A game machine is provided with a controller control circuit including a data transfer control circuit. When the data in a first external RAM attached to a first controller is transferred to a second external RAM attached to a second controller, the data transfer control circuit transmits a predetermined command to the first controller. The data stored in the first external RAM is memorize through a data transfer control circuit. The data transfer control circuit then transmits a predetermined command to the second controller. In response thereto, the data stored in the internal RAM is transmitted to the second controller to be stored in the second external RAM.