| 摘要 |
The data communication unit transfers (TLU) incoming signals from the transmission medium (TN) e.g. telephone line to a form suitable for transmission to the data processor (DTE) and signals originating in the processor to a form suitable for transmission via the medium. Communication between the processor and the transfer device controller (CCU) is effected via the data link. This controller (CCU) has two transmission channels, one for data from the processor and one for data from the transmission medium. Each channel has a separation arrangement (5,11) for dividing incoming data into one part for feed straight through the communication control, and another part for retention by the communication control as being addressed to it. In each channel is a buffer register arrangement (6,7,12,13) for intermediate storage of incoming data, and a data flow regulator (8,14). The separation arrangement comprises an address decoder (5,11) which scrutinises the incoming data flow for the presence of one or more code words, i.e. addresses, which signify mode changeover from or to through feed mode to or from control mode. |
