When I select the "grey border" I can see a change on the screen, though not in the form of a border. It appears pixelated.Mustermann wrote: ↑Thu Jan 02, 2020 9:11 pm Hi Ien,
did you try out "grey border" jumper. Even if Processor is in reset state this should give a grey output, so shift register and things around that can be tested.
If reset goes to high(check if it does) there should be some data seen in D0-D7.
Next you may pull ram and eprom out of the board and pull each data line to ground using a separate resistor per line(something between 1k and 10k).
So CPU may execute NOP operations. Signals on M1, MREQ and RFSH are expected to be visible.
Best regards,
Max
I am getting MREQ and RFSH signals. Also I can see data on D0/D1/D2 lines.. (I ran out of inputs)