Jerome H. Fine jhfinedp3k at compsys.to
Fri Jun 3 10:43:19 CDT 2016

 >Rod Smallwood wrote:

> [Snip]
> 4.  I have what I believed is a working 11/83 in my computer room
> 5 . I'm going to try my processor in there and yes I know about PMI 
> and  the backplane.

Just a bit of information from what I seem to remember - I hope
the information is correct.

The M8190-BF board I have supports:
(a) PMI memory placed ABOVE the CPU
(b) Non-PMI memory placed BELOW the CPU (I never
     attempted to place non-PMI memory ABOVE the
(c)  When the PMI memory was placed into the backplane
       BELOW the CPU, then the memory would act as
      normal non-PMI memory.

Under RT-11, the command:


will conclude that the following CPU is present:

(a)  PDP-11/83
(b)  PDP-11/73
(c)  PDP-11/73

So other than when PMI memory is placed BELOW the CPU
as in (c) and it therefore takes longer to access the memory, I don't
think the question of PMI memory will really make any difference.

Jerome Fine

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