1 X N COMMUNICATION SYSTEM FOR PRIVATE BRANCH EXCHANGE

摘要

A press-talk trunk in a communication system receives press-talk signals from voice terminals having press-talk switches. In one aspect of the invention, the press-talk trunk is scanned by a central controller that selects an active press-talk signal and sets up a corresponding 1 x N voice communication path among the terminals. In another aspect of the invention, the press-talk trunk itself selects an active press-talk signal and notifies the central controller by means of an interrupt. In yet another aspect of the invention, the press-talk trunk also receives voice signals from all the terminals, selects a voice signal from a terminal having an active press-talk signal, and sends that voice signal back to all the other terminals. In still another aspect of the invention, two or more press-talk trunks are cascaded.