Continuing PDP11 saga

From: Tom Leffingwell <tom_at_sba.miami.edu>
Date: Wed Jan 9 08:12:06 2002

I tried taking an M8027 and setting its address to 170400, to make it look
like the ADV11-C. However, when typing that address before and after I
installed the board, at the _at_ prompt, it returned 177777. Also, the
DRV11, at 167770, does the same thing. The DRV11-B gives 000000 (at
772410), although at the CSR (772414) it gives 006800.

My printer card that I tried to use as a fake ADV11 has jumpers on pin 12
and pin 8, with the rest removed. Is this correct for setting it to
170400?

I noticed on the DRV11 card that it says jumper in = logic 0. That one
has one jumper on pin 12, which I assume gives it the proper address of
167770. This one appears unmodified from the factory.

Are my jumpers on the printer card the opposite of what they should
be? Is 177777 what is returned for a missing board? If I have the
jumpers reversed on the printer card, that would explain that situation,
but it doesn't explain the DRV11, unless its bad.

Any thoughts?

Thanks,

Tom
Received on Wed Jan 09 2002 - 08:12:06 GMT