| 摘要 |
PROBLEM TO BE SOLVED: To suitably always output information regarding a time function by providing a means for counting time information and a means for holding initial set information to the counting means, and further providing a means for holding counting starting state information for power supplying only by a back-up power source. SOLUTION: A clock controller 30 has a clock 31 and a memory 32 for the clock. The clock 31 counts a present time, and the memory 32 for the clock sequentially holds a present time. The controller 30 is driven by a special purpose back-up power source. Initial set information indicating whether the clock 31 is initialized or not is written in a nonvolatile memory 65 included in a control unit 50. According to this constitution, whether an error is generated in the clock 31 or not is detected based on information held by the memory 65 and the memory 32, and a type of the generated error can be specified. Accordingly, at the time of the error of the clock, annotation information at each error cause can be output. |
