A+ Study Guide: Device Configuration & Port Settings

DB-9M

Function

Abbreviation

1

Data Carrier Detect

CD

2

Receive Data

RD or RX or RXD

3

Transmitted Data

TD or TX or TXD

4

Data Terminal Ready

DTR

5

Signal Ground

GND

6

Data Set Ready

DSR

7

Request To Send

RTS

8

Clear To Send

CTS

9

Ring Indicator

RI