| 摘要 |
PURPOSE:To make terminal connection work unnecessary at the time of connecting a PCM link by detecting that the PCM link is not connected in terms of a remote line concentrator, by setting automatically an internal highway to be connected to the PCM link in the folding state and by utilizing said internal high-way as a channel for call in the remote line concentrator. CONSTITUTION:A selection circuit 45, provided on each downward internal highway 44(1) of a channel device 42, is equipped with a terminal 48 arriving at a digital terminal station 43'. When a PCM link 3 is connected to a remote line concentrator and a digital terminal station device 43' is loaded, the PCM link 3 is aotumatically connected to the internal highway 44 of the channel device 42 through the digital terminal station 43'. Conversely, when the PCM link 3 is not connected to the remote line concentrator 4 and the digital terminal station device 43' is not loaded, the corresponding internal highway 44 is set in the folded state and used as a channel for its own call. Accordingly the connection at every one terminal becomes unnecessary. |
