On Sun, May 22, 2016 at 12:33 PM, tony duell <a...@p850ug1.demon.co.uk> wrote:
> Strictly the core backplanes are not Unibus backplanes. They have Unibus In > and Out connectors, but the slots are wired for the core memory board, > not Unibus boards (like SPCs -- Small Peripheral Controllers -- which is > what > you serial port is). > > > Basic Question #1 > > Do I need grant cards in *every* empty slot of the core backplane, > > including the end slots with the M920's? > > No. In fact in most cases it is wrong to put grant continuity cards in > there. > However in a lot of cases a special backplane (like your core memory > one) will have some spare slots (perhaps the core memory doesn't take > up all 9 slots). And DEC often (but not always) wired those so you could > put SPCs in there. In which case you will need grant continuity cards in > those > slots if you have nothing else in them. > > Tony, Are you saying remove all of the GC cards, just leave the slots blank? Here is a photo of what I have now: http://vintagecomputer.net/digital/pdp11-40/coreplanes_installed.jpg remove the gc cards from the core planes? I will read up on this more, just getting started. thanks. Bill