Qbus and Q/CD jumpers

From: Chuck McManis <cmcmanis_at_mcmanis.com>
Date: Mon Dec 13 02:17:04 1999

At 11:31 PM 12/12/99 -0800, John Lawson wrote:
> Chuck, I have the DHV11 Technical Manual here, if that would be of
>any help. I can transcribe relevant parts, or send it to you for a
>loaner...


The relevant bits in this case would be the description of the jumpers "W1"
and "W2" which control the shorting of the bus grant pins on the C/D fingers.

One way to answer the question is this:
         Does the DHV11 with its bus grant jumpers installed, interfere
with memory
         connected to a KA650 VAX processor?

I've got a BA213 chassis which is Q/CD for all of its slots. Interestingly,
from another BA213 I pulled a CXY08 (M3119) and it had its jumpers
installed. That would suggest that they don't interfere with the VAX memory
subsystem.

When I install the DHV11 "ahead" of the KFQSA DSSI controller, the
operating system periodically gets bogus data in its memory pages. I'll
probably go ahead and cut the jumpers as an experiment, but this isn't
"knowing"

--Chuck
Received on Mon Dec 13 1999 - 02:17:04 GMT