User Guide

9
Building DB25 Male Loopback Plugs
Building DB25 Male
Loopback Plugs
Loopback plugs are used with the diagnostics to test
serial ports.
This loopback plug is used with the standard 8- and
16-port DB25 interface boxes.
•Pins 2 to 3
• Pins 4 to 5 to 22
• Pins 6 to 8 to 20
Wire the following pins together for an RS-422
loopback plug.
• Pins 15 to 19
• Pins 17 to 25
RJ45 Interfaces The RocketPort PCI/4J, an Octacable model, and the Rack Mount interface boxes
are available with RJ45 connectors.
RJ45 Pinouts Use the following table and figures for pinout
information on the
RJ connectors used on the
Octacable, and Rack Mount interface boxes.
Pin 13 Pin 1
Pin 14Pin 25
RS-232 Only (Back View)
Pin 25 Pin 14
Pin 1Pin 13
RS-422 Only (Back View)
Pin RJ45
1RTS
2DTR
3GND
4TxD
5RxD
6DCD
7DSR
8CTS
RJ45 Interface Box
Pin RS-232 RS-422
1 RTS TxD+
2DTR Not used
3GND
Tied to ground on the card,
but it is not used in the cable
4 TxD TxD-
5RxD RxD-
6DCD Not used
7DSR Not used
8CTS RxD+
Note: Ring indicator is not supported on the
RJ45 connector.
Pin 1
Pin 8
RJ45
Receptacle
Pin 1