RS232 vs ITU-T V.24 Signal Names

There are unfortunately a lot of different terms/names used for serial interfaces, depending on which context/spec you are looking at.

This table provides a mapping of the most common signals between different specs:

Common Name RS232 ITU-T V.24 Direction Description
GND AB 102 - Signal/System Ground
TXD BA 103 DTE->DCE Transmitted data
RXD BB 104 DTE<-DCE Received data
RTS CA 105 DTE->DCE Request to Send
CTS CB 106 DTE<-DCE Clear to Send
DSR CC 107 DTE<-DCE Data Set Ready
DTR CD 108/2 DTE->DCE Data Terminal Ready
DCD CF 109 DTE<-DCE Data Carrier detect
- - 113 DTE->DCE Transmitter signal element timing (DTE source)
- - 114 DTE<-DCE Transmitter signal element timing (DCE source)
- - 115 DTE<-DCE Receiver signal element timing (DCE source)
RI CE 125 DTE<-DCE Ring Indicator
- - 133 DTE->DCE Ready for receiving
  • DTE: Data Terminal Equipment (Computer/Terminal)
  • DCE: Data Communications Equipment (Modem/TA)

Full ITU V.24 table

Updated by laforge 10 days ago · 5 revisions

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