On 2015-05-01 02:41, Johnny Billquist wrote:
On 2015-05-01 02:03, Timothe Litt wrote:
On 30-Apr-15 19:13, Cory Smelosky wrote:
On Thu, 30 Apr 2015, Timothe Litt wrote:
In DEC, volume shadowing was first built into the HSC50 (a CI-based
disk/tape controller), released in the early 80s. Drives were the 14"
RA81 and follow-ons. The early design work was in the late 70s. The
TOPS20 announcement of the CI, CFS and clusters predated the VMS
announcement, to the great annoyance of the VMS crew, which had it
running internally but wasn't permitted to announce it. TOPS20 didn't
support volume shadowing. Neither did TOPS10, though it did support CI
disks and tapes (but not clusters) later. The CI/MSCP protocol layers
used common code in both OSs, similar to what was done with DECnet.
Host-based volume shadowing came considerably later.
So...were MSCP drives connected to the KL/KS over CI to an HSC50? I
saw MSCP drivers but couldn't figure out how they were attached. ;)
KL only (KLIPA = KL -> CI adapter). No CI adapter for the KS.
Of course, the curious mind, especially in the light of where this
thread started, then wonders if not the UDA-50 would be possible to use
on a KS...?
Hmm, that might fail on that the UDA-50 might not have been able to deal
with 576 byte sectors... I seem to remember you needed some specific
versions of CRONIC for the UDA-50 to use 576 byte block disks...?
Dammit. I need to fix my fingers. That last "UDA-50" should have read
"HSC-50".
Johnny
_______________________________________________
Simh mailing list
[email protected]
http://mailman.trailing-edge.com/mailman/listinfo/simh
