Hardware Description
7
Manual Documentation Number EIR405-T – 0109m
www.bb-elec.com
www.bb-europe.com
RJ-45 Pin Assignments
Pin Number
Assignment
1 Tx+
2 Tx-
3 Rx+
6 Rx-
Note
“+” and “-” signs represent the polarity of each wire pair.
All ports on the EIR405-T support automatic MDI/MDI-X operation, you can use
straight-through cables (See Figure below) for all network connections to PCs or servers,
or to other switches or hubs. In straight-through cables, pins 1, 2, 3, and 6, at one end of
the cable, are connected straight through to pins 1, 2, 3 and 6 at the other end of the cable.
The table below shows the 10BASE-T / 100BASE-TX MDI and MDI-X port pin outs.
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-)
Straight Through Cable Schematic
