| 摘要 |
A mobile communication device 10 has a battery 3 and control means 7 which enable the device to selectively receive power from the battery 3 or from a data terminal 30 via a modem 20. A further aspect relates to a modem or power supply device for supplying power to the communication device. When a control section 8 of the mobile communication device 10 detects a voltage drop of the battery 3 during wireless data communication through packet transmission, the control section 8 temporarily stops transmission in the state where reception is maintained. The mobile communication device receives power from the data terminal 30 connected to the mobile communication device 10 through a modem card 20. When an exchange of batteries is ended and a battery voltage is 10 recovered, transmission is resumed. Transmission data during a period when the transmission is stopped, is stored in a RAM in the modem card 20. |
