18 May
2016
18 May
'16
8:33 p.m.
From: Ed Groenenberg
After hooking up the PMK05 to the unibus, the machine
was powered up
with the memory card, and the 'NPG' led was on.
Oh, that's truly wierd. Most memory cards don't even connect to any of the
bus request/grant lines - they often have short loopbacks from each 'grant
in' pin to 'grant out' - not sure about NPG because canonically, that is
jumpered through on the backplane.
A couple of things to check: First, does that memory even have traces
connected to the NPR/NPG-in/NPG-out pins? Second, does a different, known
working card, provoke any problems in that slot? (E.g. your serial interface
card?) I'm wondering if the problem is the slot, not the card.
Noel