Various RS232 Pinouts

- RS232 DB9 Pinout, DTE (terminal, computer...)

PinNameDirection
1 DCD (Data carrier detect)Input
2 RD (Receive data)Input
3 TD (Transmit data)Output
4 DTR (Data terminal ready)Output
5 GND (Ground)N/A (Power)
6 DSR (Data set Ready)Input
7 RTS (Request to send)Output
8 CTS (Clear to send)Input
9 RI (Ring Indicator)Input

- PC motherboard rs232 connector pinout (2x5 header)

PinNameDirection
1 DCD (Data carrier detect)Input
2 DSR (Data set Ready)Input
3 RD (Receive data)Input
4 RTS (Request to send)Output
5 TD (Transmit Data)Output
6 CTS (Clear to send)Input
7 DTR (Data terminal Ready)Output
8 RI (Ring Indicator)Input
9 GND (Ground)N/A (Power)


Electrical info:

Logic 0 (space) +5...+15Volts
Logic 1 (mark) -5...-15Volts


RTS/CTS Hardware handshaking info:

to be done...

Written by Raphaël Assénat <raph@raphnet.net>
Using various sources of information from the net, manuals, and books.