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R s 2 3 2 – RF Neulink NL900PRO User Manual

Page 7

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C H A P T E R 3 - S E R I A L I N T E R F A C E

5


R S 2 3 2

RS232 is a single-ended data transmission protocol. The RS232 signals are represented by voltage levels
with respect to a system common (power/logic ground). The “idle” state (MARK) has the signal level
negative with respect to common, and the “active” state (SPACE) has the signal level positive with respect to
common.

F i g u r e 3 : R S 2 3 2 D I P S w i t c h S e t t i n g s

ON

ON

1 2 3

4 5 6

1 2 3

4 5 6

Normal RS232 Operation

Forced 9600 Mode

T A B L E 3 : N L 9 0 0 P R O R S 2 3 2 P I N O U T

D B 9 P I N

S I G N A L N A M E

I / O

D E S C R I P T I O N

D E T A I L S

1

DCD

O

Data Carrier Detect

Carrier Detect Signal.
Connects to DSR (pin 6).

9

5


6

1


Female DB9




2

TXD

O

Transmitted Data

Serial Data from modem

to Host.

3

RXD

I

Received Data

Serial Data from Host to

Modem.

4

DTR

I

Data Terminal Ready

Used to determine if

modem is ready for

operation.

5

GND

-

Ground

Ground

6

DSR

O

Data Set Ready

Connects to DCD (pin 1).

7

RTS

I

Request To Send

Provides RTS Flow Control

8

CTS

0

Clear To Send

Provides CTS Flow Control

9

NC

-

No Connect

No Connect