8 Jun
2006
8 Jun
'06
7:36 p.m.
Thanks to everyone who helped me figure this out. It can be confusing
sometimes when you think you've looked everywhere and it's still just in the
wrong place.
Unfortunately, after properly checking the NPG and BG lines for continuity,
I found that they are wired properly - I was hoping for something simple
like that :(
So now that I know those lines are solid, and I know the Power supply is
outputting what it's supposed to, where do I go from here?
Next thing I would do is to pull the M9302 terminator. A single-backplane
machine like you currently have will run without it (at least for
testing) if everything else is OK. And the M9302 will lock the Unibus (it
asserts SACK and won't release it) if a grant gets all the way to the
terminator (the normal reason for this is that the chain is open at some
point, but you've checked this).
After that, I'd better get out the 11/34 printset and suggest good places
to stick the 'scope probe...
-tony