Abstract: A tri-port transceiver for receiving, switching and transmitting digital information among its ports. An input to each port is coupled to a multiplexer of each other port, wherein the multiplexer of each other port, wherein the multiplexers provide the switching of signals onto other ports. A buffer and a latch are used to couple each input port signal to the multiplexers, and a driver coupled to the multiplexer provides transmission of the selected signal from the multiplexer. An EPROM based PLA operates as a programmable state machine to generate control signals to the tri-port transceiver. In one embodiment, a programmable output impedance driver is used.