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Modem cable, Rj45 pin assignments – 3Com 16985ua.bk User Manual

Page 40

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40

A

PPENDIX

B: P

IN

-

OUTS

Modem Cable

9-pin to RS-232 25-pin

RJ45 Pin
Assignments

Pin assignments are identical for 10BASE-T and 100BASE-TX RJ45
connectors

Screen

TxD

RxD
RTS

CTS
DSR

Ground

DCD
DTR

Screen

TxD

RxD
RTS

CTS
DSR

Ground

DCD
DTR

Shell

3

2
7

8
6

5

1
4

1

2
3

4
5

6

7
8

20

Switch 3300 MM
Cable connector: 9-pin female

RS-232 Modem Port
Cable connector: 25-pin male

Table 6 Pin assignments

Pin Number

Signal

Function

Ports configured as MDI

1

TxData +

Transmit data

2

TxData –

Transmit data

3

RxData +

Receive Data

4

Not assigned

5

Not assigned

6

RxData –

Receive data

7

Not assigned

8

Not assigned

16985ua.bk Page 40 Thursday, September 7, 2000 9:15 AM