| 摘要 |
PROBLEM TO BE SOLVED: To solve a cost problem of a real time clock to correct time by receiving a reference time by a radio wave or the like. SOLUTION: An image forming device 100 obtains the estimated error of a RTC 127 from a PDA 120, and if the estimated error of a RTC 104 is bigger, it obtains the present time of the RTC 127 from the PDA 120 to correct the time of the RTC 104. In addition, the corrected time is memorized in a RAM 102, and the estimated error of the RTC 127 is memorized in the RAM 102 as the present estimated error of the RTC 104. The estimated error of the RTC 104 is found from an elapsed time from when the RTC 104 was corrected last time, the accuracy of RTC, and the estimated error at the time when the RTC 104 was corrected last time. |
