To find out an act of fraudulently initializing a random number generated in a game machine.

When a memory clear switch is pushed, a main board transmits a command for reporting that a random number generation is initialized to a sub board, and the sub board transmits a signal indicating that the random number generation is initialized to a hall computer. At the same time, the main board turns on two or more signals previously selected out of output signals of a concentrated terminal board and transmits them to the hall computer. When the hall computer receives the signal indicating that the random number generation is initialized from the sub board, in the case the two or more signals previously selected from the concentrated terminal board are not turned on at the same time, it is determined to be a fraudulent act. The signal indicating that the random number generator is initialized is transmitted to the hall computer with two systems through a sub control part and the concentrated terminal board, so that the fraudulent act can be detected reliably.