| 摘要 |
A method for indicating the charge status of a backup power supply of a communication device includes detecting the charge status of the backup power supply. If the charge status of the backup power supply is lower than or equal to a predetermined charge status, the communication device alerts via a telephone connected thereto. The communication device alerts a user by sounding one or more tones if the telephone is off-hook, and alerts user by sounding one or more rings if the telephone is on-hook. |
