Cisco WS-C3750X-24T-L Hardware Installation Guide - Page 127

60915 Appendix B Connector and Cable Specifications Connector Specifications Figure B-1 10/100/1000 Port Pinouts Pin Label 1 TP0+ 2 TP0- 3 TP1+ 4 TP2+ 5 TP2- 6 TP1- 7 TP3+ 8 TP3- 12345678 10/100 Ports The 10/100 Ethernet ports use standard RJ-45 connectors and Ethernet pinouts with internal crossovers, as shown by an X in the port name. These ports have the transmit (TD) and receive (RD) signals internally crossed so that a twisted-pair straight-through cable and adapter can be attached to the port. Figure B-2 shows the pinout. Note On switches running Cisco IOS Release 12.1(14)EA1 or later, you can use the mdix auto command in the CLI to enable the automatic crossover feature. When the automatic crossover feature is enabled, the switch detects the required cable type for copper Ethernet connections and configures the interfaces accordingly. Therefore, you can use either a crossover or a straight-through cable for connections to a copper 10/100 or 10/100/1000 port on the switch, regardless the type of device on the other end of the connection. The automatic crossover feature is disabled by default. For configuration information for this feature, refer to the switch software configuration guide or the switch command reference. 78-15136-02 Catalyst 3750 Switch Hardware Installation Guide B-3