Modem Cable; Ethernet Port Rj-45 Pin Assignments - 3Com 4500G Getting Started Manual

80 A A: P -
PPENDIX IN

Modem Cable

Ethernet Port RJ-45
Pin Assignments
OUTS
RJ-45 to RS-232 25-pin
Switch 5500
Cable connector: RJ-45 female
Screen Shell
TxD 3
RxD 2
RTS 7
CTS 8
DSR 6
Ground 5
DCD 1
DTR 4
10/100 and 1000BASE-T RJ-45 connections.
Table 10 Pin assignments
Pin Number
Ports configured as MDI
1
2
3
4
5
6
7
8
RS-232 Modem Port
Cable connector: 25-pin male
1
2
3
4
5
6
7
8
20
10/100
Transmit Data +
Transmit Data −
Receive Data +
Not assigned
Not assigned
Receive Data −
Not assigned
Not assigned
Screen
TxD
RxD
RTS
CTS
DSR
Ground
DCD
DTR
1000
Bidirectional Data A+
Bidirectional Data A−
Bidirectional Data B+
Bidirectional Data C+
Bidirectional Data C−
Bidirectional Data B−
Bidirectional Data D+
Bidirectional Data D−