| 摘要 |
PURPOSE:To judge whether or not a battery is replaced by providing a battery replacement read register, setting a register at the time of the power source startup of a battery, and reading its contents by a CPU. CONSTITUTION:When the battery 5 is replaced, the power source startup of the battery is detected by a battery power source startup detecting means 3 and the battery replacement detection register 2 is set. When a CPU 4 is powered on, the contents of the register 2 of the timepiece 7 which is outputted through a bus 6 are read by the CPU 4 and unless H is set, it is judged that the battery is already replaced; and the frequency dividing counter 1 and register 2 of the timepiece 7 are reset and new time is set again. When the contents of the register 2 are L, on the other hand, the battery is not replaced, so the CPU 4 read the time data of the clock 7. Thus, the battery replacement state is found, so the processing on the side of the CPU 4 is performed efficiently. |
