Multiple CPU system including automatic power supply restoration following instantaneous shutdown

Abstract

A multiple-CPU system including a main CPU and at least one subordinate CPU connected thereto. Both the main and subordinate CPU are provided with a respective voltage detector circuit for detecting when a main or primary power supply voltage for the CPU's has dropped below a predetermined threshold level. When the respective detector circuit outputs a signal indicating detection of the drop in main power supply voltage, the respective CPU is placed in a standby state. However, the threshold level of the detector circuit of the main CPU is set to a voltage lower than the threshold level of the detector circuit of the subordinate CPU. As a result, the subordinate CPU is placed in a standby state before the main CPU. The main CPU is equipped with an auxiliary power supply so that when the subordinate CPU is placed in a standby state, automatic recovery is thereafter carried out by the main CPU.

Dependencies are inferred from the claim text.