RS232 Pinout
What is RS232 Pinout?
Rs-232 or Recommended Standard 232 is used for binary serial communication between devices like modems, printers, phones and other PC peripherals. The RS-232 standard was introduced in 1962 and it was initially intended for data communication between a DTE (Data Terminal Equipment) and DCE (Data Circuit-terminating Equipment). Since the introduction of the USB standard the usage of RS-232 has decreased considerably, only a few PC are still equipped with this standard (especially industrial ones).
RS232 pinout is the definition or function of each DB9 and BD25 socket pins.
RS232 Pinout DB9
A DB9 socket is a electrical connector used in serial communication. The RS232 pinout for a DB9 socket is composed of 9 pins, arranged on two parallel rows. There are two types of DB9 connectors: male DB9 connectors, also called plugs and female DB9 connectors, also called sockets.
RS232 Pinout for DB9 connectors
|
Pin
|
Signal
|
In/Out
|
Description
|
|
1
|
DCD
|
In
|
Data Carrier Detect
|
|
2
|
RxD
|
In
|
Receive Data
|
|
3
|
TxD
|
Out
|
Transmit Data
|
|
4
|
DTR
|
Out
|
Data Terminal Ready
|
|
5
|
GND
|
-
|
Ground
|
|
6
|
DSR
|
In
|
Data Set Ready
|
|
7
|
RTS
|
Out
|
Request To Send
|
|
8
|
CTS
|
In
|
Clear To Send
|
|
9
|
RI
|
In
|
Ring Indicator
|
| RS232 Pinout DB9 | RS232 Pinout DB9 Male and Female Connectors |
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RS232 Pinout DB25 Serial and Parallel port
Like the name says this connector has 25 pins placed on two rows. There are two types of DB25 connectors: male and female. DB25 along with DB35 are also used in parallel communication, but there the pinout is different then the serial RS232 pinout.
Serial Port – RS232 Pinout – DB25
|
Pin
|
Signal
|
Description
|
|
1
|
PG
|
Protective Ground
|
|
2
|
TxD
|
Transmitted Data
|
|
3
|
RxD
|
Received Data
|
|
4
|
RTS
|
Request To Send
|
|
5
|
CTS
|
Clear To Send
|
|
6
|
DSR
|
Data Set Ready
|
|
7
|
GND
|
Common Ground
|
|
8
|
DCD
|
Data Carrier Detect
|
|
20
|
DTR
|
Data Terminal Ready
|
|
22
|
RI
|
Ring Indicator
|
Parallel Port – RS232 Pinout – DB25
|
Pin
|
Signal Name
|
Direction
|
Inverted
|
|
1
|
Strobe
|
In/Out
|
Yes
|
|
2
|
Data0
|
Out
|
No
|
|
3
|
Data1
|
Out
|
No
|
|
4
|
Data2
|
Out
|
No
|
|
5
|
Data3
|
Out
|
No
|
|
6
|
Data4
|
Out
|
No
|
|
7
|
Data5
|
Out
|
No
|
|
8
|
Data6
|
Out
|
No
|
|
9
|
Data7
|
Out
|
No
|
|
10
|
Ack
|
In
|
No
|
|
11
|
Busy
|
In
|
Yes
|
|
12
|
Paper-Out
|
In
|
No
|
|
13
|
Select
|
In
|
No
|
|
14
|
Linefeed
|
In/Out
|
Yes
|
|
15
|
Error
|
In
|
No
|
|
16
|
Reset
|
In/Out
|
No
|
|
17
|
Select-Printer
|
In/Out
|
Yes
|
|
18-25
|
Ground
|
-
|
-
|
| RS232 Pinout DB25 | RS232 Cable |
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