SMC Networks 1255TX User Manual page 25

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
1
2
3
6
Assignment*
Tx+
Tx-
Rx+
Rx-
C S
ABLE PECIFICATIONS
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