User guide

Cables and Pinouts
C-2
C
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.
Figure C-2 Straight-Through Wiring
Crossover Wiring
If the twisted-pair cable is to join two ports and either both ports are labeled with an
“X” (MDI-X) or neither port is labeled with an “X” (MDI), a crossover must be
implemented in the wiring.
Figure C-3 Crossover Wiring
Table C-1. 10/100BASE-TX MDI and MDI-X Port Pinouts
Pin MDI-X Signal Name MDI Signal Name
1 Receive Data plus (RD+) Transmit Data plus (TD+)
2 Receive Data minus (RD-) Transmit Data minus (TD-)
3
Transmit Data plus (TD+) Receive Data plus (RD+)
6
Transmit Data minus (TD-) Receive Data minus (RD-)
4,5,7,8
Not used Not used
Note: The “+” and “-” signs represent the polarity of the wires that make
up each wire pair.
White/Orange Stripe
Orange
White/Green Stripe
Green
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
EIA
/
TIA 568B RJ-45 Wiring
S
tandard
10/100BASE-TX Straight-through Cable
End A
End B
Blue
White/Blue Stripe
Brown
White/Brown Stripe
White/Orange Stripe
Orange
White/Green Stripe
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
EIA/TIA 568B RJ-45 Wiring Standard
10/100BASE-TX Crossover Cable
End A
End B
Green
Blue
White/Blue Stripe
Brown
White/Brown Stripe