D-1. RS-232C Connector
Signal
Pin No.
name
1
FG
Frame ground
2
TXD
Send data
3
RXD
Receive data
4
RTS
Request to send
5
–
6
DSR
Data set ready
7
SG
Signal GND
8
–
9
–
10
–
11
–
12
–
13
–
Appendix D: Serial Interface
I/O
Function
direction
OUT
IN
OUT
IN
13
12
11
10
9
8
25
24
23
22
21
<Viewed from Connector Surface>
Signal
Pin No.
name
14
–
15
–
16
–
17
–
18
–
19
–
20
DTR
Data terminal ready
21
–
22
–
23
–
24
–
25
INIT
7
6
5
4
3
20
19
18
17
16
15
– 96 –
I/O
Function
direction
OUT
Reset
IN
2
1
14