> This was in an IBM 5150 (original PC)? I'm
still confused. The 1410A is a
> bridge board that presents an MFM drive as a SASI (pre-SCSI) device. What
> SCSI bus adapter is that machine fitted with?
On Tue, 13 Oct 2015, Jules
Richardson wrote:
Indeed, that and the 5150's PSU wasn't capable
of running a hard drive. Could
have been upgraded, of course, but it just made me wonder if this isn't some
other IBM product with a similar model number, and not a 5150 at all.
The XT (5160), NOT THE PC (5150) had a hard drive. It also had a larger
power supply than the PC. The XT hard disk was controlled by a board made
by Xebec, and rebranded as IBM. I don't remember the board model
number. As part of the rebranding, they removed the configuration
switches, so that it was "hard-wired" for 10M drive.
It supported two drives.
By soldering in jumpers (a 4 pole DIP switch fit just fine), you could set
either of the two drives for 5M?, 10M (default NC), 16M? or 26M?. Other
sizes or geometries could, of course be set by software after booting.