SMC Networks SMC1255TX - Manual (Page 52)

C
ABLE
S
PECIFICATIONS
42
The figure below illustrates how the pins on the RJ-45 connector
are numbered. Be sure to hold the connectors in the same
orientation when attaching the wires to the pins.
With 10BASE-T/100BASE-TX cable, pins 1 and 2 are used for
transmitting data, and pins 3 and 6 for receiving data. The “+”
and “-” signs in the tables below are used to represent the
polarity of the wires that make up each wire pair.
RJ-45 Pin Assignments
Pin Assignment
1 Tx+
2 Tx-
3 Rx+
6 Rx-