Cabletron Systems SmartSTACK 100 - Manual (Page 95)

Technical Specifications
A-5
a. The “+” and “-” signs are used to represent the polarity of the two
wires that make up each wire pair.
A.4 STRAIGHT-THROUGH WIRING
If the twisted-pair link segment is to join two ports on a switch,
and only one of the ports has an internal crossover, the two pairs of
wires must be straight-through, as shown in Table A-4.
A.5 CROSSOVER WIRING
Two ELS100-16TXs can communicate only if the transmitter on one
unit is connected to the receiver on the other unit. This reversal, or
crossover function, can be implemented either in the wiring or in
the device itself. When connecting ELS100-16TXs, a crossover must
be implemented in the wiring. Refer to Table A-5 for crossover pin
assignments.
Table A-3. 100BASE-T Pin Assignments
Pin Assignment a
1 Rx+
2 Rx-
3 Tx+
6 Tx-
Table A-4. Straight-Through RJ45 Pin Assignments
ELS100-16TX (Crossed) Device (Not Crossed)
1 (Rx+) 1 (Tx+)
2 (Rx-) 2 (Tx-)
3 (Tx+) 3 (Rx+)
6 (Tx-) 6 (Rx-)