819
‐
1XRT
Serial
Cellular
Data
Modem
10
STANDARD
RS
‐
232
DE
‐
9
PINOUT
Table
1:
DE
‐
9
Pin
Out
Description
(Direction
is
DTE
relative
to
DCE)
Pin
Name
Direction
Description
1
CD
←
Carrier
Detect
2
RX
←
Receive
Data
3
TX
→
Transmit
Data
4
DTR
→
Data
Terminal
Ready
5
GND
System
Ground
6
DSR
←
Data
Set
Ready
7
RTS
→
Request
to
Send
8
CTS
←
Clear
to
Send
9
RI
←
Ring
Indicator
Figure
3:
RS
‐
232,
DB9
Pin
out
Diagrams
