Patent attributes
An appropriate recovery process is made possible according to the situation of a power supply anomaly. When a system reset occurs, a storage unit stores an operation state of a system immediately before the reset in an operation state memory and also stores a recovery mode determined according to the stored operation state in a recovery mode memory. At the beginning of the recovery process, a necessary process is performed according to the stored recovery mode. Each time the recovery process is performed, a recovery counter performs enumeration and a normal-operation-time timer counter enumerates a normal operation time of the system. Such processes as a system halt and an engine recovery are performed according to the enumerated value and the normal operation time enumerated by the counters.