and, Igot the read / write check backwards, here's the corrected code... 300:AD 12 C0 30 04 A9 BF D0 14 AD 00 E0 EE 00 E0 CD 00 E0 F0 07 CE 00 E0 A9 D7 D0 02 A9 D2 20 ED FD A9 B1 AE 11 C0 30 02 A9 B2 20 ED FD A9 8D 4C ED F0 instead of D0 BEQ instead of BNE