🚀 go-pugleaf

In article <1993Jan6.102059.29154@lugb.latrobe.edu.au>, cchd@lucifer.latrobe.edu.au (Huw Davies) writes:
> As part of a project I'm involved with at work to use a 780 and 785 as
> backend processors for our soon to arrive Alpha system I have ended up
> with the two VAX systems sharing one BA11 (the other BA11 was 110V and
> made nice white smoke when used at 240V :-).
> 
> The two systems are up and running, but there is one little problem
> (there's always one little problem :-). Unless both VAX processors are
> powered up, the devices in the BA11 appear invisible to the VAX
> that's running. From my understanding of the wiring of the parts of the
> BA11 backplane, the only signals passed through relate to power supply,
> not logic. Can anyone shed any light on this?
> -- 

ACLOW and DCLOW The devices SHOULD refuse all discourse till both are high.
Either CPU down will pull the lines LOW, -> powerfail, hence devices will crawl
off to NewZealand and sulk.

I assume you are using two lots of DDs in one case, so a little diode or two
in the right places should fixit.

The other answer of course, is make sure both vaxen are sucking. ( 240v that is
:-) what do you expect posting this to .pdp-11 ) Guess its not the omega.

Got a spare ba if you want it...

~Paul