| 摘要 |
<p>PURPOSE:To record a system state and the time at which a power source is disconnected, by recording the system state and the time at which the power source is disconnected to a management table in a nonvolatile memory which is backed up by a backup power source. CONSTITUTION:When access to a storage device 7 is required, the contents of an access status setting memory of the storage device 7 which is provided in an interface 8 are set, for instance, to '1' at the time of 'reading', and to '2' at the time of 'writing', and set to '0' for showing 'in the course of non-access' at the time point when those processing is ended. If a power source disconnection interrupting signal is inputted from a signal line 6, an MPU 1 shifts the processing to a power source disconnection interrupting routine, reads out an access status of the storage device 7 from the access status setting memory in the interface 8 in the course of said routine, and also, reads out time of that time from a timepiece 10, and records both these data as a pair in an access status area 11 and a time area 12 of the latest position of the management table in a CMOS RAM 4.</p> |
