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بt$`~t6t$PvWt$PvWƨt3$"t$t$ ƨt$PvW9&t~t9&>zu$PvW$PvW$PvWw$PvWh9&>ju9&X&&$ډFVRP9&69&6$PP%Pvv vvvW%PvW9&6&69&6&6:&6&6#%Pvv vvvWB:&6&6:&6&6:&6&60%Pvv vvvW=%PvWD:&&&(0T|RPE%Pvv vvvW vW" 9&$PP] FpP FVv~vvO%PvV vV" PvVj! FPQ\%QJ] PvV" PvVJ] PvvvJ] F~~;~v^^؋NJ*3QNJ*&3ZF;v|։~v] v_%PvV PvV" PvVJ] FF=vP FVvv`  t 2PP]  :&uvv`  t|] u t 3P( -*ui%PvV vV2 ui6`#6^#vVF  uN6p#6n#vvF  t~9&X&&e%PFPW ƋFv2PP] 9&X&&V\2PP]  :&u9&X&&ˎ9&X&&k%PFPV NjFvW 3^_]U WVFdžPƆ{dž8o%:dždž@~%BdžD%FdžH%J+NL9& & vx~prt89 +&G&n9&9ptH9&9vt=PP9&6&6`%P9&6&6ZT %P| T :&P FVpP FV+FF{{<vv~uZ6`#6^#%P~V P~V" P~VJ] ) ---------------------------------------------------------------------------- Q2) What version of module X can I assume that all users have? Currently the version numbers are :- Clib v3.75 Colours v0.52 FPEmulator v2.80 IRQUtils v0.12 Hourglass v2.02 Sound v1.13 WimpUtils v0.04 All of these modules are only needed if you intend running your applications on RISC OS 2 machines. The functionality of all these module versions have been incorporated into ROM under RISC OS 3. ---------------------------------------------------------------------------- Q3) What's the minimum version of module X that my program needs? What features were introduced/what bugs were fixed in which versions? These details will come with the release notes accompanying the module and the particular program, if properly done, will inform you of which versions of the module you need as required. ---------------------------------------------------------------------------- Q4) When using DOS discs I often find the last parts of files haven't been written correctly, what am I doing wrong? Under RISC OS 3 DOS, and indeed with any other ImageFS filing system, discs are treated as one large file and ADFS applies write-behind caching to nearly everything it does. (See the question on ADFSBuffers for more details about this.) This means while working on a DOS disc the entire disc is treated as one large open file. However as long as a file is held {binaries,sources}.acorn recently? Q6) What archives/FTP sites are available? Q7) How can I protect against viruses? Q8) Where can I obtain !Killer? Q9) What is a VIDC enhancer? Will I need one for my new multisync monitor? Q10) What are the main new features of RISC OS 3? Q11) How do I enable solid drags in RISC OS 3? Q12) What kind of Acorn machines are there? Q13) What are the memory limits of the Acorn machines? Q14) What is a second processor and what second processors are there? Q15) Are there any cards for IBM PC or compatable machines that Acorn have produced? Q16) What configuration of serial cable should I use on my Arc for modem work? Q17) Can PC VGA Monitors be added to an Archimedes? Q18) What is ADFSBuffers and what is the best setting for it? Q19) What is the current File-type allocation ranges and why won't Acorn provide a full file-type list? Q20) My disc gives me a 'Broken Directory' or my Free Space Map is corrupt, what can I do? Q21) My hard drive gives me disc errors when I use, what do the error numbers mean? Q22) What does the power on self-test check and how does it signal errors back to you? Q23) Is there a Modula 2 compiler for the Arc? Q24) Is Virtual Memory possible under RISC OS? Q25) How compatible with other systems is an Archimedes? Q26) What Acorn related companies are available on the net via email? ---------------------------------------------------------------------------- Q1) I have obtained [PD] program X but find it needs [version Y.YY of] module Z, which I don't have. Where can I get it? All patch modules and current versions of Clib and its ilk are sited on the NZ info-server and can be obtained from there if you are sited in NZ. Ideally your dealer will also have copies of them too and you should be able to obtain them from them. (If they don't you may like to pass on the ones from the info-server if you request them, so that they are up to-date.--3 | | 3---TxD------------------------TxD----2 | +---4---DTR------------------------DTR---20 | | 5---0v-------------------------SG-----7 | | 6---DSR------------------------CTS----5 | | 7---RTS------------------------RTS----4 | +---8---CTS 9---RI-------------------------DCD----8 Of course you can connect the Modem pin 20 to any one of pins 1, 4, or 8 on the Archimedes plug, as they are all connected together anyway. Chocks Away Extra Missions (the flight simulator from 4th Dimension) suggests that the serial cable be wired as above except that pins 1-4-6 are connected together and the modem's CTS (pin 5) be connected to the Arc's pin 8 (ie the connections at pins 6 and 8 be swapped over at the Arc's end). This has been and it also seems to work fine. However newer Arc's like the A5000 have come out (and indeed the occasional A310) with a `corrected` serial port. This newer serial port operates as it should and is directly compatible with standard PC cables. Most comms software about at the moment does not take this in account and assumes that you have a cable patched in the manner described above. If you do not use such a patched cable on these `fixed` serial ports the software will generally fail to work. ---------------------------------------------------------------------------- Q17) Can PC VGA Monitors be added to an Archimedes? It depends on what monitor you have, and what Archimedes you have. There are two main types of PC VGA monitors out there... 1) Fixed Frequency These monitors will only display video signals with certain line and refresh rates. They will typically only display CGA / EGA / VGA modes. 2) Multi Frequency These monitors will display any video signal within a certain range, typically 30-50Khz line rate and 50-80Hz refresh rate. Type 1 almost always require seperate syncs as the monitor uses the polarity of the syncs (mainly positive going negative or mainly negative going positive) to determine what the line and refresh rate should be. Type 2 vary. Some require seperate syncs (vertical and horizontal) and others will work with composite syncs (vertical and horizontal EOR together). As PC monitors typically start at a line rate of 30Khz compared to the TV broadcast modes (mode 12 etc.) that have a line rate of 15Khz, VIDC has to do more work to obtain a 30Khz line rate. This means that you computer will slow down silghtly if you use a 30Khz+ line rate monitor. If you have an ARM 3 fitted such slow downs will probably be negligable. Now, depending on what type of Archimedes you have depends on what type of monitor you can use. A540 / A5000 / A4 / A3010 / A3020 /A4000 Has software control over the polarity of the syncs and what frequency VIDC is clocked at. The A540 with RISC OS 2 can only use modes 26-28 (640x480) and 31 (800x600). However, by changing links and a *configure option, you can get the computer to generate seperate syncs with no problem. The other machines with RISC OS 3 can do even better. If you tell the computer that you have a VGA monitor it will re-map all of the 15Khz line rate modes up to 30KHz line rate. This means that you can play your games that require mode 12 / 13. However, as a PC monitor is designed to display 320 lines minimum then you will get a 'letterbox' effect as mode 12 has only 256 lines. All these machines have 24Mhz, 25.175Mhz and 36Mhz crystals to drive VIDC with. The 25.175Mhz crystal is needed to obtain the correct video rates for PC monitors displaying 640x480 screens. The 36Mhz crystal is used to obtain higher resolution modes, like 800x600x16 colours. A3000 This can generate seperate syncs but requires links to be set to determine the polarity. It has only a 24Mhz crystal and can therefore only drive 'forgiving' monitors correctly that don't mind the 640x480 video mode timings being slightly incorect. In order to obtain proper timings, and software control of the sync polarity, you will need a VGA VIDC Enhancer for the A3000. A400 series. The situation gets more complex. Due to an 'error' in the PCB / circuit diagram, the A400 series cannot generate seperate syncs satisfactorly. The video signal loses the green component when seperate syncs is selected. As standard, there is no polarity control over the syncs. In common with the A3000, there is only a 24Mhz crystal. If the PC monitor can handle composite syncs then the monitor can be used in 640x480 mode only. A300 series. Most, if not all, of the A300 series had the circuit board hardwired into composite mode continously. There is only a 24Mhz crystal, and only composite PC VGA monitors can be used. Conclusion: Apart from the A5000 and newer machines, no computer as standard can drive either a fixed frequency or multi-frequency PC monitor in all of the Archimedes modes satisfactorily. However VIDC enhancer boards can be bought to upgrade an Archimedes to handle the needed timing and signals. ---------------------------------------------------------------------------- Q18) What is ADFSBuffers and what is the best setting for it? ADFSBuffers are Read Ahead and Write Behind buffers for ADFS on your Archimedes. These are designed to improve the speed of filing operations by doing work at optimum times. There are some side effects of using them though. When active under RISC OS v2.00 and v2.01 discs *must* be dismounted before being removed from the floppy drive. Failure to do so results in the dreaded 'FileCore in use.' error. However if you are prepared to sacrifice the speed improvment they give configuring the buffers to 0 does remove this problem. (Or so I am informed.) Under RISC OS v3.00, as supplied with the early A5000 machines, these buffers generate a different problem and must *always* be configured off. Failure to do so results in spurious errors when using the Hard Drive on an early A5000. Symptoms include reformating of crucial sectors of the disc, disc address errors and general failure to save files to the drive. So when using an A5000 with RISC OS 3.00 remember to configure them to off! With RISC OS v3.10 all of the old problems have been cured with a new one introduced. Namely that if you have only a few ADFSBuffers configured and are accessing the floppy drive then your machine can occasionally lock up completely for you. It appears that any value of ADFSBuffers above 8 causes that problem to be largely alleviated (read it only occurs rarely at these settings). So under RISC OS 3.10 it is reccomended that you set your ADFSBuffers to 8+. There is a patch module available, called ADFSUtils, that does fix this problem - contact your local dealer for a copy of it. As for the optimum settings for ADFSBuffers, as far as I am aware no one has done any speed tests to see what is the best setting. Presumably though Acorn will have arranged for the system to start up (Well except for RO3.00...) in the optimum state for most uses. I would be interested in anyone who has done speed tests sending me the results of their investigations.... ---------------------------------------------------------------------------- Q19) What is the current File-type allocation ranges and why won't Acorn provide a full file-type list? Acorn have reallocated the File-type ranges for applications. The new ranges are :- Non-user area &E00-&FFF Acorn &B00-&DFF Commercial software &A00-&AFF Acornsoft, and other commercial software &400-&9FF Commercial Software User area &100-&3FF Non-commercial distributed software (ie PD) &000-&0FF User's personal usage (ie non-distributed) 75% of the user area is for PD/Shareware, with allocations co-ordinated by Acorn. If your software is going to be distributed, you should have an allocated filetype to avoid clashes. Acorn cannot publish it's master list of filetypes because, at any given time, it will contain allocations made for products which have not yet been announced. Therefore, Acorn would be in breach of confidence by doing so - and the editing overhead for producing a sanitised list is too great. ---------------------------------------------------------------------------- Q20) My disc gives me a 'Broken Directory' or my Free Space Map is corrupt, what can I do? Unfortunately due to the highly complicated nature of the filing system data there is little that can be done easily. Your simplest and best way of correcting the problem is to backup as much software as you can and reformat your drive, restoring everything from those backups you make regularly... (What you don't back up your discs? :-) ) To do anything else requires a good knowledge of how the underlying structures work and is beyond the scope of this FAQ, although this detail is covered in the RISC OS 3 PRMs. ---------------------------------------------------------------------------- Q21) My hard drive gives me disc errors when I use, what do the error numbers mean? The error numbers returned indicate the type of error encountered. Exactly why slightly more meaningful messages are not returned I am unsure. The error codes meanings are as follows :- 06 unit select signal has not been returned by drive 07 write fault signal from drive 08 drive not ready 09 seek complete has not been returned 10 data error has been detected by ECC (Error Correction Code) 13 a fatal ECC error has occurred in DATA area 16 sector ID has not been found 17 an ID area that begins with an improper address mark has been detected 18 the address mark in DATA has not been detected ---------------------------------------------------------------------------- Q22) What does the power on self-test check and how does it signal errors back to you? The purple screen at power on indicates that the self-test has begun. A brief ROM, RAM, VIDC and IOC test is performed and then the screen colour changes to blue and a full memory test is performed, along with a second test of the VIDC and IOC. When the screen returns to purple, the machine is testing for an ARM3. At the end of this sequence the screen colour is set to green (for pass) or red (for fail). If the tests have all passed then the machine starts to boot and the RISC OS 3 welcome screen is displayed. If any test fails, the screen will remain red and the disc drive light will blink a fault code. A short flash is used to indicate a binary '0' and a long flash indicates a binary '1'. The bits are grouped into eight nybbles (blocks of four bits) with the most significant bit first. The lowest seven bits are a status word. The meaning of each bit is given below in hex :- 00000001 Self-test due to power on 00000002 Self-test due to interface hardware 00000004 Self-test due to test link 00000008 Long memory test performed 00000010 ARM 3 fitted 00000020 Long memory test disabled 00000040 PC-style IO world detected Bits 8-31 indicate the fault code and are described below. Not all the bits are used. 00000200 ROM failed checksum test 00000400 MEMC CAM mapping failed 00000800 MEMC protection failed 00004000 VIDC Virq (video interrupt) timing failed 00008000 VIDC Sirq (sound interrupt) timing failed 00020000 RAM control line failure 00040000 Long RAM test failure Some third party VIDC enhancers on older hardware trigger the self test to fail. If you are getting a failed self test with a VIDC enhancer, yet the machine is working fine, enter this command and save your CMOS settings :- *FX 162,&BC,&80 This modifies the self test to cope with the VIDC enhancer. ---------------------------------------------------------------------------- Q23) Is there a Modula 2 compiler for the Arc? Currently, no. Acorn did have, in the early days of the experimental ARM work, an in house compiler. However this compiler was sufficiently unstable and buggy to be unreleasable as commercial product and was only used because in house support was available immediately to the users of the compiler. When Olivetti invested in Acorn this technology went to them so that Acorn no longer have even an in house Modula 2 compiler. However some companies have stated intentions to produce Modula 2 compilers for the Arc. Whether these intentions become reality has yet to be seen. ---------------------------------------------------------------------------- Q24) Is Virtual Memory possible under RISC OS? Short answer, full VM is *not* possible under the current versions of RISC OS. The problem is that most of RISC OS works in SVC mode, if a DataFetch abort occurs then R14_svc *is* corrupted. This makes returning from the SWI somewhat problematic. This is a hardware limitation with the ARM2 and ARM3 cell chips. Future hardware using ARM6 or better processor cells have special memory abort modes that alleviate this problem so future machines and incarnations of RISC OS may well have VM available. However limited solutions are available now. !Virtual is one such solution allowing VM for a user process using a limited subset of SWI's that are carefully 'protected' against R14_svc being corrupted. Such solutions suffer from the restricted set of SWI's they support and are mostly useful for batch style processing jobs like compilation or memory intensive processing jobs. ---------------------------------------------------------------------------- Q25) How compatible with other systems is an Archimedes? PC :- The Archimedes can handle DOS discs (720k; the A5000 and later models can also handle 1.44M floppies). In RO3, this is built in, under RO2 you have to use one of the (PD) utilities. There are two PC (software) emulators that can handle most PC software, three if you count the fact that Acorn's offering is split into two emulator programs. There are also PC cards, containing an 80x86 processor and other PC hardware, which uses the Archimedes' disc and video. All emulators are multitasking (and not PD). Unix :- Unix software can be ported (and in fact many packages already have been) with the help of UnixLib, which is PD. Memory-hungry ports, such as gcc, can be run with the aid of !Virtual (also PD). Of course if your really desperate to run Unix software it might be advisable to buy RiscIx, the Acorn flavour of Unix. Mac :- Due to the pecularities of the double density Mac disc format it is difficult to read the Mac disc directly. However a company is releasing a filing system and drive combination to read Mac high density discs allowing transfers. Also Macs often can read PC format discs allowing transfers to occur using that medium. There is no Mac emulator available. Atari ST :- Like PC floppies, the Archimedes can read, write and format ST-format floppies. No emulator for the ST is known. Amiga :- The amiga uses an unusual disc format that is not easily read by other machines. Accordingly there is currently no Amiga format disc reader available. But Amiga's can read PC discs, so again transfers can occur via that medium. There is no Amiga emulator. Spectrum :- There seem to be a couple of Spectrum emulators around, but (according to rumour) they can't be distributed legally because they require the contents of the ROMs, and Sinclair still holds the copyright. ---------------------------------------------------------------------------- Q26) What Acorn related companies are available on the net via email? There are quite a few companies now on the net and reachable via email with more joining as time passes. Here is the list of companies that have given permision to be entered here in the FAQ. If the email address is to a person rather than either an automated system or perhaps a group of people I have placed the name of the person in brackets after the email address description. Acorn Computers (Uk) :- vhancock@acorn.co.uk Specials needs enquiries. (Vorn Hancock) Aleph One :- Sales@aleph1.co.uk Information about products and prices. Support@aleph1.co.uk After-sales support. Atomwide :- Sales@atomwide.co.uk Information about products and prices. Support@atomwide.co.uk After-sales support. Colton Software :- info@colton.co.uk Automated reply, listing services available. sales@colton.co.uk general sales etc. support@colton.co.uk technical support on existing products. Computer Concepts :- info@cconcepts.co.uk Automated reply, giving information. sales@cconcepts.co.uk For credit card orders of products. support@cconcepts.co.uk Technical support for products. Comspec :- acorn_info@comrad.comspec.com Canadian Acorn dealer. Enquiries about Acorn hardware and products welcome including USA enquiries. (Domenic DeFrancesco) David Pilling Software :- david@pilling.demon.co.uk All enquiries to this address. Iota Software :- support@iota.co.uk Enquires & support for Iota products. Learning Curve Software Systems :- banks_p@kosmos.wcc.govt.nz Enquiries & technical support. (Philip R. Banks) howard_s@kosmos.wcc.govt.nz Enquiries. (Steve Howard) wright_j@kosmos.wcc.govt.nz Enquiries & technical support. (Julian Wright) SENLAC Computing :- sykesp@senlac.demon.co.uk Enquiries etc. (Peter R. Sykes) The Serial Port :- altman@cryton.demon.co.uk Software support. bob@cryton.demon.co.uk Retail enquiries. jim@cryton.demon.co.uk To reach Jim Nagel, author of the Acorn column in Computer Shopper magazine. pcats@cryton.demon.co.uk Hardware support Uniqueway :- info@uniqway.demon.co.uk General queries, product related or otherwise. support@uniqway.demon.co.uk Support for products. (Serial number should be quoted where relavent.) sales@uniqway.demon.co.uk For credit card orders. Warm Silence Software :- Robin.Watts@prg.ox.ac.uk Enquiries etc. (Robin Watts) If you are a company and you would like to included in this list please send me an email, to the address specified at the bottom of the FAQ, detailing the email addresses and their general function. I will then include them into the FAQ. ---------------------------------------------------------------------------- Thanks go to all the people who have contributed corrections and additions to the list. Without this help this list would be a hell of alot buggier (spot the programmer... :-) ) than it is... ---------------------------------------------------------------------------- All additions, corrections & suggestions for the FAQ List should be sent to -=> banks_p@kosmos.wcc.govt.nz <=- Being the maintainer of this FAQ I reserve the right to be wrong, incorrect, slow, out of date and generally how I please with the FAQ List.