PDP 11/45 Display register.

Gooijen H GOOI at oce.nl
Tue Apr 5 14:45:57 CDT 2005

  Well, let's try to give an answer.
The SWitch Register is what is says: *switch* register.
So you can read the switches from it, but writing to it is no use.
Don't shoot me if I am mistaken!  From memory, the address is 777570.

- Henk, PA8PDP.

-----Original Message-----
From: cctalk-bounces at classiccmp.org
To: Classic  computer list
Sent: 5-4-2005 21:33
Subject: PDP 11/45 Display register.


A quick question raised by my ongoing work....

Is it possible to write directly to the "display register" - the one
accessed by one position of the data switch. I think it should be at
location 777570, but I can't get data into it, either using deposit from
console, or moving data under program control.

Have I got a fault, or am I doing something wrong?



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