This section complements the 'Problems' section of the User Guide. We have tried to keep the User Guide fairly short to make it readable, and most users will not require any further information. However, if you do want to know anything not in the User Guide or have difficulties read this file BEFORE you phone/write/email etc. I have become rather fed up with users who send a long involved email to which I have to reply, only to get another message later which says, in effect, that I'd wasted my time because AFTER they'd sent the email they found the answer in the User Guide. So, although I may reply EVENTUALLY to queries to which you could find the answer yourself, they won't be dealt with with urgently.
Dave Holden (2002)
1. I'm confused about IDEFS, ADFS, CDFS, SCSI etc.
2. I get a long delay when I switch on with the message 'Waiting for hard drive'.
3. Why IS there such a long delay when ADFS and many SCSI interfaces are much quicker?
4. There is a VERY long delay when I start up and when I get to the desktop there are two hard drive icons. One just says 'IDE:4' and when I click on it the computer 'hangs'.
5. I get an 'Address Exception' error and the computer stops with a blank screen and a '* prompt.
6. The correct number of drive/CD icons don't appear and the message telling how many drives were found is too fast to read.
7. I've just fitted a new drive and the drive icon is feint and I can't access the drive.
8. I've just fitted a hard drive and now the floppy drive icon has vanished and the light is on all the time.
9. The computer stops with a blank screen and a message 'File ***** not found'.
10. When I try to run a program it tells me that it is corrupt or that I must re-install it.
11. My !Boot file isn't run and I get a message 'Drive not found'.
12. I get a message 'File !Boot not found'.
13. I see an error message 'Bad drive' and my !Boot file isn't run.
14. Is it possible to fit a drive activity light?
15. Why isn't the formatting/partitioning software a desktop program?
16. My hard drive/partition is named 'Fred' and sometimes the computer freezes when I check free space.
17. How can I make up a cable to connect to the 37 way 'D' socket?
18. I've got an 8.2 Gb drive but 'Free' says it's only 7Gb.
19. When I try to verify my IDE partition :8 from the command line I get a message 'Bad Drive'.
20. My new IDE drives on my RiscPC are working perfectly but I'm having problems with my SCSI drives.
21. My computer is on a network but 'Share' on the menu isn't working.
1. I'm confused about IDEFS, ADFS, CDFS, SCSI etc.
Acorn machines can have lots of different filing systems working side by side. As drives on different filing systems will often have the same drive number (eg. the first hard drive is normally drive :4) the operating system is designed so that instead of just a drive number (or letter as on a PC) all drives are also addressed by their filing system name. The 'built in' filing system is ADFS (Advanced Disc Filing System) and this normally controls the floppy drives. Where the hard disc interface hardware is completely integrated with ADFS, as with the IDE interfaces fitted to the A5000, A3020, A4000 and RiscPC, and the ST506 drives fitted to A400 machines, the hard discs are part of ADFS.
With a few exceptions add-on interfaces have their own filing system
name so there's no conflict with ADFS. With SCSI interfaces this is
normally SCSIFS (or just SCSI) and with third-party IDE interfaces it's
normally IDEFS. It is important to understand that an IDE drive attached
to an ideA interface would be addressed as IDEFS
Some hard disc interfaces, although not physically built-in to the computer, still use ADFS as their filing system. For example, the ST506 interfaces fitted to the original A440 and A310 machines and IDE interfaces manufactured by Castle Technology and some others. The disadvantage with this is that because they are integrated into ADFS this type of IDE interface cannot be used in conjunction with the built-in hard disc interface on machines like the A5000 or RiscPC.
2. I get a long delay when I switch on with the message 'Waiting for hard drive'.
The delay should be in the order of 5-15 seconds and depends upon how many devices are attached and how quickly they respond. A bus with two devices or an empty bus will respond quickly, a bus with a single device will respond more slowly because the interface can detect that something is connected, but it has to wait until the second device doesn't respond to be sure that only one is attached. So, if you have two devices you will get a shorter start-up delay by connecting both to the same bus as Master and Slave, although this might not always be possible.
You can't speed up this process by using the 'IDEFSDiscs' mask. This might make things worse, especially if it's used wrongly. Before you try to use it read the User Guide carefully. If you use it to set a drive that isn't present the start-up delay will get a LOT longer as the interface tries very hard to find a drive that you have told it is there but which, in reality, isn't. I have often found that excessive delay is caused by an improperly used IDEFSDiscs configuration. Unless you are sure of what you are doing use the default configuration:
*Configure IDEFSDiscs 0
which enables auto-detection.
A DELETE-Power-On might help. (Hold down the DELETE key, switch on the computer, and keep it held for a few seconds). This resets the CMOS RAM to its default settings. You will lose anything you've changed, so you will need to run !Configure and restore a few items to your chosen settings, (double-click on !Boot with a Risc-PC) but if something in CMOS has been altered this MIGHT make a difference.
If the dealy occurs BEFORE the 'Waiting for hard drives' message then, if you don't have a CD ROM attached to the built-in IDE interface but DO have one connected to the ideA card, *unplug CDFSSoftATAPI to disable the built-in ATAPI CD drivers will normally cure the problem. This shouldn't make any difference in theory, but it may help, and sometimes seems to be the cause of long delays with Series 1 RPCs (those originally fitted with RO 3.5) which have been fitted with RO 3.6. Fitting RO 3.6 is NOT a legitimate upgrade for these machines. It only happens because there are surplus 3.6 ROMs taken from machines which have had a Strong ARM fitted and have been upgraded to RO 3.7. The CD and hard disc software in RO 3.6 was not meant to be used on Series 1 machines, and although there's nothing basically wrong with fitting RO 3.6 to these machines it can cause minor problems of this type.
3. Why IS there such a long delay when ADFS and many SCSI interfaces are much quicker?
The IDE interface has a lot more to do when it starts up, and most of these things depend on how quickly the drive is ready.
The first thing any filing system has to do on startup is to report to the Filer how many drives it controls so the correct number of icons can be displayed. With ADFS, !Configure sets the number of drives present, and as ADFS doesn't support partitioning it can immediately declare how many icons it needs. That's why ADFS will install an icon on the iconbar for a configured drive even if it isn't present. The IDE filer first has to scan the two IDE busses and look for drives. This is normally fairly fast as it's only neccesary to talk to drive firmware to find out if there's a drive there, but it's only the beginning. It next has to read the partition table from every drive. Until it reads the partition table it only knows how many physical drives there are, not how many logical drives, and it's the number of logical drives that must be reported to the filer. This means waiting until the drive has run up to speed, intialised itself, and is ready to be used. Some drives can be ready in a couple of seconds, others can take up to twenty.
This explains why trying to use 'Configure IDEFSdiscs' to speed up this process doesn't work. It is still neccessary to wait for the drive to be ready and read the partition table, so just knowing that a drive is present doesn't help.
Quite a lot of CMOS RAM was allocated to SCSI cards so they are able to store all of this information in CMOS RAM. The number of partitions on each drive and which icon should be linked to which partition, can all be stored in CMOS, so unless the data changes it is available instantly to the SCSI interaface which can report the correct number of drive icons required to the filer without the need to mount the drive and read the partition table. Unfortunately only four bytes are allocated to IDE interfaces, so there isn't room for the data for IDE drives to be stored, it has to be read every time the computer is started.
With versions of IDEFS from 3.26 the time IDEFS waits before deciding there's no drive attached can be configured. You can set this using:
Configure IDEFSStartUpDelay <number>
where
4. There is a VERY long delay when I start up and when I get to the desktop there are two hard drive icons. One just says 'IDE:4' and when I click on it the computer 'hangs'.
This is what happens when you move a drive from the built-in IDE interface to an ideA interface or remove an ST506 drive from an A400 and don't 'un-configure' the original drive. Drives connected to the APDL IDE interface are NOT anything to do with IDE drives connected to the built-in IDE interfaces on the A5000, A4000, A3020, A7000 and RiscPC.
You can't use !Configure to set the number of IDEFS drives
You MUST use !Configure to un-configure any drives you move from the built in interface to a IDE card.
As Acorn's IDE interface isn't self-configuring, if you remove a drive and don't un-configure it there will be a VERY long delay (minutes!) each time it tries to access the drive, eg. at switch on and if you click on the drive icon. Note that the IDE interface manufactured by Castle Technology DOES use !Configure to set the number of drives as it works under ADFS. If you remove one of these interfaces and replace it with an ideA card you will need to un-configure the old hard drive.
5. I get an 'Address Exception' error and the computer stops with a blank screen and a '* prompt.
This is almost always caused by an internal data cable fitted the wrong way round. The cable should be plugged into an ARCIN card with the identifying stripe close to the edge of the circuit board (the left-hand side as you look at the computer from the front). Where the cable is plugged into a hard drive (or CD ROM) with almost all drives the stripe goes to the right-hand side as you look into the socket with the drive the right way up, ie. with a hard drive the metal part of the drive uppermost and the PCB at the bottom. Some very old drives have the socket the 'wrong' way, but these are very rare.
6. The correct number of drive/CD icons don't appear and the message telling how many drives were found is too fast to read.
As soon as the message 'Waiting for hard drive' appears hold down the SHIFT and CTRL keys. Wait about 20 seconds and then release the SHIFT key for a fraction of a second. Holding down both these keys 'freezes' all writing to the screen. Releasing the SHIFT key momentarily lets the messages appear and then freezes the screen again so you can read them.
7. I've just fitted a new drive and the drive icon is feint and I can't access the drive.
This implies that the drive isn't formatted. Most Acorn dealers supply drives ready formatted, but if didn't buy it from an Acorn dealer then it won't be.
8. I've just fitted a hard drive and now the floppy drive icon has vanished and the light is on all the time.
You've re-fitted the floppy drive data cable the wrong way round or it's only on one row of pins!
9. The computer stops with a blank screen and a message 'File ***** not found'.
This is what will happen if you move your main hard drive from ADFS to IDEFS and haven't edited your !Boot file(s). The filer is telling you that it can't find a file, presumably because the filename refers to ADFS not IDEFS.
The first time you switch on after moving a drive from ADFS to IDEFS you should hold down the SHIFT key. This stops !Boot from being run and lets you get to the desktop and edit the files.
There are dozens of different methods of setting up a !Boot file or
application, so it isn't possible to be specific, but if you've created
you own system you'll know where to look. With a standard RiscPC there
are two files to look at, !Boot.Choices.Boot.PreDesktop and
!Boot.Choices.Boot.Desktop. If the computer doesn't reach the desktop
the problem is in the PreDesktop file. With a non RiscPC machine you
will probably have just a file called !Boot. Load these into !Edit or
another text editor and look for references to 'ADFS::
10. When I try to run a program it tells me that it is corrupt or that I must re-install it.
This is often a software protection problem. Some programs won't run if you move them to another drive or computer and you have to re-install them. Sometimes you are only allowed a limited number of installations, so you might have to move the drive back to ADFS, un-install the program, shift the drive to IDEFS and re-install it.
If you get this sort of problem then please WRITE to the people that produced the program and complain. You'll probably be ignored or get a letter telling you how it's essential for them to do this to guard against software piracy. This is absolute rubbish. The only people inconvenienced by these stupid schemes are honest users, and the only way to stop such childish practices is to complain. There's no need to be apologetic (or even polite). Remember, they have inconvenienced you and made you waste time, let them know that you strongly disapprove.
11. My !Boot file isn't run and I get a message 'Drive not found'.
There are several possible causes for this, but the most common is that the configuration is wrong. If you want to boot from IDEFS then you must configure IDEFS as the default filing system and make sure that the drive with your !Boot file or application is configured as the default drive. Normally, but not necessarily, this would be drive :4. Note that with IDEFS it's the IDEFS drive that must be set, so use:
*Configure IDEFSDrive 4
NOT
*Configure Drive 4The configuration setting for 'Drive' sets the ADFS default drive.
12. I get a message 'File !Boot not found'.
This means exactly what it says. There must be a file or application called '!Boot' on the CONFIGURED default drive and filing system. That's the ONLY place the OS searches for !Boot, so you must make sure that the drive and filing system are configured correctly.
13. I see an error message 'Bad drive' and my !Boot file isn't run.
This has arisen a couple of times and it emerged that that the configured IDEFS Drive had been set to 0. As there wasn't an IDEFS Drive :0 the error message appeared.
If this happens repeatedly on an older machine that use dry batteries to hold the CMOS RAM settings when the computer is switched off (eg. A310, A400, etc.) it could be that the batteries need to be replaced.
14. Is it possible to fit a drive activity light?
Very early ideA interfaces were fitted with a LED, but we found that 95% of people never bothered to install it. This was because it's a major job to fit on an A310 or A400 (you have to remove the front panel) and there's no prepared hole in a RiscPC. When we introduced the new interface we therefore decided not to bother as a light would add to the cost, and most users would discard it anyway.
This decision seems to have been correct because after around 200 units were sold only two people had enquired about an activity light. However, with the Blitz, although we still do not supply an LED as standard, we have made it much simpler for those that wish to do so to fit one.
There are two holes in the PCB (see diagram in the User Guide) prepared for an LED to be connected. You can either solder the wires direct to these or solder two short lengths of wire to make connecting pins. There is no need to use a resistor, it is already fitted to the PCB. You MUST use a very low current high brightness LED.
15. Why isn't the formatting/partitioning software a desktop program?
Because it would tend to make it more awkward to use, not easier. This is not a program that you have to use often and it certainly doesn't need to multi-task. Lots of fancy windows might make it look more impressive, but a simple menu is much less confusing. At present it's very simple to use, and as it will be used only very infrequently (many people will probably never use it at all) this is pre-eminent.
As this program can completely wipe your hard disc it is important that you are aware that it's not just another utility, and leaving the desktop emphasises this. It's also not possible to have it installed on the icon bar while you leave the machine unattended so someone else can trash your hard disc by just 'fiddling about'.
For this reason we normally advise users NOT to copy !IDEFormat onto their hard disc if others have access to the computer.
16. My hard drive/partition is named 'Fred' and sometimes the computer freezes when I check free space.
There is a bug in the Desktop Free code which can cause erratic behaviour when used with drives with four character names. This is nothing to do with the IDE software and it can happen with ANY drive on ANY filing system. The advice is therefore NOT to use a drive or partition name with four characters.
17. How can I make up a cable to connect to the 37 way 'D' socket?
Use standard 40 way ribbon cable and omit leads 20, 32 and 34 from the 37 way end. To do this, carefully slit the cable either side of these leads and cut off the last 3 cm or so. Now close up the 'gap' and fit the 37 way IDC connector (it's easiest if you hold the cable together with tape). Then fit a standard 40 way IDC connector to the other end.
18. I've got an 8.2 Gb drive but 'Free' says it's only 7Gb.
There are two 'features' of Desktop Free that cause this. Drives over 4Gb have their size shown to the nearest full gigabyte below, so if your drive is 4.999Gb this will be 4Gb. Also most drive manufacturers calculate a gigabyte as 1000 x 1000 bytes, or at best 1000 x 1024 bytes. Acorn calculate it as 1024 x 1024, so drives appear smaller than quoted size. If you want to know what the actual free space on your drive is press F12 and type:
idefs free :4 (or whatever the drive/partition number is)
19. When I try to verify my IDE partition :8 from the command line I get a message 'Bad Drive'
This is because of the way the filer allocates drive numbers. The normal system is that drives 0 to 3 are floppy drives, and drives 4 to 7 are hard drives. This is how ADFS works, and this syetem obviously limits the number of hard drives or partitions to 4. So that IDEFS can support up to 8 partitions it has to use the 'floppy' drive numbers 0 to 3 for drives 8 to 11. This means that IDE drive (or partition) numbers follow the sequence:
4, 5, 6, 7, 0, 1, 2 3
So, IDE drive/prtition number 8 is really drive number 0, and to verify it you would use 'Verify :0'.
20. My new IDE drives on my RiscPC are working perfectly but I'm having problems with my SCSI drives.
This can happen with some makes of SCSI interface if they're not the only expansion card using DMA. Symptoms are failure to read a SCSI CD drive properly, corruption of files on a SCSI drive, etc. The most common problem can be fixed by putting the IDE card in a higher priority socket. This means putting it in the bottom socket of the backplane with the SCSI card above it. As this is a DMA problem it only happens with the RiscPC and only with 'fast' SCSI cards using DMA.
One common cause of SCSI/IDEFS compatibility problems is the 'background mode' used by some SCSI interfaces. Try running the SCSI setup software and discabling this (it's normally on some sort of 'advanced settings' dialogue). This is a known problem with Powertec and Cumana interfaces and can cause difficulties with things like scanners as well. This option is intended for use with high speed SCSI drives and will have little or no effect on any other SCSI devices.
Don't forget that if you do a DELETE-PowerOn then these settings may be reset so you'll have to alter them again.
21. My computer is on a network but 'Share' on the menu isn't working
To get Share to work you have to enter the command 'Share