Rj45 Null-Modem Cables (Rs-422); Straight-Through Cables (Rs-232/485); Rj45 Loopback Plugs; Rs-485 Test Cable - Comtrol DeviceMaster Up Hardware Installation Manual

RJ45 Null-Modem Cables (RS-422)

RJ45 Null-Modem
Cables (RS-422)
Straight-Through
Cables (RS-232/485)
RJ45 Loopback
Plugs

RS-485 Test Cable

30 - DeviceMaster UP User Guide: 2000451 Rev. C
Use the following figure if you need to build an RS-422 null-modem RJ45 cable. A
null-modem cable is required for connecting DTE devices.
Note: RS-422 pinouts are not standardized. Each peripheral manufacturer uses
different pinouts. Please refer to the documentation for the peripheral to
determine the pinouts for the signals above.
Use the following figure if you need to build an RS-232 or RS-485 straight-through
cable. Straight-through cables are used to connect modems and other DCE
devices. For example, a straight-through cable can be used to connect COM2 of one
PC to COM2 to a modem.
Signal
DCD
RxD
TxD or TRx-
DTR
GND
DSR
RTS or TRx+
CTS
RI
Loopback connectors are RJ45 serial port plugs, with pins wired together as
shown, that are used in conjunction with application software (Test Terminal or
Minicom) to test serial ports. The DeviceMaster UP is shipped with a a single
loopback plug (RS-232/422).
• Pins 4 to 5
• Pins 1 to 8
• Pins 2 to 6 to 7
You can use a straight-through cable as illustrated previously, or build your own
cable.
Note: RS-422 pinouts are not standardized. Each peripheral manufacturer uses
different pinouts. Please refer to the documentation for the peripheral to
determine the pinouts for the signals above.
RJ45 RJ45
Signal
Pins Pins
TxD+ 1
TxD- 4
RxD+
8
RxD- 5
DB9 RJ45
RJ45
Pins Pins
Pins
6
6 1
5 2 5
4 3 4
4 2
2
5 3
3
6 7
7
1 7 1
8 8
8
N/A
N/A 9
1 8
Plug
Top View
Cable
RJ45
Pins Signal
Signal
4
TRX-
1
TRX+
Signal
RxD+
RxD-
TxD+
TxD-
DB25
Pins Signal
8
DCD
3
RxD
2
TxD or TRx-
20
DTR
7
GND
6
DSR
4
RTS or TRx+
5
CTS
22 RI
The RS-232 loopback plug also
works for RS-422.
TRX-
TRX+
Connecting Serial Devices