So I've got two early IDE drives, stepper-based: ST-125A and ST-157A.
Trying to run them in a 386DX/40 with a pretty generic Acer IDE/FDC/LPT/2xCOM/GAME card.
I'm confident the testing gear is OK - no problems with newer IDE drives.
The problematic drives are probably also OK - I can access them without any problems when I boot from a diskette, Checkit 3.0 tests do pass as well.
But I can't boot off these early drives!
Boot PC DOS 2000 from a diskette, fdisk, format, sys, and sometimes even fdisk/mbr to be sure, then trying to boot from the HDD - it waits for some time, and then displays "Non-system disk or disk error..."
I thought the problem might be geometry-related, at this moment I'm working on the ST-125A - it's auto-detected as 404/4/26 (C/H/S), Seagate docs suggest using IBM AT DRIVE TYPE 6, ie. 615/4/17, I tried both settings, but the problem persists.
I even tried The Forbidden Thing, ie. low-level format, using HDINIT from Checkit 3.0 - with 404/4/26 mapping it immediately fails with BIOS ERROR, with 615/4/17 it formats OK, but after fdisk/format/sys I still can't boot off the HDD.
Must be some weird incompatibility, I probably should try it with another machine, preferably older than that, but don't have anything else up and ready.
Any other ideas?
Trying to run them in a 386DX/40 with a pretty generic Acer IDE/FDC/LPT/2xCOM/GAME card.
I'm confident the testing gear is OK - no problems with newer IDE drives.
The problematic drives are probably also OK - I can access them without any problems when I boot from a diskette, Checkit 3.0 tests do pass as well.
But I can't boot off these early drives!
Boot PC DOS 2000 from a diskette, fdisk, format, sys, and sometimes even fdisk/mbr to be sure, then trying to boot from the HDD - it waits for some time, and then displays "Non-system disk or disk error..."
I thought the problem might be geometry-related, at this moment I'm working on the ST-125A - it's auto-detected as 404/4/26 (C/H/S), Seagate docs suggest using IBM AT DRIVE TYPE 6, ie. 615/4/17, I tried both settings, but the problem persists.
I even tried The Forbidden Thing, ie. low-level format, using HDINIT from Checkit 3.0 - with 404/4/26 mapping it immediately fails with BIOS ERROR, with 615/4/17 it formats OK, but after fdisk/format/sys I still can't boot off the HDD.
Must be some weird incompatibility, I probably should try it with another machine, preferably older than that, but don't have anything else up and ready.
Any other ideas?