| 摘要 |
PROBLEM TO BE SOLVED: To provide a function of allowing a watchdog circuit to be arbitrarily stopped and restarted, to prevent the function from unexpectedly stopping, and to allow the watchdog circuit to be easily and immediately restored to an operable state if the watchdog circuit is stopped unexpectedly.SOLUTION: A prescribed data signal inputted from the outside is taken in synchronously with a timer refresh instruction, and a timer control circuit stops a counting operation of a count clock signal in a timer circuit when reference data as the data signal of a plurality of latest bits taken in sequentially matches a prescribed pattern and satisfies another prescribed condition. When the reference data does not match the prescribed pattern or does not satisfy the another prescribed condition while the counting operation is stopped, the timer control circuit restarts the counting operation of the count clock in the timer circuit. |
