This review was carried out on Sibeliusá7 version 2.50p running on a
RiscáPC.áuá
9.2
Apollonius PDT
9.2
Dave Wilcox
9.2
Oak Solutions have re-entered the draughting package area with the
release of their new Apollonius PDT package, (ÉParametric Design Toolæ).
I say re-entered because the name rang a bell from times gone by. After
a little digging, I found someone with a copy of the old Oak PDT package
for comparison purposes. Forget it; it took about two minutes to lose me
with the old package, amongst assorted menus and the like, and it was
single-tasking!! This new offering, I am pleased to say, is totally
opposite to this.
9.2
What do you get?
9.2
The software is presented in a rather large (A4) cardboard box
containing a 79-page spiral-bound A5 manual and two discs. Disc one
contains the main program and three libraries for storing paper designs,
hatching designs and frequently-used bits of drawings. Also, there are
two applications, called !DrawPrint and !DrawPlot, which are designed to
run alongside your usual printer driver and control the output,
including poster size output. Obviously, one is for usual printer
output, and the other for plotter output. Also included is a !Scrap
directory and a folder of five example drawings.
9.2
The second disc contains a familiar Oak package, !Projector, for the
display of animated images, !Snaphappy, an Ace film maker, and five
examples.
9.2
There is no copy protection on this package but you are required to
enter your name, which is recorded within the program and which is
displayed on the title screen when you run the program. For installation
onto hard disc, simply drag all files and directories to the desired
location.
9.2
What is Apollonius?
9.2
The best way to define the package is to quote Oakæs claim in their
opening page of their manual Ö öyou have an intelligent, simple-to-use
application which provides enormous productivity in generating clear and
useful technical drawings of mechanical parts and the relationships
between those partsò.
9.2
How do they fulfil this claim? On opening the worksheet it is quite
daunting Ö not because it is bulging with tools Ö quite the reverse.
There is only a small toolbox, as can be seen above, with eleven tools,
(well ten really, as the hatching tool is not implemented in this
version). From these ten tools, there are really only three main work
tools. Confession time Ö I now started to read the manual a little more
intently.
9.2
On opening a worksheet, you start with a blank sheet of paper with x and
y axes. The intelligence of this program now starts to work and, I have
to say, work well. Depending on what you click on, and where you move
the mouse in relation to other objects within your drawing, the program
decides what you want to draw. To give a couple of examples, with the
line tool selected, if you click on a line and then second click on a
circle, you obtain a parallel line which is tangential to the circle.
Then, if you click on a line and then second click on another line, you
obtain the bisector of the two lines. With the circle tool, if you click
on a point and then second click on a circle, you obtain a circle
tangent to the chosen circle, with its centre on the selected point. The
options go on and on, and are quite extensive, using just the three main
tools, line, circle and point. The appropriate combinations take a while
to learn but, with a little application and use, are fairly obvious.
9.2
For precise or repetitive measurements it is possible to define
variables, and then use these when needed in the drawing, e.g.
Fillet=5mm.
9.2
Also included is a style menu, like Impression, where you can predefine
line thickness, colour and pattern, or text colour, size, font and, when
implemented, the desired fill pattern. All that is then required is the
selection, from a menu, of the style you require. There is also an
effect option in the main menu but, as in Impression, you are better off
designing and using the style option, unless it really is a one-off
effect you are after.
9.2
Once your drawing structure is complete, you need to select the ink tool
and draw in the outline of your drawing, pretty much as you would on a
drawing board, as can again be seen in the diagram. Once you are
satisfied with your drawing, all construction lines may be turned off to
show your drawing in all its glory Ö see the inset above left.
9.2
The next tools in the bar are fairly self-explanatory so I will only
give a brief account of what they do. First is the text tool, which
allows you to label and comment your drawings. The only point to make
here is that text can be made to run horizontal, or parallel to a line,
or parallel to a circle. Next is the dimensioning tool. You are able to
dimension lengths, angles, radii and diameters by clicking on two or
three points, dependent upon the desired measurement. Once decided,
these measurements may be internally or externally displayed Ö again
this can be seen in the example diagram. The select tool is next in the
line and is used in a similar style to ÉSelectæ in Draw, or other
similar packages. The next two greyed-out icons are the mirror tool and
the multicopy tool. These act on selected items, and only become active
once something is selected.
9.2
Saving and printing
9.2
OK, so your drawing is complete Ö now what do you do with it? Firstly,
we have the four save options. You can save your drawing as either a
full Apollonius file, a drawfile, a text file or a DXF file (minus
parametric information). These options appear to cover most
eventualities. The next option is to print out a hard copy of your
drawing. There is no problem here, but you must have your usual printer/
plotter driver loaded and also load DrawPrint or DrawPlot, as mentioned
above.
9.2
It is now possible, using the advanced features of the software, i.e.
ÉSnaphappyæ, to combine different positions of each piece of your
drawing to make a film showing how the combination of pieces will
actually work together. I do not intend to go through this action step
by step, but suffice it to say that it can be done and you end up with
an ÉAce Filmæ, showing how the objects are linked and how they are
designed to move together. There is an example on this monthæs disc in
the form of an engine piston, connecting rod and crankshaft going
through a cycle.
9.2
Conclusion
9.2
Does this software fulfil the claims made by Oak? Yes, I believe it
does. You can learn how to use most of it quite quickly, although some
of the intricacies take a little longer, as would be expected. I know
this is a 2D drawing package, but I would have liked to see an ellipse
tool for use in 2D plans or isometric projections. Most packages seem to
lack this, perhaps because the programming required is too complex, but
thatæs someone elseæs domain, not mine. You can, however, resort to the
technical method shown below, if needs must.
9.2
Development work is obviously continuing, because tools are displayed
which are not yet functional Ö all credit to Oak. I feel they could have
released the package minus the troublesome sectors, or worse, with them
for the customer to beta-test for them.
9.2
This package has, I feel, fulfilled the claims of its producers and, as
such, I feel is good value for money. Apollonius PDT costs ú150 +VAT
from Oak Solutions Ltd, or ú165 through Archive. If you own WorraCAD or
Oak PDT, you can upgrade via Oak for ú75 +VAT.áuá
9.2
Apollonius
9.2
A second view
9.2
Brian Cowan
9.2
I purchased Apollonius as an upgrade from WorraCAD. As with many
software purchases, you donæt really know how useful the thing will be
until you have used it. I expected to use the package for computer-aided
design (CAD), with the parametric aspect enabling me to change parts of
the design as part of a öwhat ifò development exercise. So far, I have
used Apollonius for two real-life applications: one trivial and the
other serious.
9.2
First application
9.2
In the trivial application, I had to drill a number of holes in a board
to mount a large pressure gauge. The hole locations were specified as
being equally spaced on a given pitch circle diameter (PCD). What I
wanted, to enable me to drill the holes, was the x and y coordinates of
each hole. I was able to draw the layout of the holes in Apollonius
according to the given specification with ease Ö well, relative ease!
Then, using the automatic dimensioning facility of Apollonius, it was a
simple task to display the coordinates of the holes as distances from a
horizontal and a vertical datum.
9.2
Second application
9.2
Fresh from the success of this exercise, I decided to embark on the
design of a (relatively) complex item required in my laboratory.
Conventionally, this would have been designed on paper and I decided to
test Apollonius in this real-life application. This was a complex
object, to be machined out of copper. The final Apollonius drawing is
shown overleaf.
9.2
The first problem was that the program would frequently crash. This
encouraged me to make frequent back ups Ö not a bad thing, anyway.
Unfortunately though, the crashes tended to hang the whole computer. As
the drawing developed, the next problem became apparent. The screen
refresh became unbearably slow. A little investigation showed that the
main program is written in Basic, although there are a number of
supporting relocatable modules. Now this is indeed a tribute to Acornæs
Basic coding, but I am surprised that a program of such complexity and
graphics speed requirements is not written in a compiled language, or
even hand-coded. Furthermore, Oak sells a Basic compiler, but they did
not even use that! The drawing shows the stage at which my patience ran
out and I stopped using Apollonius and continued annotating the drawing
by hand.
9.2
Confusing construction lines
9.2
After a while, as the drawing becomes more complex, the screen is
covered with construction lines which makes the appearance terribly
confusing. There is an option to hide all construction lines (as in the
figure shown) but I would suggest an option whereby only the
construction lines in the vicinity of the current working point, or
perhaps those selected by the user, are displayed.
9.2
Conclusion
9.2
My conclusion is that this is a brilliant program Ö or at least it has
the potential to be so. The Éspartan simplicityæ of the user interface
is quite superb. All the right ideas are there, but the present
implementation (my version is 0.95) is rather incomplete and can hardly
be regarded as more than a beta test version. Certainly, at the moment,
this is not what you would expect from a ú150 product, but assuming Oak
continues to develop it and the speed is enhanced by using a compiler of
some sort then it could be a great success.áuá
9.2