Interrupt circuit and interrupt processing method for microcomputer

Abstract

An interrupt circuit for a microcomputer, in which requests for multiple interrupt processing arise at the same time, are executed in the assigned priority order. To assign a processing priority, the interrupt circuit comprises a first priority assignment control circuit and a second priority assignment control circuit. Furthermore, in order to execute a high priority interrupt processing with a minimum lag time, the present invention comprises the steps of: issuing a software interrupt request signal assigned a lower priority while executing an interrupt request based on a request signal assigned a high priority level; executing a minimum required processing based on the request signal with a high priority level; executing and completing processing based on a request signal assign a low priority level; and resuming, by the software interrupt request signal, a rest part of the interrupted processing based on the request signal with a high priority level, whereby the plurality of interrupt requests which occurred at the same time can be processed with high efficiency