Serial (DB25) connector

#Computer#Serial Interfaces

Very common PC serial port.

25 pin D-SUB MALE connector pin-out & layout

25 pin D-SUB MALE connector  at the computer

PinNameDirDescription
1SHIELD-Shield Ground
2TXD-->Transmit Data
3RXD<--Receive Data
4RTS-->Request to Send
5CTS<--Clear to Send
6DSR<--Data Set Ready
7GND-System Ground
8CD<--Carrier Detect
9n/c- 
10n/c- 
11n/c- 
12n/c- 
13n/c- 
14n/c- 
15n/c- 
16n/c- 
17n/c- 
18n/c- 
19n/c- 
20DTR-->Data Terminal Ready
21n/c- 
22RI<--Ring Indicator
23n/c- 
24n/c- 
25n/c- 
Note: Direction is DTE (Computer) relative DCE (Modem).
Note: Do not connect SHIELD(1) to GND(7).

Serial (Amiga) connector

Serial (DB9) connector