Communication control system

摘要

A communication control system arranged between a plurality of terminal apparatuses and a host processing unit in order to transmit and receive signals based on an NRZI coding system between them by way of a half duplex communication system, a "0" bit detecting circuit for detecting the "0" bit of a one-bit length is provided in the communication control system and the sending and receiving modes are automatically switched in accordance with the output of this detecting circuit.