Telephone network including common equipment with message information and control information circuits for connecting to stations having multifunction telephones

摘要

A private telephone network that includes multifunction telephones. Multifunction telephones are connected to common equipment by a voice signal path and a data signal path. Supervisory information passes over the data signal path in the form of polled messages that are sent from the common equipment to the telephone. Sense information is received by the common equipment from the telephone. The transmission is by frequency modulation, such as frequency-shift-keying modulation, techniques. At the multifunction telephone, a programmed microcomputer contains three blocks of instructions for enabling the microcomputer to perform background operations, to respond to the initial receipt of a message, and to thereafter transmit and decode the message. Further, in response to the decoding block of instructions, that are provided on a fixed time basis, the microcomputer is able to transmit frequency-shift-keyed signals without the need for a separate frequency-shift-keyed transmitter.