| 摘要 |
PURPOSE:To efficiently transmit the data from a vehicle communication device to a base station by switching automatically a transmitting mode to a voice mode after the transmission of vehicle position data is completed by a data communication mode. CONSTITUTION:The command to send an off-hooking signal from a CPU22 to a line network control device 40 and the dial number at a base side set beforehand is sent, and a line with the base side is opened. It is confirmed that the line is opened, a signal is sent to a mode switching device 50 and the line is switched into the mode of MODEM. Thereafter, the information determined beforehand such as a vehicle number and plural vehicle positions including the newest position data stored in a RAM 35 is sent to a base station side. At such a time, a termination signal to show that necessary data to be transmitted are completed is incorporated to the last of the data. When a data receiving termination signal is received from the base station and the operation of a timer 30 is started, simultaneously, a signal is sent to the device 50, a line is switched to a hand-free machine and a voice call is started. |
