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Twylo
May 23rd, 2014, 09:25 AM
I just picked up a Packard Bell Pack-Mate PB800. It's got the following specs:


80286 CPU
1MB RAM
C&T CS8221 Chipset
Phoenix BIOS
WD1003V-MM2 MFM Controller


I was hoping to use this box as a general-purpose MFM drive tester and formatter, but I can't seem to find the Winchester controller BIOS, and no drives are being recognized. Now, it's been a while since I actively used a 286 -- I'm sure I'm just missing something obvious here, so hopefully someone can help me.

I've tried the obvious addresses. I boot DOS 5.0 off a floppy and run DEBUG, then I do:

-D C800:0
-D CA00:0
-D CC00:0
-D CE00:0

But none of these return anything but FF FF FF FF FF FF... There appears to be no WD1003V-MM2 ROM BIOS at any of the expected addresses!

There are a whole slew of C&T CS8221 BIOS settings dealing with EMS and shadowing, but it's been so long that I honestly don't remember what they do. One of the obvious ones is "EMS Base Address at C800", which I would expect to conflict with the expansion cards -- but I've tried moving that, and it doesn't seem to do anything.

Can any 286 experts guide me to the right solution?

-Twylo

Stone
May 23rd, 2014, 10:01 AM
I've tried the obvious addresses. I boot DOS 5.0 off a floppy and run DEBUG, then I do:

-D C800:0
-D CA00:0
-D CC00:0
-D CE00:0Sorry, but those addresses don't appear as obvious address to me. :-)

These are:

G=C800:5 (This is the most likely as it's a WD controller)
G=CA00:5
G=CC00:5
G=CE00:5

If none of those work you'll need a disk based formatting tool such as SpeedStor.

Twylo
May 23rd, 2014, 10:06 AM
Hi Stone!

Sorry, I should have been more clear -- I did try the "G=C800:5" and so on, first, but all of the commands hung. That's when I turned to D command (dump) to view what's actually at the addresses I specified. But they're all empty. I'd expect to see a dump of the first 80h bytes of the Winchester ROM at one of the addresses, but all of them are just FF FF FF FF FF...

-Twylo

Chuck(G)
May 23rd, 2014, 10:07 AM
Stone, he's just looking for the BIOS, he's not interested (at this point) in executing it.

My WD sheet for the 1003V-MM2 says that if you want to LLF, you need a setup disk--could be that there's no BIOS in this one.

RuudB
May 23rd, 2014, 10:14 AM
Hallo Seth,

You didn't find a BIOS because there isn't one. That is, the needed instructions are incorporated inside the BIOS of the board itself. To format and test a HDD you need a program on floppy. In the '80s I used a program called SpeedStor. See: http://www.minuszerodegrees.net/software/speedstor.htm.

Regarding EMS: these registers are chip dependent and are different for various boards. My advice: don't use EMS unless you really need it.

I hope this helps :)

modem7
May 23rd, 2014, 03:07 PM
Can any 286 experts guide me to the right solution?
In the IBM PC and IBM XT, the motherboard has no BIOS support for hard drives. So, the hard drive controllers for PC-class and XT-class computers have a BIOS expansion ROM on them, to provide BIOS code to control the hard drive.

In the move to the IBM AT, IBM added (limited) hard drive support into the motherboard BIOS, and so rarely will you find a BIOS expansion ROM on an AT-class hard drive controller. Your 286 machine will be an AT-class one.

Certain AT-class hard drive controllers have a BIOS expansion ROM. For example, SCSI controllers.

Chuck(G)
May 23rd, 2014, 03:15 PM
...and so rarely will you find a BIOS expansion ROM on an AT-class hard drive controller. Your 286 machine will be an AT-class one..

I've have a pile of 16-bit AT controllers with BIOS ROMs on them from several manufacturers. In fact, I have more of those than ones without.

The catch is that they're all RLL controllers. My experience with RLL controllers after about 1986 showed me that most of the better brand drives were perfectly capable of RLL without so much as a peep--probably due to the use of plated media. It just didn't make any sense to buy a MFM one, when, for a small bit extra, you could expand your storage by 50%. In my opinion, you were nuts not to do it. IDE drive manufacturers incorporated RLL right from the start.

Twylo
May 23rd, 2014, 03:43 PM
Thanks for the info, everyone! I downloaded SpeedStor and managed to get it working. I'm able to format drives, finally. Woohoo!

-Twylo

modem7
May 23rd, 2014, 03:50 PM
I've have a pile of 16-bit AT controllers with BIOS ROMs on them from several manufacturers. In fact, I have more of those than ones without.

The catch is that they're all RLL controllers. My experience with RLL controllers after about 1986 showed me that most of the better brand drives were perfectly capable of RLL without so much as a peep--probably due to the use of plated media. It just didn't make any sense to buy a MFM one, when, for a small bit extra, you could expand your storage by 50%. In my opinion, you were nuts not to do it. IDE drive manufacturers incorporated RLL right from the start.
I was careful to use "rarely" to reflect what I consider to be the norm. I concede that "rarely" can be enterpreted differently of course. For some, it might be 1 in 10. For some it might be 1 in 1000.

The subjects of ST506/ST412 drives, XT-class versus AT-class controllers, low-level format, etc. comes up frequently. When I get some time, I'll create a web page that can be pointed too.