20 May
2014
20 May
'14
2:31 p.m.
You're going to need an ISA IDE adapter with its
own BIOS to use with an
IDE drive or an IDE-to-CF card adapter (Promise made some of those).
Strictly you don't ened a BIOS extension. IDE drives were designed ot be
compatible wit hthe Western Digital controller in the original PC/AT. If
you can modify the dirve geometry tabel [1] then it will work with the
drivers in the BIOS ROMs.
[1] It is possible to ad a singel TTL IC to disable the normal ROMs for
the last 8K words and map in 8K EPROMs (2764 type) inserted in the spare
sockets on the motherboard. IIRC, the modification doens't even involve
any track cuts, there is a helpful shunt block you cna use to intercept
the ROM select signals.
FWIW, the machine I am typing thsi on has an IDE drive, a bus interdace
[2] with no BIOS extensions and the mod made to change the disk parameter
tables. So it certainly works.
-tony