MC74AC643 Overview
MC74AC643 MC74ACT643 Octal Bidirectional Transceiver with 3ĆState Outputs The MC74AC643/74ACT643 octal bus transceiver is designed for asynchronous two-way munication between data buses. The device transmits data from bus A to bus B when T/R = HIGH, or from bus B to bus A when T/R = LOW. The enable input can be used to disable the device so the buses are effectively isolated.