Good timing. My current weekend project is constructing something similar to the the first third of Ben Eater's 6502 design (last weekend was the clock module plus some eccentricities).

It occurred to me that given the 6502's predictable clock cycle timings it should be possible to create a realtime disassembler using e.g. an Arduino Mega 2560+character lcd display attached to the 6502's address/data/etc pins.

Of course, this would only be useful in single-stepping/very slow clock speeds. Still, I think it could be useful in learning how the 6502 works.

Is there relevant prior work? I'm struggling with my google fu.