| 摘要 |
A key telephone system including a key service unit, a plurality of key telephone station sets which are connected via speech lines for transmission of speech signals and via data lines for transmission of data, and a device provided at the key service unit for sending a predetermined discrimination signal to a selected key telephone station set via an associated speech line, whereby the key service unit sends key telephone station set information to the plurality of key telephone station set via the data lines, and each of the plurality of key telephone station sets derives its own key telephone station set information from the key telephone station set information sent via the data lines, on the basis of the discrimination signal sent via the speech line. |
