Re: I found it! A very sorry looking MK14.
Well, I've spent the last few hours checking the address decoding.
I removed ROMs, RAMs, and CPU. Put wires from a breadboard micro to drive A11-A8 and WDS/RDS.
Wrote code to wiggle pins cyclicly at a few hundred Hz, and prodded my scope where the decodes should come out. They all looked OK. ( I didn't actually check the addresses, just that the CE pins wiggled up and down nicely. )
So it looks like ROMs and/or ROMs are faulty. I've got four 2111s, and swapping them in all combinations made no difference at all. Using 'old' ROMs gives a different wrong display.
Tomorrow I'll rig up a RAM tester, and a ROM dumper.
I'm assuming those of you with VI boards just plugged all the bits in and it worked straight off ?.
Cheers,
Buzby
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