>But Bob, don't you need the memory selector chip? >Friendly Regards >Octavio Nogueira presumably you mean the MBC1 or MBC5 chip ? it's only a really simple address decoder. easily replaced with standard logic. there are schematics of them on the gameboy developers web ring. Regards, Simon -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu