On 2017-03-07 02:21, Tim Stark wrote:
Hmm, interesting. K.scsi is not mentioned in my HSC50/70 docs. Does anyone
have any docs contains K.scsi tech info?
I don't. I have no technical information on any of the modules. But I do
know that your HSC90 documentation have a bit of information about the
upgrade to be able to use SCSI. But it's mostly about how to install the
stuff.
Johnny
Thanks again,
Tim
-----Original Message-----
From: Simh [mailto:simh-boun...@trailing-edge.com] On Behalf Of Johnny Billquist
Sent: Monday, March 6, 2017 6:47 PM
To: simh@trailing-edge.com
Subject: Re: [Simh] CI750 tech docs and VAX firmware
On 2017-03-06 15:03, Timothe Litt wrote:
There were also HSC40 & hsc60.
Right. Pretty similar to all the others. The differences (as far as I can
remember) were mostly on the number of SDI/STI ports available, and the amount
of cache in the machine.
The differences in the hsc family members were the processor, cache,
load device, number of channels, and maximum number of ports. Some
models were field-upgradable. Also, later models supported
(reluctantly) the K.scsi module, which allowed the HSC to serve SCSI
disks and tapes. (SCSI was carefully analyzed & found to have
reliability/data integrity issues; DEC's answer was DSSI. Rather like
Beta & VHS - "good enough, but cheaper" won.)
Right. However, to use the K.scsi, you actually needed to upgrade. The
HSC90 with the capability to use K.scsi was the HSC95. I don't think the
HSC70 could at all. The 40 and 60 could, I think, but I wonder if they then
were renamed 45 and 65. I think I still have some documentation somewhere, but
it would take some digging to find this.
At some point, support for 18-bit disks (576 byte sectors) was dropped.
The HSC50 definitely had it; the HSC90 did not. I'm unsure about the HSC70.
Unless I remember totally wrong, only the HSC50 could do 576 byte sectors. It
was dropped in a pretty early version of CRONIC, before support for any other
HSC controller existed.
Johnny
_______________________________________________
Simh mailing list
Simh@trailing-edge.com
http://mailman.trailing-edge.com/mailman/listinfo/simh
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: b...@softjar.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
_______________________________________________
Simh mailing list
Simh@trailing-edge.com
http://mailman.trailing-edge.com/mailman/listinfo/simh
