The MC74F620 is an octal bus transceiver featuring inverting 3-state buscompatible outputs in both send and receive directions. The BN outputs are capable of sinking 64 mA and sourcing up to 15 mA, providing very good capacitive drive characteristics. The MC74F623 is a non-inverting version of the MC74F620. These octal bus transceivers are designed for asynchronous two-way communication between data busses. The control function implementation allows for maximum flexibility in timing. These devices allow data transmission from the A bus to the B bus or from B bus to A bus, depending upon the logic levels at the Enable inputs (OEBA and OEAB). The Enable inputs can be used to disable the device so that the busses are effectively isolated. The dual-enable configuration gives the MC74F620 and MC74F623 the capability to store data by the simultaneous enabling of OEBA and OEAB. Each output reinforces its input in this transceiver configuration. Thus, when both control inputs are enabled and all other data sources to the two sets of the bus lines are at high impedance, both sets of bus lines (16 in all) will remain at their last states.