Allen-Bradley MicroLogix 1200 User Manual page 71

Constructing Your Own Modem Cable
If you construct your own modem cable, the maximum cable length is
15.24 m (50 ft) with a 25-pin or 9-pin connector. Refer to the
following typical pinout for constructing a straight-through cable:
DTE Device
(AIC+,
MicroLogix,
SLC, PLC, etc.)
9-Pin
3 TXD
2 RXD
5 GND
1 DCD
4 DTR
6 DSR
8 CTS
7 RTS
Constructing Your Own Null Modem Cable
If you construct your own null modem cable, the maximum cable
length is 15.24 m (50 ft) with a 25-pin or 9-pin connector. Refer to the
following typical pinout:
DTE Device
(AIC+,
MicroLogix,
SLC, PLC, etc.)
9-Pin
3 TXD
2 RXD
5 GND
1 DCD
4 DTR
6 DSR
8 CTS
7 RTS
Communication Connections
DCE Device
(Modem,
PanelView,
etc.)
25-Pin 9-Pin
TXD 2 3
RXD 3 2
GND 7 5
DCD 8 1
DTR 20 4
DSR 6 6
CTS 5 8
RTS 4 7
DCE Device
(Modem,
PanelView, etc.)
25-Pin 9-Pin
TXD 2 3
RXD 3 2
GND 7 5
DCD 8 1
DTR 20 4
DSR 6 6
CTS 5 8
RTS 4 7
Publication 1762-UM001D-EN-P - March 2004
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