| 摘要 |
PROBLEM TO BE SOLVED: To provide a key telephone system which has a route-switching function at the time of modem communication and whose communication rate at the time of modem communication can be improved. SOLUTION: When a modem 4 connected to an analog terminal connecting adapter 3 fitted to a key telephone set 2 closes a line for calling, the control part 10 of a main device 1 recognizes the usage state of a trunk line 5-N connected to a change-over switch 17 in the analog terminal connecting adapter 3 and determines whether the control part 10 of the main device 1 can be used, when it is not being used. The key telephone set 2 changes over the change-over switch 17 to a trunk line-side and modem communication is realized without the aid of a codec.
|
