I gave the board a try with a number of different ROMS including the supersoft diagnostic ROMs for the 5170. Nothing, blank screen and no POST card activity.
I tried both swapping each of the ROMS since I don't know which socket is for odd and even. The board currently has no RAM chips because I only have enough to populate one bank of 16 and I don't know which is bank 0.
That shouldn't be an issue for the diag ROM working or a normal ROM displaying something to the POST card.
I'm thinking there is probably a data or address line problem preventing valid ROM reads or maybe a dead CPU.
At this stage I'll set it aside until I'm more motivated to go over it with a logic probe.
I guess I should have held off on ordering the 40 x 41256 RAM's until I had it working.
Edit:
I did a quick probe around the ROMS. A1 is held low and /CE remains high even after a reset. I see plenty of activity on the data and the other address lines so I know the CPU is good at least.
Strangely A1 at the ROMS was low but A2 and A3 low and A1 normal at the slots. Then I discovered the 74LS612 memory mapper chip was quite hot, with that chip pulled I get normal activity again on A1,A2 and A3.
I've ordered a couple on ebay and will look at it again in a month or so when they arrive, hopefully that proves to be the only fault.
