I'm finding it hard to track down issues in some games/programs. Output debug information so I can look into the problem after the fact.
I'm thinking as a starting point something like this:
8-bit output at 4x clock:
Where flag is: R/W,ANTIC_FETCH,ANTIC_REFRESH,NMI_N,IRQ_N
Then those with USB streaming scopes - or e.g. FX2s can capture the trace of post-analysis. We can build a validation tool vs some emulators perhaps.