Is this the Async clock module? (where you looking at the PDF from spies or do yo have a schematic?)
2 identical signatures for the 9010A? we've got a collection of a paultry few. I did run across one the otherday but I'm pretty confident it was a typo.
Alex Yeckley are you reading?
If I understand the question, I'm being asked if I know of any duplicate checksums or sigs? Yes I do - it was either Missile Command or Lunar Lander between different code revs, I don't recall the details. My theory was that Atari wanted to mix and match code revs of certain ROMs without altering the self-test (and hence requiring owners to swap more ROMs than was absolutely necessary). I think they probably just added a "catch-up" byte at the top of affected ROM to force the checksum/sig to whatever value they wanted. Maybe it was Asteroids - I have it written down, but not in any kind of format that I can search on. I haven't encountered any situations where - for example - a Pac Man checksum/sig just happened to be the same as a Sprint 2 checksum/sig. Alex ---- http://www.elektronforge.com ayeckley@elektronforge.com