Cisco Systems 2940 manual Identifying a Rollover Cable

Appendix B Connectors and Cables

Cable and Adapter Specifications

Table B-3 Console Port Signaling and Cabling Using a DB-25 Adapter

Console	RJ-45-to-DB-9		RJ-45-to-DB-25	Console
Port (DTE)	Adapter Cable		Terminal Adapter	Device
Signal	RJ-45 Pin	DB-9 Pin	DB-25 Pin	Signal
RTS	1	8	5	CTS
Not	2	6	6	DSR
connected
TxD	3	2	3	RxD
GND	4	5	7	GND
GND	5	5	7	GND
RxD	6	3	2	TxD
Not	7	4	20	DTR
connected
CTS	8	7	4	RTS

Identifying a Rollover Cable

You can identify a rollover cable, also known as a “crossover” cable, by comparing the two modular cable ends. Hold the cable ends side-by-side, with the tab at the back, right plug, as shown in Figure B-12.

Figure B-12 Identifying a Rollover Cable

1 2

89889

1

2

Pin 1

Pin 9

On a rollover cable, the wire connected to the pin on the outside of the left plug should be the same color as the wire connected to the pin on the outside of the right plug.

Catalyst 2940 Switch Hardware Installation Guide

OL-6157-01 B-9