21 Apr
1999
21 Apr
'99
12:35 p.m.
Hi, Tim - You're a wealth of obscure information, as always!
I picked up the unit mainly for the front panel, with the toggle switches,
etc., but also an extra power supply and backplane wouldn't hurt. I'll move
the panel to that old 11/23 box I bought, if you remember it. That box now
has two RX02s and RT-11 running on it. I added an DELQA over the weekend
and am planning to get the Kent TCP/IP package running on it. Then perhaps
I'll throw it on the net from here at work!
SERF hasn't been too good lately for computer stuff, even old PCs. It was
mostly furniture today with a bit of chem lab equipment.
I didn't see any drives, so these cards will go in the "stock" boxes in
case anyone else needs them, in the future.
For those not familiar with SERF, it's the "surplus equipment recycling
facility" at the University of British Columbia here in Vancouver. The only
place where I've found Qbus boards at five for a dollar.
Thanks for the info Tim,
Kevin
At 05:03 PM 21/04/99 -0400, you wrote:
==========================================================
Sgt. Kevin McQuiggin, Vancouver Police Department
E-Comm Project (604) 215-5095; Cell: (604) 868-0544
Email: mcquiggi(a)sfu.ca
They are made
by (apparently) USDC, model number 1101, revisions "01" and
"BG". The chips are marked circa 1982. They have a Z80, som EPROM, a
couple of PALs, and a 40 pin IDC header. They are half-height boards (
i.e. two sets of fingers). "LSI-11 Host Interface" is silk screened onto
the board under the part number.
Can anyone tell me what these are? They came out of an 11/23 box badged
11-DM4, althought the box is in the truck and I may have the DM$ slightly
incorrect.
USDC= U.S. Design Corporation. They're based in Maryland, not too far
from where I now live. They sold (among other things) disk subsystems.
The one you have emulates RK06/RK07 drives, and hooked (via the 40
pin connector) to an external box that had a hard drive (either a 5.25" MFM
or a 8" non-MFM) with electronics that converted the native
drive interface to the 40-pin interface. You might have seen the
appropriate drive boxes in my storage space in Surrey, if you remember
our trip there :-). They're 5.25" rack-width boxes, have black fronts with
a row of bar LED's that blink in a cylon patterm when running, and are about
25" deep - you ought to head back out to UBC and see if there are any
USDC boxes meeting this description there. I still have the drives and
the interfaces, but it's been years since I've powered them up.
The controller is 22-bit-Qbus capable, but the PDP-11 OS's only know of
Unibus RK06's/07's, so machines with more than 256kbytes of memory
generally had USDC patches made to the OS drivers so they knew how to
do DMA to high memory.
--
Tim Shoppa Email:
Trailing Edge Technology WWW: http://www.trailing-edge.com/
7328 Bradley Blvd Voice: 301-767-5917
Bethesda, MD, USA 20817 Fax: 301-767-5927