" wrote:

On Mar 21, 3:13 pm, Gary Tait wrote:
" wrote groups.com:

The 486 however has an on board IDE
controller which it now occurs eto me perhaps should have been
disabled. So now when I try to boot it counts the ram and displays a
cache message but I get this message that reads : "last boot failed,
use default configuration"

Disable the onbard IDE, the BIOS likely will see the MFM card.

This one guy is telling me that because my original controller was a
WD 300 operating my Seagate drives and the drives were possibly set up
with that controller, that controller is the only one that I can use
to get into my drives. He says that even the Seagate controller which
I borrowed from someone and i have been trying to use will not work.
Does this sound reasonable?


There was no standard for 8 bit HD controllers, even with the same
manufacturer. 16 bit HD controllers were more compatible, as long as
they were for the same type of drive. You had MFM, RLL, SCSI, and a few
other interfaces/formats. The standard MFM or RLL card supported a pair
of drives and all you had to do was pair it up with the right class of
card. One BIG problem was that some 386 and most 486 motherboards were
too fast to support the MFM or RLL controller cards. The fact that the
motherboard has an IDE port makes it very likely that it can not support
a MFM or RLL drive, unless you set the CPU speed as low as possible.
Even then, it may be too fast. I keep a couple old 286 computers around
to transfer the data to IDE drives, and can be used in faster
computers. The early IDE controller cards gave you a choice of several
base addresses so you could add them to older computers without a
conflict. There was a great website called "The Ref (tm)" with a lot of
mirrored sites, but I can't find any of them that still exist.

Another reference is the "Pocket PC Ref" from Sequoia publishing:
http://www.google.com/search?num=100&hl=en&newwindow=1&rls=GWYA%2CGWYA%3 A2006-31%2CGWYA%3Aen&q=%22Pocket+PC+Ref%22&btnG=Search
that has a LOT of data on older drives. You have to know the number of
cylinders, heads and sectors to set up a MFM drive. There were a few
standard sizes in the BIOS, but most drives required a custom
configuration.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida