CLOCK MONITORING CIRCUIT, INFORMATION PROCESSING APPARATUS AND CLOCK MONITORING METHOD

摘要

A check circuit (100) is provided in which in order to monitor clocks of an apparatus operating in synchronism with those clocks, units each performing a clock operation are divided into a plurality of functional or regional units, each of which includes a respective FF (10) performing a clock operation. The value of the FF (10) of the check circuit (100) is inverted at constant intervals and transmitted along a loop between one functional or regional unit and another. An error detecting circuit (20) checks whether the returned value of the FF (10) varies in a predetermined time period. If no change occurs in the predetermined time period, it is regarded as an error.