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Catalyst 2940 Switch Hardware Installation Guide
OL-6157-01
AppendixB Connectors and Cabl es
Connector Specifications
10/100/1000 Ports
The 10/100/1000 Ethernet port on the Catalyst 2940-8TT-S switch uses a standard RJ-45 connector.
Figure B-3 shows the pinout.
FigureB-3 RJ-45 Pinouts for 10/100/1000 Port

Connecting to 10BASE-T and 100BASE-TX Devices

When connecting the ports to 10BASE-T and 100BASE-TX devices, such as servers, workstations, and
routers, you can use a two or four twisted-pair, straight-through cable wired for 10BASE-T
and100BASE-TX. FigureB-6 sh ows the two twisted-pair, straight-through cable schematics. Figure B-8
shows the four twisted-pair, straight-through cable schematics.
When connecting the ports to 10BASE-T- and 100BASE-TX devices, such as switches or repeaters, you
can use a two or four twisted-pair, crossover cable. Figure B-7 shows the two twisted-pair, crossover
cable schematics. Figure B-9 shows the four twisted-pair, crossover cable schematics.
You can use Category 3, 4, or 5 cabling when connecting to 10BASE-T devices. You must use Category
5 cabling when connecting to 100BASE-TX devices.

Connecting to 1000BASE-T Devices

When connecting the ports to 1000BASE-T devices, such as servers, workstations, and routers, you must
use a four twisted-pair, Category 5, straight-through cable wired for 10BASE-T, 100BASE-TX, and
1000BASE-T. FigureB-10 shows the straigh t-through cable schematics.
When connecting the ports to other devices, such as switches or repeaters, you must use a four
twisted-pair, Category 5, crossover cable. FigureB-11 shows the crossover cable schematics.
Note Be sure to use a four twisted-pair, Category 5 cable when connecting to a 1000BASE-T device.
Note Use a straight-through cable to connect two ports only when one port is designated with an X. Use a
crossover cable to connect two ports when both ports are designated with an X or when both ports do
not have an X.
12 3 4 5 6 7 8
Pin Label
1
2
3
4
5
6
7
8
TP0+
TP0-
TP1+
TP2+
TP2-
TP1-
TP3+
TP3-
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