Ibm Pc At 5170

[Paul Stenning]

Yes, you were supposed to run the utility to park the hard drive heads before moving the PC. Early hard drives were very delicate, and knocking the table while the PC was running could be enough to damage it.

With the one I gave to Dave, the hard drive in the machine is faulty anyway and the other hard drives have not been powered up by me. Some are slightly newer though, and don't need the heads parked.

[liamoliver]

Incidentally, when did the type of hard disc that needed parking fall out of favour? I've never been able to get a head parking utility.

[Paul Stenning]

Incidentally, when did the type of hard disc that needed parking fall out of favour?

As soon as the hard drive manufacturers came up with an improved design that didn't need it.

I've never been able to get a head parking utility.

There are a few head parking utilties in the Simtel MS-DOS collection on the Disk Utilities page here http://www.eunet.bg/simtel.net/msdos/diskutil.html

[Dave Moll]

Liam, if you need a head parking utility (i.e. you too are playing with ancient hard discs), I can let you have one. Let's continue this discussion by PM.

Returning to the main saga - the progress so far:

Paul, I have followed your advice and replaced the lithium battery pro tem with a pair of AAs. The configuration memory is now holding its contents, though the clock would appear to stop when the machine is switched off (I went out for a few hours and was given my leaving time as the system time when I returned home and switched on again).

I have now found the SETUP program on the "Walters AT setup disk" (now copied from 3½" disc to 5¼"), so I now have the means to set the configuration. I have not yet found a disc type that matches an actual hard disc. I have tried all possibilities with the Tandon disc without success - and that is one which I would expect to work. As there is a second pair of cables with this unit (rendering my previous comment about not having a spare set untrue), I may try the suggestion of swapping cables after repeating the above exercise with another disc.

Unfortunately, I have not been able to find any cylinder/head information on any of the discs, so have been unable to make use of the disc parameter table - hence the laborious working through all possibilities.

Additionally, if I tell the system that there is a hard disc present, it will try to boot from that even if I have a floppy disc in the drive - unlike my XTs which will check the floppy first and later machines which are programmable in the BIOS. There doesn't seem to be a way to tell it to boot from floppy if a hard disc is present. If, however, I tell it that no hard discs are installed, it happily boots from floppy - or into BASIC from ROM if no floppy is present.

[Mike Phelan]

Dave
I've come into this thread late, and may have missed some of the replies, but are the two hidden system files on the HD? IO.SYS and MSDOS.SYS? Also COMMAND.COM is needed to boot.

The first two cannot be just copied - they must be in the beginning of the root directory as when they run, the OS deos not yet exist. SYS.COM on a floppy is used to install them.

Beware of changing HD details in the BIOS - it is possible to trash any files on the HD.
I think earlier PCs automatically try to boot from HD if a DOS partition entry is found.

Apologies if you knew all this!

[Dual Standard]

Dave,

According to the IBM Service Information Manual the battery should be 6.0 Volts minimum and this should be measured with the battery disconnected. If the machine was keeping date & time with the original battery and is not posting a 161 (battery defective) message duing the power on tests then the battery was probably OK.

The diagnostic diskette you mention in post #13 and the diskette image from the site that Kat mentions should be bootable and will allow you to configure the bios, low level format the hard drives etc etc.

I cannot remember any way of changing the boot sequence in a 5170, it should always try to boot from the A diskette drive first. However if it has a hard drive that is either faulty or unrecognisable for some reason it will pause for several minutes with the hard disk light on apparently trying to boot from it but if left long enough it will post an error then boot from the diskette drive.

If any of the drives are pukka IBM ones they should have a 'type' number on their label.

Hope this helps.
Mike

[Paul Stenning]

Originally Posted by Dave Moll

Unfortunately, I have not been able to find any cylinder/head information on any of the discs, so have been unable to make use of the disc parameter table - hence the laborious working through all possibilities.

There should be printouts of the parameters of most of the hard drives in the box, which will contain the head, track and sector info in the specs. If they are missing, try http://www.pc-disk.de/ which is where I printed them from.

Is there a half-height 5.25" 40MB Seagate drive? If so, that was a type 40 on the Walters machine.

The 3.5" half height Seagate may be faulty. That came from where I used to work. They had a few in the stores (new old stock) for repairing old equipment that used them, and only 1 in 3 worked when first tried. However that one was working when the unit it came from was discarded.

The big Micropolis should be good. I think that is slightly newer so the heads should self-park. It may be too big to be supported by the BIOS though, and may be RLL rather than MFM.

The Tandon may also be slightly newer. It would originally have been supplied with a controller card for an XT machine (I never had that) so it may be also RLL rather than MFM.

As mentioned above, if the BIOS cannot initialise the hard disk it will take several minutes before reporting the error and booting to floppy.

If Mike is right about the BIOS battery, that could explain why the clock isn't running. What was printed on the original?

[Dual Standard]

Pauls post reminds me.

As well as the RLL drives there were also ESDI drives that used the same connectors as the MFM ones and and would physically fit but not work in a standard 5170. I am also sure the original 5170 only supported MFM not RLL drives.

Mike

[Dave Moll]

Originally Posted by Paul Stenning

There should be printouts of the parameters of most of the hard drives in the box, which will contain the head, track and sector info in the specs. If they are missing, try http://www.pc-disk.de/ which is where I printed them from.

I hadn't dug down quite that deep. I have now found information on the Seagate and Micropolis drives. I will peruse these and see where that gets me.

Is there a half-height 5.25" 40MB Seagate drive? If so, that was a type 40 on the Walters machine.

There is a Seagate 3½" (marked "good 06-12-01"), a Tandon 3½" and an NEC Corporation 5¼" - all half-height. If it is a type 40 for this m/c that would be a problem. The only options are 1-14 or 16-23. In addition there are two full-height 5¼" drives - a Micropolis and the original IBM. I have noted your comments about the Micropolis and Tandon.

If Mike is right about the BIOS battery, that could explain why the clock isn't running. What was printed on the original?

Indeed, now that I have taken a closer look, it does say "6V" - I have added another pair of AAs to my temporary setup and I'll see whether that sorts it. The rest of the setup information was being retained OK at 3V.

Watch this space...

[Dave Moll]

Originally Posted by Mike Phelan

Beware of changing HD details in the BIOS - it is possible to trash any files on the HD.

Worth bearing in mind if I succeed in gaining access to one of the discs. As far as I know, DOS doesn't attempt to write to the hard disc in the process of booting, so it should simply be a matter making 99.999% sure that I have selected the correct disc type before attempting to store anything on the disc.

[Paul Stenning]

I doubt there is anything useful on any of the hard drive currently, anyway.

The Micropolis and Seagate came from Unix systems so won't have anything on them that a PC can do anything with. The Tandon is new (so should have nothing on it) and the NEC is completely unknown. The IBM is dead anyway, but did have the remnants of DOS 3 until I tried (unsuccessfully) to low level format it.

You don't have the Seagate I was thinking of then. I couldn't remember whether I still had it from all those years ago - obviously not.

With the heads, sectors and tracks - you should be able to choose a drive from the BIOS which has figures less than or equal to the ones for the drive. It should then work but you won't get the full capacity. Choosing a drive type where any of them are larger than the drive will cause it to fail to boot.

It may be worth choosing a drive type with low figures (such as a 5MB or 10MB one) and seeing if any of the disks can then get past the test on booting.

[Dave Moll]

OK, so I've taken the coward's way out for the time being. I have reinserted the hard card and told the BIOS that no hard disc is installed. I am now successfully booting from the hard card as drive C. I may return to the attempt to run from a "proper" hard disc at a later stage. For now I have a working DOS 5 system running from hard disc, from which I can start playing with other areas such as: colour monitor; Windows 2; mouse etc. The other advantage with this setup is that I CAN boot from floppy if I wish (which is just as well, because I can't disable the hard card without physically removing it).

The problem before was that it was attempting to boot from the disc which it couldn't find rather than from the hard card. The hard card was then defined as a second (non-boot) hard disc, but was still assigned as drive C because the first disc had failed.

[Paul Stenning]

I guess it's possible that the hard drive controller has been damaged by connecting to an unsuitable drive (such as connecting the MFM card to a RLL drive). I don't know whether that would cause damage or not.....

It'll be interesting to hear how you get on with the EGA monitor (as I never tested it) and assorted EGA cards.

There are also a few memory cards (with no info at all so it's guesswork) which I was hoping would let me get 1MB of RAM so DOS can be loaded high. That's the limit of a 286 I believe. There is already a small memory card in one slot, increasing the motherboard 512K memory to 640K.

It may be useful to fit one of the 3.5" floppies as a B: drive too. You'll probably only get 720K though, as the BIOS doesn't support 1.44MB drives.

[Dave Moll]

Originally Posted by Paul Stenning

I guess it's possible that the hard drive controller has been damaged by connecting to an unsuitable drive (such as connecting the MFM card to a RLL drive). I don't know whether that would cause damage or not.....

I had started to wonder whether the problem lay with the controller. As I say, I'll stick with the hard card for now.

It'll be interesting to hear how you get on with the EGA monitor (as I never tested it) and assorted EGA cards.

My first attempt with Paradise Basic EGA Card resulted in a display crushed at the left hand side, but otherwise displaying text OK. I haven't tried displaying graphics yet.

What I currently have installed is a card which is switchable between MDA and CGA. Yes, the quality of CGA display is terrible, but this board gives me the use either monitor at the flick of a switch for the time being.

There are also a few memory cards (with no info at all so it's guesswork) which I was hoping would let me get 1MB of RAM so DOS can be loaded high.

That would be a good target to aim for at some stage.

[Dual Standard]

Originally Posted by Paul Stenning

I guess it's possible that the hard drive controller has been damaged by connecting to an unsuitable drive (such as connecting the MFM card to a RLL drive). I don't know whether that would cause damage or not.....

When Xt's & At's were cheap (i.e. free) and plentiful some 10 or 15 years ago we did lots of experimenting with different hard drives, especially ones never intended to be fitted to PCs, I don't ever remember damaging a disk controller card though connecting an incorrect drive. In fact I don't remember having to replace a disk controller card in any of the machines we had on maintenace , motherboards, memory modules, drives, the occasional power supply yes, controller cards no.

The 720K limit on 3.5" diskettes is not only a BIOS limitation but also a hardware one within the controller card.

Mike

[Dave Moll]

Originally Posted by Paul Stenning

It'll be interesting to hear how you get on with the EGA monitor (as I never tested it) and assorted EGA cards.

The EGA display has now been much improved now that I have found the Ultimate EGA card and substituted that instead of the Paradise one. There is still a very small amount of foldover at the beginning of a line of text, but only a slight flattening of the left-hand edge of a letter rather than total loss of the first letter - which I was experiencing before. I may at some stage open up the monitor to see whether there is an adjustment for horizontal positioning - there are only vertical controls externally.

All I need now is an application that makes use of EGA graphics. So far the only graphics displayed have been CGA.

There are also a few memory cards (with no info at all so it's guesswork) which I was hoping would let me get 1MB of RAM so DOS can be loaded high. That's the limit of a 286 I believe. There is already a small memory card in one slot, increasing the motherboard 512K memory to 640K.

The first one I tried (with ICs on the board rather than SIMMs) refused to go into the slot (must be fractionally bigger edge connector, but looks no different to my naked eye), so I tried the one with four SIMMs and now have 4MB of extended memory, so everything possible is now loaded high.

The only down side is that the memory check at switch on now takes somewhat longer. A bit of a pain at present when I am constantly powering off and on again, but worthwhile if I actually end up running applications which can make use of the extra memory.

It may be useful to fit one of the 3.5" floppies as a B: drive too. You'll probably only get 720K though, as the BIOS doesn't support 1.44MB drives.

Yes, I've done that - the one with a 5¼" face plate, which I think really looks the part.


I installed the software for the Microsoft Mouse, but find that the movement sensors in the mouse itself don't seem to be working. It is not that the ball is slipping on the (sturdy metal) rollers. Even going inside and turning the rollers fails to move the cursor. Occasionally the cursor twitches (I can describe it no better than than that), but no reliable movement. I may take a closer look at the innards of the mouse later, but have installed a serial mouse for the time being. Mind you, I haven't installed any mouse-driven software yet, so have not been able to test it.

I think I might now take a chance on putting the cover back on the system unit, as I now invisage concentrating on software for the time being.

On the subject of software, I was hoping to install Windows 2.0, but that does not seem to work any better than when I tried it on my Amstrad 1640. It displays a (CGA mode) startup screen, then displays a load of garbage and freezes.

Having failed with Windows 2.0, I tried with a copy of Windows 1.01 which I have. Unfortunately, I just have all the files in one large ZIP file, but running setup expects to read files from floppy discs - and I don't know what it would expect to be on which disc.

[Paul Stenning]

Originally Posted by Dave Moll

All I need now is an application that makes use of EGA graphics. So far the only graphics displayed have been CGA.

I should have some EGA card games somewhere - I'll have a look tomorrow...

Having failed with Windows 2.0, I tried with a copy of Windows 1.01 which I have. Unfortunately, I just have all the files in one large ZIP file, but running setup expects to read files from floppy discs - and I don't know what it would expect to be on which disc.

I have probably got a copy of that too. I have a few hundred megs of old software somewhere. If I can find it I'll send you a CD.

[Dave Moll]

That's most kind, thank you.

[Dave Moll]

Originally Posted by Dave Moll

I was hoping to install Windows 2.0, but that does not seem to work any better than when I tried it on my Amstrad 1640. It displays a (CGA mode) startup screen, then displays a load of garbage and freezes.

I have just proved my theory about the "garbage" by swapping the EGA graphics card and monitor for VGA ones. Windows 2 now works fine.

On the other hand, I would prefer to stick with the EGA monitor, which looks appropriate for the 286. Is there any way to persuade Windows 2 to operate in EGA mode?

[Paul Stenning]

Well I'm sure Windows 3.0 worked in EGA mode so I would expect Windows 2 to do so....