摘要 |
To detect an abnormality in an interrupt control system without completely depending on dualization of a circuit, without the need to create a test pattern for a built-in self-test by spending time, and without considerably increasing an amount of power consumption. A test interrupt request is generated periodically using a timer or the like in an interrupt signal system from an interrupt controller to a central processing unit, the state of an interrupt request flag within the interrupt controller is checked in an interrupt processing routine, and in the case where it is detected that the same interrupt request flag is kept in a set state twice or more in succession, it is supposed that there is a high possibility that a failure has occurred in the interrupt signal system and it is considered that there is an abnormality. |