UMAC-CPCI Turbo CPU Board Hardware Reference Manual
Connector Pinouts 19
J4: RS-232 Serial Port Connector
(DB-9S Connector)
Pin # Symbol Function Description Notes
1 N.C. No connect
2 TXD- Output Send Data Low TRUE
3 RXD- Input Receive Data Low TRUE
4 DSR Bidirect Data Set Ready Shorted to DTR
5 GND Common UMAC CPCI Reference
6 DTR Bidirect Data Terminal Ready Shorted to DSR
7 CTS Input Clear to Send High TRUE
8 RTS Output Request to Send High TRUE
9 N.C. No connect
Jumpers E17 and E18 should connect pins 1 and 2 to use th is port for RS-232 communications; they should connect pins 2
and 3 to use this port for RS-422 communications.