
PCI Express 4-Port Industrial Serial I/O Card User Guide
6
Pin-out of one DB-37 female connector for four RS-422/485 ports
Pin
RS-422 Mode
RS-48
5 “4W” Mode
RS-
485 “2W” Mode
1
.NC.
.
2
TxD-(3)
TxD-(3)
Data-(3)
3
Ground
Ground
Ground
4
CTS+(3)
5
TxD+(3)
TxD+(3)
Data+(3)
6
CTS-(4)
7
RxD-(4)
RxD-(4)
8
RTS-(4)
9
RTS+(4)
10
RxD+(4)
RxD+(4)
11
TxD-(2)
TxD-(2)
Data-(2)
12
Ground
Ground
Ground
13
CTS+(2)
14
TxD+(2)
TxD+(2)
Data+(2)
15
CTS-(1)