Piedinature - Pinouts
Serial (PC 25 Pin)

25 PIN D-SUB MALE (At the computer)

25 PIN D-SUB MALE at the computer.

Pin	Name	Dir	Description
1	SHIELD	-	Shield Ground
2	TXD	OUT	Transmit Data
3	RXD	IN	Receive Data
4	RTS	OUT	Request to Send
5	CTS	IN	Clear to Send
6	DSR	IN	Data Set Ready
7	GND	-	System Ground
8	CD	IN	Carrier Detect
9	n/c	-
10	n/c	-
11	n/c	-
12	n/c	-
13	n/c	-
14	n/c	-
15	n/c	-
16	n/c	-
17	n/c	-
18	n/c	-
19	n/c	-
20	DTR	OUT	Data Terminal Ready
21	n/c	-
22	RI	IN	Ring Indicator
23	n/c	-
24	n/c	-
25	n/c	-

Note: Direction is DTE (Computer) relative DCE (Modem).
Note: Do not connect SHIELD(1) to GND(7).

Piedinature - PinoutsSerial (PC 25 Pin)