J Blaser wrote:
> Here is my card cage configuration:
> 
> 1- M7620-BA : KA650-BA uVAX III CPU ->
> 2- M7621-AP : MS650-AA 8MB RAM      ->
> 3- M9047 : bus grant                | (empty)
> 4- M7516 : DELQA-M Ethernet         | M9047 : bus grant
> 5- M7169 : QDSS Base                ->
> 6- M7168 : QDSS 4-plane             ->
> 7- M7546 : TQK50-AA TK50 cntlr      | M9047 : RQDX3 MFM/Floppy cntlr
> 8- (empty)                          | (empty)

> This system has a backplane with slots 1-3 as Q/CD and slots 4-8 as
> Q/Q, so that gap in slot 3CD shouldn't matter (and doesn't).

Over the years, my experience has been that quite a few oddball
I/O problems have been down to a broken grant chain. You seem
to be the exception here :-)

> This is a uVAX II so, sadly, no SHOW DEVICE command is recognized.

It's a MicroVAX III not a II. If you have a really early rev of the
console, then it's basically a slightly altered uVAX II boot ROM
and only has the uVAX II commands. I used to have an intel hex dump
of the latest boot rom around, but I cannot find it right now. In
the past I've swapped a KA650 into a system in place of a KA630 
just because of the additional diagnostic capabilities!

> However, based on comments from vax9000 and others, I think that I
> might have a short between boards somewhere.  This is what I'll check
> for next.  And then check to see that there aren't any lost jumpers,
> or other CSR/vector misconfigurations.

That's a distinct possibility, should be easy enough to track down
just by carfeully rearranging the cables ... fairly straightforward
in a BA123 style box, somewhat trickier in a BA23 box!

Antonio
arcarlini@iee.org