Making An Ethernet Twisted Pair Cable - HP FlexFabric 12900E series Installation Manual

Table 69 RJ-45 MDI interface pinouts
Pin
1
2
3
4
5
6
7
8
Table 70 RJ-45 MDI-X interface pinouts
Pin
1
2
3
4
5
6
7
8
To ensure normal communication, the pins for sending data on one port should correspond to the
pins for receiving data on the peer port. When both of the ports on the two devices are MDI or MDIX,
a crossover Ethernet cable is needed. A cross-over cable connects devices of the same type. When
one port is MDI and the other is MDIX, a straight-through Ethernet cable is needed. A
straight-through cable connects devices of different types.
An RJ-45 Ethernet interface with MDI/MDIX autosensing enabled can automatically negotiate pin
roles. The 12900E RJ-45 Ethernet interfaces support MDI/MDIX. By default, MDI/MDIX is enabled
on a port.

Making an Ethernet twisted pair cable

Cut the cable to length with the crimping pliers.
1.
Strip off an appropriate length of the cable sheath. The length is typically that of the RJ-45
2.
connector.
Untwist the pairs so that they can lie flat, and arrange the colored wires based on the wiring
3.
specifications.
Cut the top of the wires even with one another. Insert the wires into the RJ-45 end and make
4.
sure the wires extend to the front of the RJ-45 end and make good contact with the metal
contacts in the RJ-45 end and in the correct order.
Crimp the RJ-45 connector with the crimping pliers until you hear a click.
5.
10Base-T/100Base-TX
Signal Function
Tx+ Send data
Tx- Send data
Rx+ Receive data
Reserved N/A
Reserved N/A
Rx- Receive data
Reserved N/A
Reserved N/A
10Base-T/100Base-TX
Signal Function
Rx+ Receive data
Rx- Receive data
Tx+ Send data
Reserved N/A
Reserved N/A
Tx- Send data
Reserved N/A
Reserved N/A
1000Base-T
Signal
BIDA+
BIDA-
BIDB+
BIDC+
BIDC-
BIDB-
BIDD+
BIDD-
1000Base-T
Signal
BIDB+
BIDB-
BIDA+
BIDD+
BIDD-
BIDA-
BIDC+
BIDC-
112
Function
Bi-directional data cable A+
Bi-directional data cable A-
Bi-directional data cable B+
Bi-directional data cable C+
Bi-directional data cable C-
Bi-directional data cable B-
Bi-directional data cable D+
Bi-directional data cable D-
Function
Bi-directional data cable B+
Bi-directional data cable B-
Bi-directional data cable A+
Bi-directional data cable D+
Bi-directional data cable D-
Bi-directional data cable A-
Bi-directional data cable C+
Bi-directional data cable C-