I'm trying to use a tqrom to make a super mario 2 japan, but I've been having a hard time with the pinout. TQROM has a 28 pin CHR rom and 28 pin PRG rom, so i figured they match up with a 28 pin 27c512. The cart also has CHR ram and selects between using ether the rom or ram depending on pin 22 from what I've read. I grounded pin 22, but only get a black screen when trying to start the game.
Any help or advice would be appreciated, thanks!
Any help or advice would be appreciated, thanks!