Thanks for all of the discussion and testing in this thread.
We resolved our issues yesterday and now have a working Dig Dug 2 boardset.
The two issues that prevented our boardset from fully working as a Dig Dug 2 were:
- 4C has to be 82C129, not 82S126
- Awful timing, but pin 12 was stuck high on the adjacent 74LS158, so it was replaced
Once these two changes were made, the boardset worked as Dig Dug 2.
As part of the testing, we also confirmed that 5K and 3M do work with 82S126, but 3M also worked with a 82S129. JROK mentioned previously in the thread that 3M has to be a 82S129, but we found an 82S126 also worked. Maybe a quirk, but there it is...
Hopefully, the above information, combined with the other testing and information posted in this thread, flushes out the documentation for this conversion. Again, thanks to everyone for this great thread. Looks like all that remains is confirming how the second Player button works, presumably on two different boardsets (Midway vs. Namco?).
Scott C.