Continuing PDP11 saga

From: Tom Leffingwell <>
Date: Thu Jan 10 22:14:29 2002

        I think you're right. I borrowed a DZQ11 board from a friend, and
I was able to set it to 770400. It returns 000000, but before it was in
there, it would just give a ?, so I presumed I had the address set
correctly. I tried to boot my program, and it gets right to the end of
loading the program, and hangs, although the run light stays on. If I
halt the system at this point, is there anything useful I can look at? I
suppose if nothing else, I've learned that the program does indeed check
for the presence of this module, and that I won't be able to fake it,
unless there's some I'm missing here.

        Come to think of it, I left the vector address alone (I think at
300). Should I have changed that, too, or will it not make a difference
since that board won't respond the same as the ADV11 anyway?

        Btw, the modules in the system will respond to both 18 and 22-bit
addresses. Does that mean I'm 22-bit?

        Unfortunately, I'll have to cough up $350 for a half-broken
ADV11-C, or a $750 for a working one, which I really don't want to do. I
don't suppose anyone on this list has an ADV11-C (functional,
half-functional, or not at all functional) that they wish to part with? :)


On Thu, 10 Jan 2002, Pete Turnbull wrote:

> Ouch! Sorry, I can't think of anything else offhand. Besides, if the
> software is checking for the presence of the board, it might write some
> initialisation value to it and try to read its status back. That would
> most likely fail if you had the wrong device at that address.
> --
> Pete Peter Turnbull
> Network Manager
> University of York
Received on Thu Jan 10 2002 - 22:14:29 GMT

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