| 摘要 |
<p>PURPOSE:To improve an operability by continuously attaining a communicating operation in an operating state before a battery exchange even when the battery exchange is operated during a communication. CONSTITUTION:This device is equipped with a non-volatile memory 21 which always stores information indicating the latest operating state of a portable radio telephone set, and timer circuit 37 which clocks a power source supplying and interrupting time. Then, at the time of the start of a power supply by the mounting of a battery 40, a control circuit 20 reads the information of the terminal voltage value of the timer circuit 37, compares it with a threshold value Vb, judges the battery exchange during the communication when the terminal voltage value of the timer circuit 37 is more than the threshold value Vb, and restores the operating state of the portable radio telephone set to the operating state just before the power supply is interrupted due to the battery exchange based on the information stored in the non-volatile memory 21.</p> |
