RS-232 Layouts

RS-232 Layout for 9 Pin Connector


Diagram for DE-9 female connector (mating face)	Diagram for DE-9 female connector (soldering face)

The following table shows the signals of a 9 pin RS-232.

9 pin RS-232.
Pin	Signal	Name
2	Received Data	RX
3	Transmitted Data	TX
4	Data Terminal Ready	DTR
5	Signal Ground	GND
6	Data Set Ready	DSR
7	Request To Send	RTS
8	Clear To Send	CTS

Only signals used for regular RS-232 communication are shown.

RS-232 Layout for 25 Pin Connector


Diagram for DB-25 male connector (mating face)	Diagram for DB-25 male connector (soldering face)

This table shows the signals of a 25 pin RS-232 connector. There are 25 connections in the complete specification, but it is very likely to find less than half of these in a given interface.

25 pin RS-232.
Pin	Signal	Name
3	Received Data	RX
2	Transmitted Data	TX
20	Data Terminal Ready	DTR
7	Signal Ground	GND
6	Data Set Ready	DSR
4	Request To Send	RTS
5	Clear To Send	CTS

Only signals used for regular RS-232 communication are shown.