RJ-45
The RJ-45 connector is commonly used for network
cabling and for telephony applications. It's also used for
serial connections in special cases. Here's a look at it:
Pinout for Ethernet
Although used for a variety of purposes, the RJ-45
connector is probably most commonly used for 10Base-T and 100Base-TX
Ethernet connections.
Pin #
|
Ethernet 10BASE-T
100BASE-TX
|
EIA/TIA 568A
|
EIA/TIA 568B or AT&T 258A
|
1
|
Transmit +
|
White with green strip
|
White with orange stripe
|
2
|
Transmit -
|
Green with white stripe or solid green
|
Orange
with white stripe or solid orange |
3
|
Receive +
|
White with orange stripe
|
White
with green stripe |
4
|
N/A
|
Blue with white stripe or solid blue
|
Blue with white stripe or solid blue
|
5
|
N/A
|
White with blue stripe
|
White with blue stripe
|
6
|
Receive -
|
Orange with white stripe or solid
orange
|
Green with white stripe or solid
|
7
|
N/A
|
White with brown strip or solid brown
|
White with brown strip or solid brown
|
8
|
N/A
|
Brown with white stripe or solid brown.
|
Brown with white stripe or solid brown.
|
Because only two pairs of wires in the eight-pin RJ-45
connector are used to carry Ethernet signals, and both 10BASE-T and
100BASE-TX use the same pins, a crossover
cable made for one will also work with the other.
Also, please note that it is very important that a
single pair be used for pins 3 and 6. If one conductor from one
pair is used for pin 3 and a conductor from another pair is used for
pin 6, performance will degrade. See the following figure.
To learn more about Ethernet, check out Charles
Spurgeon's Ethernet Reference.
RJ-45 Pinout for RocketPort
The following chart shows the pinout for RJ-45
connectors used on certain RocketPort serial interface cards
(manufactured by Comtrol).
Pin |
Name/Description |
1 |
Request To Send |
2 |
Data Terminal Ready |
3 |
Ground |
4 |
Transmit Data |
5 |
Receive Data |
6 |
Data Carrier Detect |
7 |
Data Set Ready |
8 |
Clear To Send |
Pinouts for ISDN
Here's an ISDN BRI U port pinout for a Cisco 750
series router:
1 |
Not used |
2 |
Not used |
3 |
Not used |
4 |
U interface network connection (tip) |
5 |
U interface network connection (ring) |
6 |
Not used |
7 |
Power (pass-through to S connector) |
8 |
Ground (pass-through to S connector) |
The following chart shows the pinout for RJ-45
connectors used on certain ISDN S/T interfaces. For more info,
see ANSI T1.605.
Pin |
Color |
Name/Description |
1 |
White/Orange |
N/A |
2 |
Orange |
N/A |
3 |
White/Green |
Receive+ |
4 |
Blue |
Transmit + |
5 |
White/Blue |
Transmit - |
6 |
Green |
Receive - |
7 |
White/Brown |
-48VDC (optional) |
8 |
Brown |
-48VDC Return (optional) |