Atari 400 or 800/800XL DYI mini-size cartridge PCB You will need:- One 74LS00 in DIP package- Two 10K resistors- One 100n capacitor- Two DIP switches (select one of for 16K ROM blocks). You can use solder jumpers instead if you want. - One 28-pin DIP socket - 27C256 or 27C512 ROM chipPCB from quality manufacturer. I shjp same day