26 Feb
2013
26 Feb
'13
5:57 p.m.
cctalk-request at classiccmp.org wrote:
Subject:
Re: PDP-11 / Unibus: config info for Motorola Memory Systems MMS1117
MOS board?
From:
ard at p850ug1.demon.co.uk (Tony Duell)
Date:
Sun, 24 Feb 2013 19:37:05 +0000 (GMT)
To:
cctalk at classiccmp.org
I had a similar problem when I got my first PDP11 (a PDP11/45). The donor
had wanted to keep the memory that was used in it, he gave me what I
later discoveed to be a 32KW MUD board (actually, it could be populated
right up to 128KW, of course only 124K of those would be useable). I had
no idea how to set the swiches, or indeed, what sort of backplane wiring
I would need to use it .
This was logn before the days of the web. so there was no way to ask
others what to do.
And I got it working. I spent a few weeks tracing out the scheamtics of
the unknown board and figuring out just what all the switches and jumpers
did. A long job, sure, but IMHO worth it.
-tony
Wow. Do you recall how many layers the PCB had? I'd be interested in
seeing a sample scan of the
schematic you laboriously produced, just to get an idea of technique.
The web has certainly made hobbies like this unimaginably easier, if not
just possible at all.
- jS
Folks, I'm restoring an 11/34A. One of the
MOS memory boards it came
with is a circa 1979 Motorola model "MMS1117", variation "58 PC"
(64KWords / 18 bits / w/parity). Would like to know if anyone out
there has configuration information for this seemingly uncommon board?
It's a very high quality board and has socketed RAM, so it'd be
especially nice to be able to keep using it. It has 5 switch packs
(only 2 of which have markings) and at least a dozen jumpers.