dave343 wrote on 2016-06-16, 13:46:

I acquired a Compaq 386s/20n PC, 20MHz 386SX, 6MB, with a 85mb drive. Initially I kept getting a settings error on boot up and i […]
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I acquired a Compaq 386s/20n PC, 20MHz 386SX, 6MB, with a 85mb drive. Initially I kept getting a settings error on boot up and it wouldn't keep the bios settings, but that was due to the Dallas 1287 battery being dead. I fixed that issue last night by soldering on a 2032 battery to pins 16 & 20 as per some helpful guides I found. Now I'm getting a 1782 Disk Controller Error on start up. I'm not sure if it's related, but the Compaq BIOS only allows you to select from a list of about 62 Hard Drive Types. Type 47, which I think is usually Custom? does not allow for modification. The 85mb hard drive that was installed and looks to be original, has Heads, Cylinders, and Sectors which don't match any of the HDD Types to choose from. There is a 84.3mb Type (I think 52) but it's sectors etc... are way off. I've also tried a 1.6gb drive and just choose a HDD Type that was 500mb.

So here is where it gets weird. Out of maybe 10 power cycles / reboots, twice it booted up without the Disk Controller error, and on that second time I was able to install Dos 5.0 on the 1.6gb (Type 42 for 510mb). After Dos wanted to reboot however, I got the Disk Controller Error again.
The IDE Cable looks undamaged, and the inside of the PC was very clean. The 1.6GB Drive and the 85mb original drive I can confirm are good drives as I tested them in a 486 system. Is there something else I can check? It would seem like a bad connection somewhere, because I'm crossing my fingers the on-board controller isn't dead/dying... The Floppy Drive detects fine and works good. The IDE connector is standard on the HDD drive but it plugs into a weird connector on the board side.

I haven't taken a pic of my own but here's one that's identical.

Did you manage to solve the problem ? I have Compaq 386/20e and almost the same issue - after exchange of clock battery I can not boot my PC from HD with same mistakes - 1790 disc 0 error and 1782 disc controller failure. Before battery failure my PC was running absolutely perfect.

Need to say, 1790 and 1782 errors were really bad sign for my HDD, and it finally crashed.

After it was replaced to Conner CFS420A, I got PC back to work, have installed original MS-DOS 5.0, and now my task is to get it communicating with Masspectrometer ITS40 through PCI card and IEEE488 port ( by default it is IRQ7 port, according to system description ). My question is - should it communicate with my device if no other hardware changes were made other then HDD and CMOS battery change ? Or still I need to have special PCI card drivers ?
On the picture you can see two PCI cards - network card on the right and IEEE488 on left.
Thanks for reading and you ideas.

Klimanski wrote on 2021-03-23, 09:07:

Need to say, 1790 and 1782 errors were really bad sign for my HDD, and it finally crashed. […]
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Need to say, 1790 and 1782 errors were really bad sign for my HDD, and it finally crashed.

After it was replaced to Conner CFS420A, I got PC back to work, have installed original MS-DOS 5.0, and now my task is to get it communicating with Masspectrometer ITS40 through PCI card and IEEE488 port ( by default it is IRQ7 port, according to system description ). My question is - should it communicate with my device if no other hardware changes were made other then HDD and CMOS battery change ? Or still I need to have special PCI card drivers ?
On the picture you can see two PCI cards - network card on the right and IEEE488 on left.
Thanks for reading and you ideas.

This should be a seperate thread, not a necrobumped one, and those two cards are ISA, not PCI.

Thanks for letting know, that it is ISA. I have opened new thread, hope at the right place 😀

Klimanski wrote on 2021-02-16, 12:02:

dave343 wrote on 2016-06-16, 13:46:

I acquired a Compaq 386s/20n PC, 20MHz 386SX, 6MB, with a 85mb drive. Initially I kept getting a settings error on boot up and i […]
Show full quote

I acquired a Compaq 386s/20n PC, 20MHz 386SX, 6MB, with a 85mb drive. Initially I kept getting a settings error on boot up and it wouldn't keep the bios settings, but that was due to the Dallas 1287 battery being dead. I fixed that issue last night by soldering on a 2032 battery to pins 16 & 20 as per some helpful guides I found. Now I'm getting a 1782 Disk Controller Error on start up. I'm not sure if it's related, but the Compaq BIOS only allows you to select from a list of about 62 Hard Drive Types. Type 47, which I think is usually Custom? does not allow for modification. The 85mb hard drive that was installed and looks to be original, has Heads, Cylinders, and Sectors which don't match any of the HDD Types to choose from. There is a 84.3mb Type (I think 52) but it's sectors etc... are way off. I've also tried a 1.6gb drive and just choose a HDD Type that was 500mb.

So here is where it gets weird. Out of maybe 10 power cycles / reboots, twice it booted up without the Disk Controller error, and on that second time I was able to install Dos 5.0 on the 1.6gb (Type 42 for 510mb). After Dos wanted to reboot however, I got the Disk Controller Error again.
The IDE Cable looks undamaged, and the inside of the PC was very clean. The 1.6GB Drive and the 85mb original drive I can confirm are good drives as I tested them in a 486 system. Is there something else I can check? It would seem like a bad connection somewhere, because I'm crossing my fingers the on-board controller isn't dead/dying... The Floppy Drive detects fine and works good. The IDE connector is standard on the HDD drive but it plugs into a weird connector on the board side.

I haven't taken a pic of my own but here's one that's identical.

Did you manage to solve the problem ? I have Compaq 386/20e and almost the same issue - after exchange of clock battery I can not boot my PC from HD with same mistakes - 1790 disc 0 error and 1782 disc controller failure. Before battery failure my PC was running absolutely perfect.

I don't remember, but I also no longer have the PC. I just built a custom AM386/DX 40, 8MB, 256MB CF Card PC. Running Dos 5.0.

When this happens, one have to confirm that hard drive is dead before blaming the vintage computer. What's the reason for not keeping the Compaq?

I use newer PATA hard drive on hand of any size and manually choose the type in CMOS set up screen, I used the 500MB range on example 300GB hard drive, it will be seen as 500MB and will work with DOS and Windows 3.x.

Cheers,

dave343 wrote on 2021-04-10, 15:30:

I don't remember, but I also no longer have the PC. I just built a custom AM386/DX 40, 8MB, 256MB CF Card PC. Running Dos 5.0.

pentiumspeed wrote on 2021-04-10, 19:26:

When this happens, one have to confirm that hard drive is dead before blaming the vintage computer. What's the reason for not keeping the Compaq?

I use newer PATA hard drive on hand of any size and manually choose the type in CMOS set up screen, I used the 500MB range on example 300GB hard drive, it will be seen as 500MB and will work with DOS and Windows 3.x.

Cheers,

In my case, reason was really HDD - it dead together with battery. After I have replaced both, PC works OK , just I need to restore lost BIOS settings.

I was replying to Dave343's.

Cheers,