Running an SE/30 rom (which has a bit more of a rigorous ram test) and the system fails almost immediately.
So yeah. It’s ram. Or RAM circuitry related
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Well goodish news - the VRAM is running. Doing tech step commands and checking the video ram forces the grey background to show up!
The only thing I can think of at the moment is that I may have made a schoolboy error. I placed 74LS components down for the muxes, rather than 74F components
Key difference is the speed of them - 74Fs are about twice as fast as 74LS parts
I mean I should have seen this. Without any ram installed the system doesn’t checkerboard - it only shows a simasimac (the default vram state)
You know it’s almost acting like I’ve only populated the wrong RAM bank.
Wait
So on an actual SE/30 - RASA signals go to Bank B and RASB goes to bank A.
Wonderful. Amazing. Brilliant. I totally didn’t get that backwards on my design.
