Modem Cable; Rj45 Pin Assignments - 3Com SuperStack II 3C16987 User Manual

42 A B: P -
PPENDIX IN

Modem Cable

RJ45 Pin
Assignments
OUTS
9-pin to RS-232 25-pin
Switch 3300 SM
Cable connector: 9-pin female
Screen Shell
TxD 3
RxD 2
RTS 7
CTS 8
DSR 6
Ground 5
DCD 1
DTR 4
Pin assignments are identical for 10BASE-T and 100BASE-TX RJ45
connectors
Table 7 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
Signal
TxData +
TxData –
RxData +
Not assigned
Not assigned
RxData –
Not assigned
Not assigned
Screen
TxD
RxD
RTS
CTS
DSR
Ground
DCD
DTR
Function
Transmit data
Transmit data
Receive Data
Receive data