Rockwell Automation Allen-Bradley ControlLogix 1756-MVI Installation Instructions Manual page 13

Refer to the following tables to identify the signals on each of the
1756-MVI module's ports.
IMPORTANT
DB-9M Pin
1
2
3
4
5
6
7
8
9
Metal Shell
IMPORTANT
PRT1 Signals
DB-9M Pin
1
2
3
4
5
6
7
8
9
Metal Shell
The cable length for PRT1 must not exceed ten (10)
feet.
PRT2, PRT3 Signals
Jumper Set to
RS-232 Signal
DCD
RxD
TxD
DTR
COM/GND
DSR
RTS
CTS
--
Shield
The cable length for PRT2 and PRT3 must not
exceed:
50 feet for RS-232 signals
•
4000 feet for RS-422 and RS-485 signals
•
ControlLogix Multi-Vendor Interface Module
RS-232 Signal
DCD
RxD
TxD
DTR
COM/GND
DSR
RTS
CTS
--
Shield
Jumper Set to
RS-422 Signal
TxD+
RxD+
--
--
COM/GND
RxD–
--
TxD–
--
Shield
Publication 1756-IN001A-US-P - May 2000
Jumper Set to
RS-485 Signal
TxD/RxD+
--
--
--
COM/GND
--
--
TxD/RxD–
--
Shield
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