On 10/2/17 10:13 AM, Jules Richardson via cctech wrote:
On 10/02/2017 08:29 AM, allison via cctech wrote:
On 10/2/17 8:22 AM, Jules Richardson via cctech wrote:
On 10/02/2017 01:46 AM, Alan Perry via cctech wrote:
There was a call to form the CAM (Common Access Method) Committee
of X3T9.2
(SCSI-2) on 30 Sept 1988 and they first met on 19 Oct 1988. The
primary
goal was to come up with a SCSI subset to facilitate it support in
multiple
OSs and BIOS on PCs. At the first meeting, two items mentioned in the
minutes seem relevant. 1. Jim McGrath of Quantum was interested in
embedding SCSI in the drive without a physical SCSI bus and described
problems with reference to the PC/AT.
So in effect the IDE was a minimal interface that would interface to the
computer bus
with no more than buffering.
True, I suppose the command structure was more complex with SCSI. It's
a shame though, it would have been nice if SCSI had been the PC
standard, what with the large number of devices available, more
flexibility, and performance potential.
It was/is widely used in PCs. It put Adaptec on the map. Servers and
high end systems
commonly used it especially for early shadow and RAID systems.
Early SCSI disks
were MFM drives with Adaptec or Xybec host boards (SCSI to MFM, local
cpu
was Z80 on the adaptor).
Xebec... but yeah, and I forgot that they used a Z80 (I was thinking
it was some Intel 80xx thing).
Later versions of bridge boards had the 8088 or 80188 16bitter.
I don't know if Xebec actually made a SCSI one, I think they may all
have been SASI (at least the ones that I've used). I remember there
was a little schematic in the back of the manual for a suitable
controller.
Some were SASI and later firmware was SCSI... Only difference as I had
both.
Adaptec, Emulex and OMTI all made similar bridge boards... and there
were probably others, too.
Yes, them too.
Oddly the first VAX to use SCSI or SCSI like was uVAX-2000 as the extra
box with TK50 Tape
used that.
Allison
cheers
Jules
