| 摘要 |
PURPOSE:To get a callback service through an optional line by reading a telephone set registering the callback service and a line connected to the said telephone set from a storage device in making the callback service and applying callback to a telephone set only registering the callback service. CONSTITUTION:A multi-line telephone set A1 registers the callback service by using a line alpha. In this case, a central processing unit CC 7 stores the information of the line alpha and the telephone set A1 connected to the line alpha to a main storage device MU 8. The multi-line telephone set A1 registers the callback service and restores itself. In making the callback service, the central processing unit CC 7 reads the information of the line alpha and the telephone set A1 connected to the line alpha stored in the main storage device MR 8 to connect the multi-line telephone set A1 and the line alpha for callback service. |
