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 this port for RS-232 communications; they should connect pins 2
and 3 to use this port for RS-422 communications.