APPENDIX C Cables and Pinouts 10/100BASE-TX Pin Assignments
10/100BASE-TX PIN ASSIGNMENTS
Use unshielded twisted-pair (UTP) or shielded twisted-pair (STP) cable for RJ-45 connections: 100-ohm Category 3 or better cable for 10 Mbps connections. Also be sure that the length of any twisted-pair connection does not exceed 100 meters (328 feet).
The RJ-45 port on the access point supports automatic MDI/MDI-X operation, so you can use straight-through or crossover cables for all network connections to PCs, switches, or hubs. In straight-through cable, pins 1, 2, 3, and 6, at one end of the cable, are connected straight through to pins 1, 2, 3, and 6 at the other end of the cable.
Table 4: 10/100BASE-TX MDI and MDI-X Port Pinouts
PIN | MDI Signal Namea | MDI-X Signal Name |
| | |
1 | Transmit Data plus (TD+) | Receive Data plus (RD+) |
| | |
2 | Transmit Data minus (TD-) | Receive Data minus (RD-) |
| | |
3 | Receive Data plus (RD+) | Transmit Data plus (TD+) |
| | |
6 | Receive Data minus (RD-) | Transmit Data minus (TD-) |
| | |
4, 5, 7, 8 | Not used | Not used |
a.The “+” and “-” signs represent the polarity of the wires that make up each wire pair.
STRAIGHT-THROUGH WIRING
If the twisted-pair cable is to join two ports and only one of the ports has an internal crossover (MDI-X), the two pairs of wires must be straight- through. (When auto-negotiation is enabled for any RJ-45 port on this switch, you can use either straight-through or crossover cable to connect to any device type.)
You must connect all four wire pairs as shown in the following diagram to support Gigabit Ethernet connections.
