3com 4500G Quick Setup Guide
80
A
PPENDIX
A: P
IN
-
OUTS
Modem Cable
RJ-45 to RS-232 25-pin
Ethernet Port RJ-45
Pin Assignments
Pin Assignments
10/100 and 1000BASE-T RJ-45 connections.
Table 10 Pin assignments
Screen
TxD
RxD
RTS
CTS
DSR
Ground
DCD
DTR
RxD
RTS
CTS
DSR
Ground
DCD
DTR
Screen
TxD
RxD
RTS
CTS
DSR
Ground
DCD
DTR
RxD
RTS
CTS
DSR
Ground
DCD
DTR
Shell
3
2
7
8
6
5
1
4
2
7
8
6
5
1
4
1
2
3
4
5
6
7
8
20
2
3
4
5
6
7
8
20
Switch 5500
Cable connector: RJ-45 female
Cable connector: RJ-45 female
RS-232 Modem Port
Cable connector: 25-pin male
Cable connector: 25-pin male
Pin Number
10/100
1000
Ports configured as MDI
1
Transmit Data +
Bidirectional Data A+
2
Transmit Data
−
Bidirectional Data A
−
3
Receive Data +
Bidirectional Data B+
4
Not assigned
Bidirectional Data C+
5
Not assigned
Bidirectional Data C
−
6
Receive Data
−
Bidirectional Data B
−
7
Not assigned
Bidirectional Data D+
8
Not assigned
Bidirectional Data D
−