| 摘要 |
PURPOSE:To recognize the remaining service life of a battery by measuring a time or the equivalent when power is supplied to a reception section receiving a radio signal, calculating the service life of the battery based on a measured value and displaying the result. CONSTITUTION:When an MPU 1 detects that a power switch SW1 is closed, a decoder section 4 sends a signal (a), a counter 7 counts a signal from an oscillation frequency divider circuit 6 and the count is being increased. The count is fed to the MPU 1. Moreover, the MPU 1 reads a value corresponding to the longest available time of the battery 13 from a ROM 17, decrements the count of the counter 7 to obtain a value corresponding to the remaining service life time of the battery 13. When a switch SW5 is operated in the said normal mode, the MPU 1 reads the remaining service life time of the battery 13 from the remaining service life time storage register in a RAM 16, and displays the time onto an LCD 21. |
