11 May
2007
11 May
'07
9:29 p.m.
On 11 May 2007 at 19:59, jim wrote:
MSC if I recall correctly morphed into Xebec, who was
one of the first
if not the first supplieres ot controllers to IBM for the XT.
I believe that's true. I remember going over to their "incubator"
offices off of Mathilda (IIRC) and talking with them about this
board. I think they also did tape controller work. As I mentioned,
I have the programming spec--it's a longhand-edited version of their
stock MSC-1000 controller docs. I have the feeling that they did
quite a few "custom" jobs back then, mostly modifying the host-to-
controller part to order. Note the many empty DIP positions on the
left (host) side of the controller. Also not that there are 2 20-
position drive connectors on either side of the 50-position connector
on the right side of the board. We didn't ask for the 2nd drive
capability and couldn't have used it anyway. Within 2 years, the
5.25" hard drives started making their appearance and we went to a
controller card using bipolar 8X300 logic that was the size of an S-
100 card. Things moved very fast back then.
Sometime between this unit and the XT controller, I think they went
to programmable bit-slice components for their controllers (8X300?
2901?). This one's interesting in that, with the exception of the
8291, it's all discrete logic; no big ROMs or LSI.
Cheers,
Chuck