Download RS-232 Communication Interface

212
RS-232 Communication Interface
DTE 9 Pinout
Signal is Equivalent
Equivalent
DTE 15 Pinout DTE 25 Pinout
Pin
Description
7
RTS Request to Send
Output
4
4
8
CTS Clear to Send
Input
5
5
9
NC No Connection
Input
22 (RI Ring
Indicator)
DCE Pinout
Devices such as a modem are DCE. The pinouts on these terminals
are wired to interface with DTE.
DCE 9 Pinout
Equivalent DCE 25
Pinout
Pin
Description
1
DCD Data Carrier Detect
Input
8
2
RXD Received Data
Input
3
3
TXD Transmitted Data
Output
2
4
DTR Data Terminal Ready
Output
20
5
COM Common Return (Signal Ground)
Shared
7
6
DSR Data Set Ready
Input
6
7
RTS Request to Send
Output
4
8
CTS Clear to Send
Input
5
9
RI Ring Indicator
Input
22
IMPORTANT
Publication 1747-UM011G-EN-P - June 2008
Signal is
DCE signal names are viewed from a DTE perspective. For
example, TXD is a DTE output and also a DCE input.