METHOD AND CIRCUIT FOR DETECTING FAULT OF MICROCOMPUTER

摘要

PURPOSE:To improve the fault detection rate of a microcomputer and to shorten time from the occurrence of a fault to detection with simple configuration. CONSTITUTION:A microinstruction 14 being the internal state of the computer is compared with prescribed instruction data in a comparison data memory 5 at a comparator 4. When they coincide, a counter 6 is reset by a reset signal 15. When the microinstruction 14 similar to prescribed instruction data does not appear and the reset signal does not come even if prescribed time elapses, the counter 6 overflows and outputs an error detection signal 16.