DS14C89A/DS14C89AT (RS-232 SERIAL PORT DEVICES) Quad CMOS Receiver +-----------+ INPUT A |1 +--+ 14| VCC NC |2 13| INPUT D OUTPUT A |3 12| NC INPUT B |4 DS14 11| OUTPUT D NC |5 C89 10| INPUT C OUTPUT B |6 9| NC GND |7 8| OUTPUT C +-----------+