Rj11 loopback plugs – Comtrol RocketPort EXPRESS User Manual
Page 20
20 - Connecting Serial Devices
RocketPort EXPRESS User Guide: 2000481
Rev. E
RJ11 Straight-Through Cable (RS-232 or RS-485 Half-Duplex)
RJ11 Straight-
Through Cable (RS-
232 or RS-485 Half-
Duplex)
Use straight-through cables to connect modems and other DTE devices. For
example, you can connect one end of a straight-through cable to COM2 on one
computer and the other end of the straight-through cable to a modem.
RJ11 Loopback
Plugs
RocketPort EXPRESS models with RJ11 connectors are shipped with
a a single loopback plug (RS-232/422).
Wire the following pins together to build additional loopback plugs or
replace a missing RS-232/422 loopback plug:
•
Pins 3 to 4
•
Pins 1 to 6
DTR
TRxD+
1
DCD
RxD
TxD TRxD-
DTR TRxD+
GND
Signal
DCD
RxD
TxD
TRxD-
GND
Signal
RJ11
5
4
3
2
Pins
DB25
8
3
2
20
7
Pins
RocketPort
DCE Serial Device
DB9
1
2
3
4
5
Pins
CTS
CTS
6
5
8
RS-232 RS-485HD
RS-232 RS-485HD