Db9 Connectors - Comtrol DeviceMaster EIP Series Hardware Installation And Configuration Manual

Connecting Serial Devices

DB9 Connectors

This subsection provides the following information:
• Connector pin assignments (below)
• DB9 Null-Modem Cables (RS-232)
• DB9 Null-Modem Cables (RS-422)
• DB9 Straight-Through Cables (RS-232/485)
• DB9 Loopback Plugs
• Connecting DB9 Serial Devices
Pin
1 DCD
2 RxD
3 TxD
4 DTR
5 Signal GND
6 DSR
7 RTS
8 CTS
9 RI
† The following models support RS-485 full-duplex:
• 1-Port DIN rail models
• 2-Port DIN rail models
• 4-Port DIN rail models
Refer to the hardware manufacturer's installation documentation if you need help with connector pin outs or
cabling for the serial device. This illustrates the DB9 connector signals.
RS-232
GND
DTR
TxD
RxD
CD
Pin 1
DB9 Male
36 - Connecting Serial Devices
on Page 37
on Page 37
on Page 38
on Page 38
DB9 Connector Pin Outs
RS-422 and RS-485 Full-Duplex
RS-232
Not used
RxD-
TxD-
Not used
Signal GND
Not used
TxD+
RxD+
Not used
GND
RI
Not used
CTS
TxD-
RTS
RxD-
DSR
Not used
Pin 6
Pin 1
DB9 Male
DeviceMaster EIP | UP Hardware Installation and Configuration Guide: 2000633 Rev. C
on Page 37
(Master/Slave)†
RS-422
GND
Not used
Not used
RxD+
TRxD-
TxD+
Not used
Not used
Not used
Pin 6
Pin 1
RS-485
Half-Duplex
Not used
Not used
TRxD-
Not used
Signal GND
Not used
TRxD+
Not used
Not Used
RS-485
Not used
Not used
TRxD+
Not used
Pin 6
DB9 Male