DIGITAL SWITCHING SYSTEM CONNECTING BUSES WITH INCOMPATIBLE PROTOCOLS AND TELEPHONE ANSWERING SYSTEM AND PRIVATE AUTOMATIC BRANCH EXCHANGE WITH INTEGRATED VOICE AND TEXTUAL MESSAGE RECORDING

A digital switching system connecting buses with incompatible protocols and a telephone answering system and private automatic branch exchange with integrated voice and textual message recording is disclosed. The digital switching system (10) in accordance with the invention permits a digital switching matrix (12) having an input bus and an output bus to connect information on the input bus selectively to information on the output bus in response to control signals applied to switches of the switching matrix. A plurality of information systems (18, 20 and 22) each having a different bus protocol are electrically connected to the input and output buses of the switching matrix to permit information transmitted on a conductor of any of the information buses to be received by another conductor of any of the information buses through the input bus, the switching matrix and the output bus. A host processor controls the plurality of information systems. Furthermore, the host processor may be used to commonly control textual message and voice message recording systems within a telephone answering system and commonly control telephony functions and textual message and voice recording systems within a PABX.