| 摘要 |
PROBLEM TO BE SOLVED: To detect an in correct branch even when the incorrect branch is generated at the storage address of instruction word by generating the disturbance of program counter when executing a microcomputer program. SOLUTION: A counter 2 is provided for counting the execution time of the instruction word and operand word of program by a clock CK every execution, integrating the count vague for each of execution and outputting a count value C. A parity generating part 5 is provided with party generating part 41 and 42 for respectively discriminating the parity of the count value C and that of read data D while receiving the supply of the count value C and read data D and an exclusive OR(EXOR) circuit 43 for outputting a discriminating signal O/E by EXORing these discriminated results. |
