Serial Programming Guide for POSIX Operating Systems(4)

Appendix A, Pinouts

RS-232 Pinouts

     Figure  - RS-232 Connector

                      

Table 12 - RS-232 Signals

Pin

Description

Pin

Description

1

Earth Ground

14

Secondary TXD

2

TXD - Transmitted Data

15

Transmit Clock

3

RXD - Received Data

16

Secondary RXD

4

RTS - Request To Send

17

Receiver Clock

5

CTS - Clear To Send

18

Unassigned

6

DSR - Data Set Ready

19

Secondary RTS

7

GND - Logic Ground

20

DTR - Data Terminal Ready

8

DCD - Data Carrier Detect

21

Signal Quality Detect

9

Reserved

22

Ring Detect

10

Reserved

23

Data Rate Select

11

Unassigned

24

Transmit Clock

12

Secondary DCD

25

Unassigned

13

Secondary CTS

 

 

RS-422 Pinouts

 

                                 

             

Pin

Description

Pin

Description

1

Earth Ground

14

TXD+

2

TXD- - Transmitted Data

15

Transmit Clock-

3

RXD- - Received Data

16

RXD+

4

RTS- - Request To Send

17

Receiver Clock-

5

CTS- - Clear To Send

18

Unassigned

6

DSR - Data Set Ready

19

RTS+

7

GND - Logic Ground

20

DTR- - Data Terminal Ready

8

DCD- - Data Carrier Detect

21

Signal Quality Detect

9

Reserved

22

Unassigned

10

Reserved

23

DTR+

11

Unassigned

24

Transmit Clock+

12

DCD+

25

Receiver Clock+

13

CTS+

 

 

RS-574 (IBM PC/AT) Pinouts(公头)

 

 

                 

Pin

Description

Pin

Description

1

DCD - Data Carrier Detect

6

Data Set Ready

2

RXD - Received Data

7

RTS - Request To Send

3

TXD - Transmitted Data

8

CTS - Clear To Send

4

DTR - Data Terminal Ready

9

Ring Detect

5

GND - Logic Ground

 

 

SGI Pinouts

          

              Pin

Description

Pin

Description

1

Earth Ground

6

DSR - Data Set Ready

2

TXD - Transmitted Data

7

GND - Logic Ground

3

RXD - Received Data

8

DCD - Data Carrier Detect

4

RTS - Request To Send

9

DTR - Data Terminal Ready

5

CTS - Clear To Send

 

 

 

Appendix B, ASCII Control Codes

 

ASCII中的控制字符如下

             

Name

Hex

Name

Hex

Name

Hex

NUL

00

SOH

01

STX

02

ETX

03

EOT

04

ENQ

05

ACK

06

BEL

07

BS

08

HT

09

NL

0A

VT

0B

NP,FF

0C

CR

0D

SO

0E

SI

0F

DLE

10

XON,DC1

11

DC2

12

XOFF, DC3

13

DC4

14

NAK

15

SYN

16

ETB

17

CAN

18

EM

19

SUB

1A

ESC

1B

FS

1C

GS

1D

RS

1E

US

1F