On 4/24/2015 11:32 PM, Josh Dersch wrote:
While I was waiting for the Ridge's
disk to dump over a 9600bps serial
port, I finally got a chance to work
on my 11/34. Picked it up last summer
and it was in good shape but the power
supply was completely dead. I've
rebuilt the supply and last night I
worked out the last few kinks.
So at this point all voltages are
spot-on, the AC LO and DC LO signals
are high (these are active low,
right?) but I can't get the machine to
respond at all -- the "DC ON" and
"RUN" lights are lit up brightly, and
the "SR DISP," "BUS ERR," and "MAINT"
lights are glowing dimly. The status
register display is dark. The system
does not respond to any keypresses on
the panel.
I'm getting better with UNIBUS stuff
but I wanted to run this past you guys
before I whip out the debugging tools
and start tracing things. I've taken
it down to a pretty minimal
configuration, sans any memory or
other stuff. Here's what I have in
the main backplane (all others are
disconnected for the time being) from
right to left:
Slot 1: M7266 (CPU)
Slot 2: M7265 (CPU)
Slot 3: (AB) M9301 (bootstrap
terminator) / (CDEF) M7859 (front
panel board)
Slot 4: empty
Slot 5: empty
Slot 6: empty
Slot 7: empty
Slot 8: empty
Slot 9: (AB) M9302 (terminator)
The "empty" slots have Grant
Continuity boards installed and the
NPG jumpers on CB1-CB2 are all present
on the backplane. I've confirmed that
all the right voltages are making it
to the backplane (and I've cleaned up
those damned Molex connectors as well,
just to be sure). Is there anything
I'm missing? Anything I should try?
Does this failure mode sound familiar
at all?
Thanks as always,
Josh
J, try this first:
- test your M7859 KY11-LB console and a
ram board in maint mode direct access.
See the manual for the KY11 for how to
do this. Use maint mode #5 to check
your MS11 at select locations, per
installed boards eg. M7847 16K RAM,
M9301+M9302, M7959 console. Keep the
CPU out of it for now.
- J.