Yay! I'm up - it's working! Thanks all.
- No need for scope or anything. Just started probing cart lines while the C64 was on and the cart attached. About the only thing that looked reasonable were the clks and the nmi\.
- EXROM\ and GAME\ were both negated. I didn't check, but I assume the CROM was selected at this time, causing the black screen.
- Probed around the board while powered up but disconnected from the C64. Reviewed CUPL file. GAME\ and EXROM\ should both be asserted.
- Decided the CPLD programming must be bad because the logic to assert these lines is very straightforward.
- Reprogrammed the CPLD, same result.
- Recompiled the cupl file -> jedec again, selected Device Dependent Compile, got a file much smaller this time.
- Programmed this into the board, installed in my C64 (reloaded).
- Black/White "demo bars" - Well at least the computer was running code from the cart.
- Decided to try a different C64. Bam! Right into the chess board.
Here is a good JEDEC file, if a moderator could remove the one above, that would be good for the next person that attempts to build this.
The cart does NOT work in my C64 Reloaded board. (mark 1)
The cart DOES work in my Ultimate 64, a C128, and an early C64 with the reduced video output DIN connector.