| 摘要 |
PURPOSE:To attain smooth service such as an interruption function to a busy extension or an extension camp-on function by informing with whom a called party is in talking at present when an extension desired to be called is busy. CONSTITUTION:When a subscriber STA-A dials the extension number of a called extension subscriber STA-B for the call, if the subscriber STA-B is in talking with other extension STA-C, the subscriber STA-A listens to a busy tone. When the subscriber STA-A dials a specific number decided in a station data, a central controller 2 reads a number dialed by the subscriber STA-A from a reception dial storage memory WDST-1 corresponding to an outgoing register trunk 4 connected to the subscriber STA-A so as to analyze that the subscriber STA-A is going to call the subscriber STA-B. Further, a connection destination storage memory (MIOT) is retrieved to detect the extension number of the subscriber STA-C to which the opposite party talks by the subscriber STA-B. As a result, the extension number of the subscriber STA-C thus obtained is displayed on a number display device 7. |
