• Please review our updated Terms and Rules here

Compaq Portable III

N

Neosodium

Experienced Member
Joined
Nov 30, 2010
Messages
119
Location
Oxfordshire, UK
Ok, I recently found a Portable III in reasonable condition other than some cracks and damage to the casing. It's upgraded to the teeth with 8mb RAM, a 386 CPU upgrade and the rear ISA expansion unit.

My objective is to get it booting DOS from an internal hard disk, and hopefully get GEM and Qbasic on it and a few other nice DOS apps. However, all I have succeeded to do so far is waste the better part of a day trying to make it boot from a DOS formatted HDD.

So far, I have learned this much:

The dallas DS1287 is flat, and I attempted to cut into it to wire a battery on but the negative pin broke off the chip. I have ordered a replacement (a DS12887) but for the time being I won't be able to save bios settings.

The original hard disk has failed, so i'll have to use a more modern one, but I have no idea even how to set the machine up to read/boot from its original letalone a replacement.

I'm currently trying to source the diagnostic/setup diskette and find a spare 5.25 disk to put a temporary dos installation on.

Any help/advice would be very appreciated, as I'd love to get this machine going properly - I have wanted one for ages and I love the red plasma display and how it all folds out :)
 
A trick that worked for me with a Compaq Portable 386: Put in a more modern IDE hard drive bigger than the BIOS can actually handle (I think mine was 1.2 GB or something like that). Then when you get the setup disk, set the drive type to the largest size (in MB) supported, ignoring all the drive setup information. My unit now boots just fine off the drive, thinking it is 300MB. "Modern" IDE drives apparently don't care so much about the BIOS configuration as long as they have enough sectors to support the size configured.
 
You can also use a DDO (dynamic drive overlay), which allows for large hard disk support on older systems. With a 386 installed, even modernish DDOs should be fine.

I second the larger-than-seen approach, though. I've used this method with CF cards in IDE adapters with no problems. I plan on testing it with the industrial flash modules I have on-order, as soon as they arrive.
 
mark66j said:
"Modern" IDE drives apparently don't care so much about the BIOS configuration as long as they have enough sectors to support the size configured.
Click to expand...

Not just modern... all ATA drives do sector translation at the hardware level, so it really doesn't matter whether the BIOS drive type you select matches the drive's specified parameters, just as long as the BIOS doesn't think it has more total capacity than the drive actually has (cylinders × heads × sectors per track × 512 = total formatted capacity in bytes).
 
The original hard disk has failed, so i'll have to use a more modern one, but I have no idea even how to set the machine up to read/boot from its original letalone a replacement.
Click to expand...

From what you say, I am far from convinced that there is anything wrong with the original hard disk. What exactly is the drive? If it is an older one (MFM/RLL) then a bootable DOS disk with debug, fdisk, and format, is all the "setup disk" you need. In case you didn't know, these old drives need to be low level formatted (using debug) just as a matter of maintenance. :)
 
It's possible that the CMOS battery is flat and the machine has just forgotten what type of hard drive is connected. It doesn't do any kind of auto-detection, so it can't find a drive to boot.

The setup disk will let you change all the BIOS settings, so you can reset the hard drive type to whatever it's supposed to be.
 
If the hard drive is original to the machine, it probably has a label with the "drive type" on it. In any case, with these Compaqs you definitely need the setup disk to change the bios settings. If you can't find an image online of this, I can post the files.
 
Ole Juul said:
From what you say, I am far from convinced that there is anything wrong with the original hard disk. What exactly is the drive? If it is an older one (MFM/RLL) then a bootable DOS disk with debug, fdisk, and format, is all the "setup disk" you need. In case you didn't know, these old drives need to be low level formatted (using debug) just as a matter of maintenance. :)
Click to expand...

It's definitely dead, my friend tested it and it was full of bad sectors, and besides which he put it in the bin so it's out of the question unfortunately.

The CMOS battery is definitely flat, and I have ordered a new dallas cmos chip so that will be fixed when I can get it. I'm still waiting on some 5.25" floppies to put the setup disk on.
 
Neosodium said:
It's definitely dead, my friend tested it and it was full of bad sectors, and besides which he put it in the bin so it's out of the question unfortunately.

The CMOS battery is definitely flat, and I have ordered a new dallas cmos chip so that will be fixed when I can get it. I'm still waiting on some 5.25" floppies to put the setup disk on.
Click to expand...

Bad sectors is what's to be expected if it needs a low level format. A LLF locks out the bad sectors, just like on a new one. That's how those work and people used to do it as regular maintenance. Anyway, I don't want to flog a dead horse. :) I don't even know what kind of drive it had/needs. I guess I missed it and am making assumptions. :) What's the interface?
 
yeah there's a good possibility that drive was okay. shame if it is and got tossed. good MFM drives are getting very, very rare.
 
Okay, I have got some 5.25" floppy disks now, and the floppy that came with the portable was an installer for "IBM PC DOS 2.1" which I managed to get booting from another floppy. I still need a new clock chip (the one I ordered *still* hasn't arrived despite allegedly being sent first class) and the diagnostic diskette. Currently can't get any software on DOS because I have no way to get it on 5.25" floppies (looking for a drive still) but progress is happening. Once I can get a clock chip and the diagnostic/bios disk I can start setting a hard disk up for it to boot from.
 
Neosodium said:
Or not?
Click to expand...

Sorry Neosodium, logins have been very sporadic as my internet had become useless (like vague usability of a couple of minutes, followed by half an hour of futility) so I haven't really been talking to anyone on the web.

You could pop over, I'm in most weekday afternoons and evenings, although it sounds like you're quite well sorted. I could also post you an RTC (real time clock, not road traffic collision!)
 
nige the hippy said:
Sorry Neosodium, logins have been very sporadic as my internet had become useless (like vague usability of a couple of minutes, followed by half an hour of futility) so I haven't really been talking to anyone on the web.

You could pop over, I'm in most weekday afternoons and evenings, although it sounds like you're quite well sorted. I could also post you an RTC (real time clock, not road traffic collision!)
Click to expand...

That sounds like a nuisance, could you PM or email me your phone num so I can get hold of you? It would probably be useful to visit if you have any old PC bits (still havent gotten the RTC chip delivered from MDS)
 
I finally recieved the new Dallas chip a few days ago, but I have now found I don't know where to get a digital copy of the CMOS setup diskette (I need this to allow a hard drive and to stop it complaining on startup)

Anyone know where to get one or have a copy?
 
You must log in or register to reply here.
Back
Top