General Description
The ACT899 is a 9-bit to 9-bit parity transceiver with transparent latches. The device can operate as a feed-through transceiver or it can generate/check parity from the 8-bit data busses in either direction. The ACT899 features independent latch enables for the A-to-B direction and the B-toA direction, a select pin for ODD/EVEN parity, and separate error signal output pins for checking parity.

Features
■ Latchable transceiver with output sink of 24 mA
■ Option to select generate parity and check or “feed-through” data/parity in directions A-to-B or B-to-A
■ Independent latch enable for A-to-B and B-to-A directions
■ Select pin for ODD/EVEN parity
■ ERRA and ERRB output pins for parity checking
■ Ability to simultaneously generate and check parity
■ May be used in system applications in place of the 280
■ May be used in system applications in place of the 657 and 373 (no need to change T/R to check parity)