Serial (PC 9)

From HwB

Also known as EIA/TIA 574.



9 PIN DE-9 MALE at the Computer.


9 PIN DE-9 FEMALE at the Cable.

Pin Name RS232 V.24 Dir Description
1 (D)CD CF 109 Arrowl.png (Data) Carrier Detect
2 RXD BB 104 Arrowl.png Receive Data
3 TXD BA 103 Arrowr.png Transmit Data
4 DTR CD 108.2 Arrowr.png Data Terminal Ready
5 GND AB 102 Arrow.png System Ground
6 DSR CC 107 Arrowl.png Data Set Ready
7 RTS CA 105 Arrowr.png Request to Send
8 CTS CB 106 Arrowl.png Clear to Send
9 RI CE 125 Arrowl.png Ring Indicator


  • Direction is DTE (Computer) relative DCE (Modem).
  • RS232 column is RS232 circuit name.
  • V.24 column is ITU-TSS V.24 circuit name.


RS232 Diagram.svg