Re: Non-working Commodore PET 3016
Lovely. Now, look at the rest of the CPU address lines A1-A15 going upwards in order. I'm not going to do pin numbers (and mess them up) any more, you are obviously able to work these out for yourself. (Where there is scope for confusion I will still state pin numbers and hopefully get them right as well).
What you should see is the same kind of waveform but with the frequency halving / length of the high pulse / length of the low gap between pulses doubling each time you move to a higher address line. You'll probably have to wind down the horizontal speed each time you move up a couple of lines as the length of a pulse would soon be wider than your trace otherwise.
Once you've verified that all the CPU address lines have activity a quick verification check would be to measure the frequency on each of A0-A15 and you should find that the frequency halves each time you move up an address line. (Bear in mind that quirk of your frequency meter, where it needs a half-supply ground, if you try this).
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