PURPOSE: To realize the automatic recovery for the order execution of the microprocessor by providing the time-over detector as well as the time counter which counts the duration time for the order stop state, the order execution queuing state and the order execution holding state each and thus detecting the hang-up state.

CONSTITUTION: Time counter 6 counts the duration time for the order stop state, the order execution queuing time and the order execution holding state each of microprocessor 1. And at the same time, time-over detector 7 detects the time-over. After detection of the time-over, detector 7 applies the system reset interruption to processor 1 and also gives system freezing 19 to other control mechanisms. And processor 1 performs the identification for the fault position at the system reset operation time and other necessary treatments. Thus the hang-up state is detected, and the automatic recovery is ensured for the order execution of processor 1.