10 Nov
2007
10 Nov
'07
1:51 p.m.
On 10 Nov 2007 at 15:24, Roy J. Tellason wrote:
Just lookingat the picture in that file I retrieved
makes me want to play with
that thing a bit. :-) I think, though, that instead of the 2 5.25"
drives I was originally intending to use with it (and which are buried
somewhere in storage at this point, I have no idea where), I'd like to
maybe have a go at interfacing a 3.5" drive to it. And maybe one of
the "smaller" (2G?) SCSI drives I have around here. Think that's possible?
Certainly the SCSI drive is possible, given the interface on the BBII
(Doesn't have a SASI-ready interface or two already?) Not wide-SCSI,
but certainly 8-bit SCSI. Your biggest problem is how to deal with
2GB efficiently with CP/M-80.
3.5" floppy is easy, but a 3.5" PATA drive is more problematical,
given the 16-bit interface for data. Of course, one could throw away
half the data or even treat the drive as two units to accommodate 8-
bit transfers.
Best I can remember, the code did a bunch of 16-bit
math that
seemed to implement some kind of a polynomial (just a bit beyond me
when I read it) and ran this over the contents of the EPROM,
looking for a zero result.
Could even be XORing the contents with a LFSR. Hard to say without
seeing it.
Cheers,
Chuck