From mboxrd@z Thu Jan  1 00:00:00 1970
From: bqt@update.uu.se (Johnny Billquist)
Date: Sat, 13 Dec 2003 02:56:25 +0100 (CET)
Subject: [pups] pdp11/73 memory
In-Reply-To: <20031212172335.GB3476@bcr10.uwaterloo.ca>
Message-ID: <Pine.LNX.4.21.0312130254520.7015-100000@Tempo.Update.UU.SE>

On Fri, 12 Dec 2003, David Evans wrote:

> On Fri, Dec 12, 2003 at 06:31:12PM +0200, Christos Papachristou wrote:
> >  
> > Is it possible to keep some
> > of the MicroVAX memory modules if they are below or equal to 4 megs?  
> 
>   No.  The uVAX memory requires special PMI stuff (carried over those
> ribbon cables) that the PDP-11 CPUs don't grok.  At least, that's
> what I've always been told.

And that's correct.

The 11/73 require Q-bus memory. The only VAX that used this is the
MicroVAX I.
If the 11/73 really is a disguised 11/83 CPU, you can use the 11/83 PMI
memory, which don't work the same way as the VAX PMI.

(PMI by the way stands for Private Memory Interconnect)

	Johnny

Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email: bqt at update.uu.se           ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol