Archive Magazine 1997/ARCHIVE_97.iso/text/hints/vol_06/issue04

Text File | 1995-02-16 | 26KB | 541 lines

Hints and Tips
6.4
Å   Refilling BJ300/330 Ink Cartridges Ö The cartridges have a ösoak upò
pad in them as well as the ink sachet so if the pad is black and full of
waste ink you canæt refill them! or can you? This is how to do it.
6.4
Split the cartridge along the seam and lift off the top. It is only
lightly tacked together so its quite easy to prise apart.
6.4
(The next bit is messy so use disposable gloves so you do not get ink
over your hands.)
6.4
Lift out the ink sachet (keep it the same way up) and then the pad and
wipe clean the cartridge. Dispose of the pad in a plastic bag, trying
not to get too messy.
6.4
I used kitchen roll for the new pad. Cut about 12 pieces to the size and
shape of the pad then place in the cartridge, now place the sachet on
top. Keep it the same way round to make sure the needle hole lines up
with the needle in the printer.
6.4
Thatæs what the safety flap is for that drops down when you remove the
cartridge so you donæt jab yourself.
6.4
Replace the top of the cartridge, securing it with just a couple of
drops of glue so it can be removed again, it is now ready to be filled.
6.4
I took the advice of Stuart Bell (Archive 4.5 page 7) and used Quink
Permanent Black @ ú1.70p for 54ml. The sachet takes 40ml, so donæt over-
fill it. Obtain a 20ml syringe and 21 gauge needle from your chemist. (A
20ml syringe is about the best as larger ones tend to be very
expensive.)
6.4
Carefully fill the sachet making sure the needle goes in the same hole.
If you make another hole, air can get in and cause problems.
6.4
Donæt forget to wash out the syringe and needle afterwards.
6.4
So, at the cost of approx ú1.70p plus the syringe and a few sheets of
kitchen roll, you now have a refilled ink cartridge which would normally
cost about ú10 to refill and between ú15 Ö ú20 for a new one.
6.4
If any of you wonder what the soak up pad is for, when the printer is
switched on, ink is jettisoned through the nozzles to clean them and
this then runs down into the cartridge.
6.4
Å   D-type connector problems Ö In Archive 4.8 p7, there was a tip about
taking the washers from under the hexagonal pillars of the D-type
connectors. I think it is worth re-stating it for those readers who
missed it. My A310 was in a Énot workingæ state the other day Ö it
refused to produce any green. I checked that the two screws holding the
D-plug into the socket were tight and checked out the monitor and lead
which worked fine, but still no green. A few days later, I remembered
the tip, removed the washers and the green returned.á Les May,
Rochdale

Using RISC-OSá3
6.4
Hugh Eagle
6.4
I hope that all who have ordered RISC-OSá3 upgrades will have received
them by the time this issue is published and that those who have been
waiting to make up their minds about upgrading will have been suffi
ciently encouraged by now to go ahead. There will be considerable
advantages to all Archimedes users if we all use the same operating
system: above all programmers will be able to use the new improved
features without having to worry about backwards compatibility.
Inevitably, this column will tend to contain quite a lot of negative
material about difficulties that some people have had, but it is
important to appreciate that most upgraders have had very little real
trouble (some inconvenience, perhaps, but not insuperable problems).
There are genuine advantages in RISC-OSá3, most programs work well and I
believe that most users are pleased with it.
6.4
The deadlines for the December and January editions of Archive have been
concertinaæd close together (because of Christmas, etc) so there has
been no time for any reactions to the first RISC-OSá3 column. However,
contributions have continued to arrive in response to the original
request ù several more problems, criticisms, etc but also some interest
ing hints & tips.
6.4
Please send anything that you think may be relevant either to Archive or
to me, Hugh Eagle at 48áSmithbarn, Horsham, Sussex  RH13á6DX.
6.4
Fitting the chips to an A310
6.4
The upgrade to my A310 with an IFEL carrier board was quite straightfor
ward, with the help of good instructions. IFEL recommend that you remove
the motherboard, as a fairly good pressure is required to insert the
carrier board. I encountered no problems but the soldering of three
wires from the carrier board on to the legs of a chip, is not for the
faint hearted. (Memories of my Beeb days came flooding back). (Roger
Power.)
6.4
Configuring for a SCSI hard drive
6.4
The configure application is OK apart from the settings appertaining to
my Oak SCSI filing system. I have overcome this by a separate !Config
Obey file that I run as well as Configure and which reads as follows:
6.4
*configure drive 4
6.4
*configure filesystem SCSI
6.4
*SCSI
6.4
*configure SCSIDrive 4
6.4
*OPT 4,2
6.4
This is obviously only needed after a factory reset which shouldnæt be
very often. Unfortunately, at the moment it is, as further problems have
now occurred. Namely my Impression doesnæt read the Dongle all the time
and appears to require a factory reset. This is only since the arrival
of RISC-OS 3.1 and I have yet to find out whether or not the Dongle (or
maybe even RISC-OS 3.1) is at fault. Obviously I have checked all the
connections over and over again. (Roger Power.)
6.4
(Roger, I suspect itæs more likely to be a hardware problem on the
p.c.b. after fitting the I.F.E.L. ROM upgrade in your A310. There are no
problems, that we know of, with dongles. Ed.)
6.4
5╝ö floppy drive
6.4
My external 5╝ö floppy drive is too slow for my Archimedes, with the
result of the heads chattering alarmingly. I had previously got round
this problem with the command *Configure STEP 3 6. However, RISC-OS 3.1
does not appear to accept this, only STEP 3 3. Can anyone help, please?
(Roger Power.)
6.4
LaserDirect printer driver
6.4
(Incidentally, Computer Concepts have told me that öRISC-OSá3 compatible
printer drivers should be available around the middle of next year. This
will cover TurboDrivers, FaxPack and LaserDirectò HE)
6.4
In RISC-OS 2, I solved the problems of using a LaserDirect printer on a
machine to which a parallel printer is also attached, by including a
simple driver in an application which resides on the iconbar and does
lots of idiosyncratic things which suit my personal use of the machine.
The driver stores data dragged to it in a buffer and outputs it to the
dot-matrix line by line on each Wimp_Poll with reason code 0. This
enables me to leave the LaserDirect on the iconbar. If I want to print
some text or Basic, the data is dragged with <shift> held down,
otherwise the data is presumed to represent an address, which is
formatted for the 9-line labels with which, by default, the printer is
loaded. This is very handy, because I can drag the address directly out
of a DeskEdit or Impression window. My beef is that my routine orig
inally tested for a connected printer, thus:
6.4
DEFPROCChPr:*FX5,1
6.4
VDU2,1,0,3
6.4
SYSöOS_Byteò,152,3 TO ;f%: f%=f%AND2
6.4
IFf%=0SYSöOS_Byteò,145,3
6.4
*FX5,5
6.4
ENDPROC
6.4
Thus, if the 0 byte inserted into the printer buffer is still there, the
printer is not on and the data are output to screen via a command
window; otherwise, they go to the printer; f% being the determining
flag. Now, I can understand that it is an enhancement to RISC-OS to wait
if the printer is off, but I find it is wholly unacceptable that the
machine is locked up by so simple an event. The OS_Byte no longer works,
since presumably the machine is stuck at the end of line 3200! Now, the
RISC-OS driver is not stopped by such an event, but multitasks happily
waiting for the printer to be switched on. Clearly some routine is
available to deal with the situation; why could the release documenta
tion not give a clue?
6.4
I have had to abandon the routine temporarily because, if I wished to
display a file on screen, the printer was incidentally tested first.
This is no longer possible, unless I validate <escape> with *FX229
before calling the routine and reset on exit; this means exiting via the
error handler, however, and is one of the more difficult parts of Wimp
programming, I find! Any suggestions? (Mick Day.)
6.4
LaserDirect and ROM fonts
6.4
As mentioned last month, the current version of the Computer Conceptsæ
LaserDirect printer drivers are not fully RISC-OS 3 compatible. Thus
they will not cope with the extra features of Draw such as rotated text
or sprites. Furthermore, they will not find all of the fonts in the ROM-
based resources filing system. In particular, the italic versions of
both Homerton and Corpus are not seen. It is necessary to have the old
copies of the Homerton and Corpus fonts installed in the disc !Fonts
directory. (Brian Cowan.)
6.4
(I find that if I try to print these fonts from Impression, it refuses
to print but does allow me to carry on, whereas Draw locks up the
machine. If this is a printer driver problem it makes Computer Conceptsæ
apparent lack of interest in bringing out new drivers all the more
frustrating. If they do appear in öthe middle of next yearò that will be
about 20 months after the original release of RISC-OSá3! HE)
6.4
Dot matrix printers: formfeeds
6.4
I have yet to find a way of stopping the RISC-OS dot-matrix printer
driver from issuing a concluding formfeed when a short piece of text is
dropped on the icon and printed. I prefer to control such things myself;
any ideas? or am I, after all, an idiot? (Mick Day.)
6.4
DFS discs: donæt try öfreeò space
6.4
Put a DFS disc in drive 0 and click; the error window tells you it is an
unrecognised format. However, if you put a DFS disc in drive 0 and click
on ÉFreeæ you will crash the machine with ÉFile core in useæ rearing its
ugly head! Couldnæt the existing disc checking routines have been
invoked before plunging into the ÉFreeæ sequence? (Mick Day.)
6.4
Naming the RAM disc
6.4
RISC-OS 2 used RAM:$ as the prefix on the RAMdisc filer window and
Filer_OpenDir worked with it quite happily. However, you had to find out
by trial and error what discname to use in order to get sense out of,
e.g.
6.4
SYS öRamFS_FreeSpaceò,öRamDisc0ò TO room% : IFroom%>X% room%=0 : ENDPROC
6.4
Acorn could have detailed this irritating time-waster somewhere (like
the PRM). Now, I appreciate that RAM::RamDisc0.$ is generically the
correct format to use in the Acorn file system protocols and clicking on
the icon in RISC-OS 3 opens a window with that title. For backwards
compatibility, *Filer_OpenDir RAM:$ still works; jolly good. However, if
your software issues the command and you have already opened a window,
RAM::RamDisc0.$, from the iconbar, you get a second window identical in
all save the title, RAM:$! (Mick Day.)
6.4
Operating system version
6.4
The PRM tells us that SYSöXOS_Byteò,0,0 prints the version string: so it
does. However, SYSöOS_Byteò,0,1 TO ,A is supposed to return the OS
version number in A but it does not seem to do so. RISC-OS 2 and RISC-OS
3 on my machines both return 6 (the SYS number for OS_Byte)! However,
SYSöXOS_Byteò,0,0 TO A does return, in (A+4), the address of the version
string, so it can be extracted in the time-honoured manner. (Mick Day.)
6.4
MS-DOS: file extensions and formatting
6.4
The MultiFS utility is not required in RISC-OS 3; DOS discs and DOS
partitions on hard discs may be read directly with the new operating
system. I think that what Acorn have done is to integrate MultiFS into
the machineæs filers as an Image filing system. However, I cannot obtain
all the old facilities of MultiFS. In particular, it is not clear
whether the hierarchical method of dealing with file extensions can be
used; this was particularly useful. Also, I see that you can copy the
boot sectors from one DOS disc to another from the command line using
*CopyBoot, but I donæt know if this can be done from the desktop as an
option while formatting. Does anyone know? (Brian Cowan.)
6.4
Compression
6.4
CC have told me that there is a bug in version 1.10 of Compression which
can cause a corruption if a file is dragged between a CFS window and the
corresponding uncompressed filer window. If this is not done, Compres
sion should work OK. (Brian Cowan.) (See also the comment by Jochen
Konietzko in last monthæs column.)
6.4
Wish list for RISC-OSá4 (R. W. Darlington)
6.4
Å   When I use Name Disc from desktop, I want to see it display the
present disc name in the writable icon. (With my setup it does display
the name of the hard disc but not that of a floppy! HE)
6.4
Å   When I copy across a group of files from one directory to another, I
want to see the Filer check that there is sufficient disc space for the
copied files to fit before it starts to copy them. (Also, in the case of
D format discs, that the disc wonæt need compacting.)
6.4
Å   I want to see it copy a group of files from one disc to another a
little more intelligently than it does at the moment. I wish to see it
write all the directory information in one go, then write all the files,
instead of continually moving the heads across the surface of the disc
for each little file it writes to disc, which takes it an age!
6.4
Å   When I Set Type from Desktop, I want to see a list of possible
options, along with their icons, like !SetType by Emmet Spier.
6.4
Å   In !Edit, I want to see an option to ÉSelect Allæ.
6.4
Å   In !SciCalc, which uses BASIC64, I want to see it display figures to
the full precision of the Basic, 18 significant figures or so and not
the 10 displayed at present. Also, I want to see it display exponents
like this ö╫1018ò and NOT öE18ò. I also want to see an option to select
engineering or scientific notation.
6.4
Å   When deleting columns at the far right hand edge of a sprite, it
deletes too many columns.
6.4
Å   If I save a sprite (using !Paint) of just one pixel in height (any
length?) and colour it a different colour than desktop grey, then when I
use this sprite to create a backdrop using the !Pinboard, not only does
it take an incredible amount of time to draw the backdrop, it also uses
the wrong colour. It comes out in desktop grey! Is this a problem with
!Paint or !Pinboard? (Or is the user making unreasonable demands? HE)
6.4
Å   In the Set Copy Options, I want to see an option whereby it can be
made to ask for confirmation only if a deletion is being made, rather
than just an access request or a copy command.
6.4
Å   Now that some fonts are inside RISC-OSá3 itself, I want to see a
configure option to set the desktop default font to other than the
system font.
6.4
Å   I also want to see a new MODE equivalent to MODE 31 in every way
except that the pixel units are set such that all icons and everything
on screen appears half the size. Or, do the same for MODEs 18, 19, 20,
and 21.
6.4
Å   When I insert a disc with a foreign format, e.g. an IBM formatted
disc, into the drives, I want to see a little more obviously that it is
a foreign format. Why not have the window header in a different colour,
e.g. red! Or do it some other way if you must, but make it immediately
obvious that it is not a native format disc.
6.4
Å   When a window now goes off screen and the bottom right-hand Ésizeæ
control is grabbed, the window increases in size upwards when it should
not. (Isnæt this one of the intended improvements in RISC-OSá3? HE)
6.4
Pinboard backdrop sprites
6.4
R. W. Darlington has also sent in a collection of 74 sprites suitable
for tiling the backdrop, a voice module (which sounds to me as if it
might have been generated not a billion light years from the Sirius
Cybernetics Corporation) and some suggested modifications to the !Boot
file which will sound the voice module and display a different backdrop
each time the computer is re-booted.
6.4
The modifications to the !Boot file read as follows:
6.4
RMEnsure PinVoice 0 RMLoad PinVoice
6.4
CHANNELVOICE 1 10
6.4
SOUND 1 &FFF1 60 160
6.4
WimpMode 31 :REM to suite my sprites
6.4
Run ADFS::HD4.$.PinSp.RenSprites
6.4
Pinboard
6.4
Backdrop -T ADFS::HD4.$.PinSp .Sprit01
6.4
This assumes that the PinSp directory contains the backdrop sprites and
an Obey file called RenSprites which simply cycles the sprite names and
reads as follows:
6.4
Rename ADFS::HD4.$.PinSp.Sprit01 ADFS::HD4.$.PinSp.Sprit00
6.4
Rename ADFS::HD4.$.PinSp.Sprit02 ADFS::HD4.$.PinSp.Sprit01
6.4
......
6.4
Rename ADFS::HD4.$.PinSp.Sprit00 ADFS::HD4.$.PinSp.Sprit74
6.4
Screen blanker configuration
6.4
Does anyone know which *configuration command sets the blank out time,
or where this appears in the *Status data. I can set it using Acorns
!Configure program in the Apps directory, but cannot find it elsewhere
for use by a star command. (Roger Darlington.)
6.4
*Filer_Run syntax
6.4
My tip last month about using *Filer_Run with a variable application
name was unnecessarily convoluted. Although *Filer_Run <App$Dir> doesnæt
work, *Filer_Run <App$Dir>.!Run does.
6.4
Fitting RISC-OS 3.1 to Computerware/Avie/Atomwide RAM upgrades
6.4
The new RISC-OS ROMs are easily fitted into the four sockets provided on
the main RAM board. The ROMs should be fitted as described in the
instructions supplied with the RISC-OS upgrade.
6.4
Locate the two links on the RAM board and swap the jumper to position B
for both.
6.4
Locate LK12 on the main PCB, this is just under the RAM PCB where the
cable enters from the left. There should be two links placed in the
east-west postion. Remove these links and replace them in the north-
south position.
6.4
LK12 is not always fitted and exists as a pair of PCB tracks on the
topside of the main PCB. These can be cut using a small sharp knife. The
new links can then be made on the underside of the PCB using tinned
copper wire and a soldering iron Ö as shown below.
6.4
A310 Issue 1 PCBæs do not have LK12 fitted at all and require more
difficult modification. Please contact Avie for assistance.
6.4
The fitting of RISC-OS 3 will be performed by Avie for ú6.50 + VAT Ö
this charge is simply to cover return carriage.ááA
6.4
Å   ABC Compiler Ö Iæve followed the discussions in Archive about the
relative merits of the RiscBasic and ABC compilers with interest
(Archive 6.1 p49). I donæt feel that there is much weight to the
argument that ABC is compiling a language different from Basic V. The
differences are quite small. The evening I received the ABC package, I
got a program of over a thousand lines running with the compiler in
about an hour which included writing some code to initialise several
arrays and removing some redundant code. When I write programs under the
Basic V interpreter, I just take the differences into account.
6.4
My major grumble is that even when I bought the ABC package a year ago,
it had a minor bug which shows itself sometimes when the object code
icon is dragged to a directory Ö it requires the machine to be reini
tialised. An upgrade to the latest version, which presumably will have
corrected this bug, will cost me ú40, which I think is a bit steep if
itæs only the bug fix that is any help to me.á Les May, Rochdale
6.4
Å   EasiWord 2 up(?)grade Ö I did have version 1.07 of Minervaæs EasiWord
and, after seeing the adverts for the WYSIWYG version, EasiWord2, I
decided to go for the upgrade.
6.4
Now, I do not know anything about 1st Word Plus, so the fact that
EasiWord2 was similar conveyed nothing to me. However, when I tried this
new version, I was niggled to find that I couldnæt print without a RISC-
OS printer driver being installed.
6.4
What was much worse was the fact that I could no longer send control
codes to my printer! Horror of horrors Ö I had lost the ability to print
in double height and in a choice of seven colours on my old Epson
LQ2500+. Let readers be warned!
6.4
I wrote to Minerva and expressed my dismay about their new package. They
very kindly invited me to return version 2 for a refund or part
exchange. I took up their offer and they even gave me a new package of
their old EasiWord 1.07. Well done, Minerva!
6.4
So, before you upgrade, be sure that it actually is an UPgrade for your
purposes.á Keith Lowe, Pickering
6.4
Å   Scheme Ö If Sue Lawley asks me which book I want to take to a desert
island, without hesitation I will have to say ÉStructure and Interpreta
tion of Computer Programsæ by Abelson and Sussman. I reckon that after a
few years of studying it without any distractions, I would know how to
set about programming a computer. The language used by these authors is
Scheme, a stripped down, elegant and refined version of Lisp.
6.4
If you think Lisp is just an acronym for ÉLots of Irritating Single
Parenthesesæ, think again. With even a simple parentheses-matching text
editor as supplied with EdScheme, that bogey disappears and you quickly
come to realise that the apparently strange syntax of Lisp-like
languages such as Scheme is in fact a very consistent and clear way of
expressing a computer program. Indeed, just as we in Britain are used to
seeing a Pascal-like pseudo-code used to express a fragment of code, US
books aimed at the academic community often use Lisp for the same
purpose.
6.4
I had read about the first third of the Abelson book before taking the
plunge and buying EdScheme. What arrived was the Scheme optimising
incremental compiler and associated editor on a single disc, a thinnish,
100 pages plus, User Guide and Reference Manual, and a thick, 300 pages
plus, Schemeræs Guide. This package is, in fact, a complete programming
course at a total cost of ú60 plus p&p.
6.4
The guide is aimed rather firmly at the late secondary school market and
starts with a deceptively simple approach to programming by asking the
programmer to construct pencil and paper machines capable of performing
given tasks. Even when programming has been introduced, the guide
continues to use the Émachineæ diagrams alongside the Scheme code.
6.4
This approach has much to commend it. We are familiar with the idea of a
machine which carries out some operation on the raw materials fed into
it. Cans of beans are constructed from a supply of beans and empty cans.
The filled cans are transported as a package but, to make use of them,
we need another machine, a can opener, to open the package and get at
the contents. Much of Scheme programming is concerned with building the
machines to construct packages of data, machines to check their contents
and machines to open up the packages and make use of the contents.
6.4
One quickly comes to realise that within those intimidating parentheses
is the name of a machine which carries out some operation and the names
of items upon which it operates. That applies to arithmetic operations
too, so the label for the operation comes before the operands, so called
Polish or pre-fix notation.
6.4
By chapter 3, you are being asked to write an interpreter to add
fractions (try that in Basic!) and have been introduced to the concepts
of data abstraction and recursion. On the way, you have visited some
slightly eccentric ways of representing numbers in Lisp which, though
really of historical interest only, do force you to sharpen up your
programming skills. Gradually, a mental tool box is built up containing
procedures for selecting, removing, counting, substituting and reversing
elements in lists. The inner workings of the interpreter, ÉThe Scheme
Machineæ, are explained in chapter 5.
6.4
The machine analogy is explored further in chapter 6 and the problems of
handling infinitely large objects in chapter 7. As a finale, a game is
developed in the last chapter which embraces topics like artificial
intelligence and object-oriented programming.
6.4
Scheme seems to me to be one of the best kept secrets of the computing
world. This implementation is inexpensive and, though not multitasking,
can be entered from the desktop and cleanly exits back to it. It is
hoped that a RISC-OS compliant version will be released during 1993
though the cost will be slightly higher. This will enable Scheme to run
at the same time as other applications and allow code to be dragged into
a Scheme window and compiled. At present, there do not seem to be any
plans for a version which enables the user to create, close or resize
windows from Scheme, though the Macintosh version allows this to be
done.
6.4
I have learned a lot from my experiences with Scheme. Even when
programming in Basic, it has forced me to ask questions like, ÉIf I
store data in this way, how much of the code which accesses this data
will I have to rewrite if I decide I want to store my data in a
different way?æ My appreciation of the virtues of a highly consistent
syntax, with few exceptions, has made me more critical of other
languages to which I have access. It has also made me realise just how
much code I have to write which has nothing to do with expressing how I
want the data to be operated on (my model) but is necessary just to tell
the machine how to do it. I think Iæm a better programmer for having
taken the time to study Scheme.
6.4
It has also left me with a profound sense of despair. When I was
involved in education, I consoled myself with the notion that, for all
its faults, the A level system produced students who were much better
educated than a High School student in the USA, where the EdScheme
package has its origins. Yet Scheme seems to have made a negligible
impact in this country, probably because those who control education
believe that so long as we can produce GKOs (pronounced Geckos) Ö
Glorified Keyboard Operators Ö everything will be all right. With that
in mind, the decision has been taken to ignore the discipline of
programming and concentrate on IT Ö whatever that is. I think we are
making a big mistake.
6.4
EDScheme is available from Lambda Publications at a cost of ú60 plus
ú2.50 p&p. A 300 page copyable Resources Pack and a Teacheræs Guide is
also available at additional cost.
6.4
 Les May, Rochdale.ááA
6.4