dtvwiki

Basically for games to be played with a joystick on the Hummer they need to be patched to read from the userport rather than the joystick port. The userport address is hex memory location $DD01. Joystick port 1 & 2 are memory locations $DC01 & $DC00. In this case it’s important to note the reverse in order versus port number so $DC00=port2 and $DC01=port1.