DATA COMMUNICATION SYSTEM

A data communication system includes a communicating medium and a plurality of transceivers connected to the medium, each including a transmitter for transmitting phase-encoded data onto the medium and a receiver for receiving phase-encoded data communicated on the medium by another transceiver. A digital phase decoder is coupled to the receiver of each transceiver for decoding the data received and applying at its output a decode signal representative of the character of the received data. The decode signal is at a predetermined value whenever data communicated on the medium by another transceiver is received by the subject receiver during the time the subject transmitter is transmitting data onto the medium. Circuitry is included for interrupting the transmission of data whenever the decode signal is detected to be at said predetermined value.