POWER SAVING CONTROL SYSTEM

摘要

PURPOSE:To perform state transition control over respective CPUs and individual power saving control corresponding to the operation state so that the power consumption of a system in a stand-by state is suppressed without spoiling the consistency of the whole operation. CONSTITUTION:A multiprocessor system equipped with plural CPUs is provided with a processor bus monitor part 156 which detects the operation states of the individual CPUs by monitoring a processor bus and a system state monitor part 101 which monitors the load state of the system. Further, the system is provided with a system state control part 102 which controls the power consumption of the individual CPUs according to a report from the system state monitor part 101. If a state wherein the load on a specific CPU is small because of a key input waiting state continues, that is informed by the processor bus monitor part 156 to the system state control part 102, which sends a command to a clock switching part 153 to switch the clock supplied to the CPU to a low frequency.