The Last of The Line - test-drb@ccmp.vtda.org

14 May 2007

Ah Ha ... Thanks and the memory card would be a ????

Rod

-----Original Message-----
From: cctech-bounces at classiccmp.org
[mailto:cctech-bounces at classiccmp.org] On Behalf Of Roger Ivie
Sent: 14 May 2007 21:02
To: General Discussion: On-Topic Posts Only
Subject: RE: The Last of The Line

On Mon, 14 May 2007, Rod Smallwood wrote:
...
   When preserving something you go for the best example
you can find.
 Even so in this case there was no choice involved. I want to keep as 
 original as I can a a PDP-11 from the era when I was working with them.
...
  Speed is not an issue and a slower (but working)DEC
KDJ11 board would 
 satisfy my criteria for originality. 
I've never met an 11/94, so I'm no expert. My understanding of the
situation was the 11/94 was built when it became possible to put all of
the memory on the CPU board.

The 11/84 used a CPU board without memory. The memory was in the slots
between the CPU board and the UNIBUS adapter, communicating with the CPU
board using a private memory interconnect protocol. I don't recall
whether there was an additional ribbon cable across the top, like the
MicroVAX II.

I'm pretty certain (but, have been wrong before) that the KDJ11-BB would
be the 11/83 or 11/84 CPU; they used the same CPU board, differing in
the backplane and whether the UNIBUS adapter was present.
--
roger ivie
rivie at ridgenet.net