On Tue, 8 Sep 2020, Jules Richardson via cctalk wrote:
OK, it boots off a DOS 3.3 floppy if that floppy is inserted before it
attempts to boot from the hard disk. If I wait for it to do its "system file
not found" bit, followed by a subsequent prompt to insert boot media and
press a key, it attempts to access the floppy drive but then goes off into
la-la land. Odd.
How large is the drive?
If it is over 32MB, then try to find DOS 3.31 or newer.
MY preference is MS-DOS 6.22
But anyway, taking the successful floppy boot route, I can certainly access
the hard disk in terms of bringing up directory listings and TYPEing files to
the display. So far, attempts to run anything from the drive just result in a
lock-up (keyboard immediately unresponsive, hard reset required). There
appear to be DOS utils on the drive, and command.com, but I've not checked
for hidden system files yet. fdisk shows the partition as active.
Date and time of Command.com and any other DOS files will identify the
version number.
DIR /A or
DIR /A:H
will let you see the hidden files (presumably IO.SYS and MSDOS.SYS; PC-DOS
had IBMBIO.COM and IBMDOS.COM instead)
Can you COPY files from the HDD to floppy?
Being able to access contents of files, but not RUN them seems odd.
IF the DOS on the floppy misunderstands the partition table, then root
directory might look OK, but sub-directories might not be where it thinks
they are, . . .
Got an IBM "Advanced Diagnostics" floppy to try?
No, but I see that the minuszerodegrees site has an image, so I'll write that
out and see what happens.
NOT a big deal. It's merely the only method directly from IBM for doing
low level format.
In most cases, Speedstor is more useful for LLF.
Looking at the drive contents, incidentally, I didn't see anything that
explains (or interacts with) that unusual video hardware - it basically just
holds DOS and a bunch of documents written by the original owner. Maybe they
got suckered into buying this fancy graphics hardware without having any
actual need for it, and then of course EGA and VGA came along and rendered it
obsolete anyway.
It is probably completely CGA compatible, unless you invoke of of its
other modes.
The ROM on the video card may be a BIOS extension, in which case access to
extended modes may be handled internally in various programs. For
instance Windows 3.x, PC PAint, Pagemaker, and Xerox Ventura let you
configure for a variety of video hardware.
Otherwise, check to see if CONFIG.SYS has DEVICE commands to load any
device drivers, usually .SYS, although sometimes .COM
XT controllers tended to NOT be interchangeable, even between various OEMs
of Xebec!
Yes - something that people often seem to forget, too. I've run into that
quite often, where someone will hang onto an old drive because of the
contents, but they'll dump the controller that it was formatted against.
It always seemed counter-intuitive that makers of HDD hardware for XT
didn't slavishly mimic IBM's XT HDD. And especially counter-intuitive
that different vendor Xebec controllers didn't always interchange.
--
Grumpy Ol' Fred ci...@xenosoft.com
