| 摘要 |
Data signals are switched to a number of transmitting and receiving terminals, with at least one changeover unit being used to divide the signals into at least four different data channels and synchronising signals. One pair of the signal channels is in one direction, and another pair (T,C) is in the other direction. All channels in both directions are distributed over a common data bus simultaneously, and each of the terminals and all the channels both of the transmitting and receiving type, at the same time are received or transmitted via the bus and further outwards to the data network. Time signals are simultaneously distributed with other channels over a separate synchronising channel. Where one of the terminals makes a call to the data network, and the other terminals are passive, all signal channels in the calling terminal are connected to the connecting unit, the through coupling being maintained so that the calling terminal can exchange data with the network, with the non-calling terminals maintaining their transmission and reception circuits and their control and indicator circuits coupled together. |
