Abstract: A full duplex interface apparatus for a high performance serial bus is provided. More particularly, an IEEE 1394 interface apparatus is provided which includes a port switch having two ports coupled to a source generator device and a display device and separately receiving and buffering received signal packet data streams from the physical layer and transmit signal packet data streams for transmission over the physical layer. Accordingly, by coupling the source generator unit which generates signals for transmission over the physical layer through a first port of the port switch and the display unit to a second port of the port switch, ISO signals such as video signals may be received from the physical layer and provided to the display unit at the same time as ISO signals are being transmitted from the source generator unit to the physical layer through the port switch.