13-2. RS-232C Connector

 

 

 

 

 

Pin No.

Signal name

Direction

 

Function

1

F-GND

—

Frame ground

2

TXD

OUT

Transmission data

3

RXD

IN

Receive data

4

RTS

OUT

Same as DTR signal.

5

N/C

 

Not used

6

DSR

IN

STAR Mode

 

 

 

Status of this signal is not checked.

 

 

 

ESC/POS Mode

 

 

 

In DTR/DSR communication mode, indicates whether

 

 

 

data receive from host is enabled or disabled.

 

 

 

Space: Receive enabled

 

 

 

Mark: Receive disabled

 

 

 

(except when transmitting data by DLE EOT, and GS a)

 

 

 

This signal is not checked in the X-ON/X-OFF com-

 

 

 

munication mode.

7

S-GND

—

Signal ground

8~19

N/C

 

Not used

20

DTR

OUT

STAR Mode

 

 

 

Indicates whether data receive from host is enabled or

 

 

 

disabled.

 

 

 

1) DTR/DSR Communication Mode

 

 

 

Space when receive is enabled.

 

 

 

2) X-On/X-Off Communication Mode

 

 

 

Always space, except during following condi-

 

 

 

tions:

 

 

 

•

Period between reset and communication ena-

 

 

 

 

bled

 

 

 

•

During self printing

 

 

 

ESC/POS Mode

 

 

 

Indicates whether data receive from host is enabled or

 

 

 

disabled.

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