Dte pinout, Dce pinout – Rockwell Automation 1747-L40 SLC 500 Fixed Hardware Style User Manual
Page 127

Appendix C
RS-232 Communication Interface
C–4
DTE Pinout
Channel 0, which the 5/03 processor has, is configured as DTE. The pinouts
are the same as the 9–pin AT port.
DTE 9 pinout
Signal is
Equivalent
DTE 15 pinout
Equivalent
DTE 25 pinout
1 -DCD Data Carrier Detect
Input
8
8
2 -RXD Received Data
Input
3
3
3 -TXD Transmitted Data
Output
2
2
4 -DTR Data Terminal Ready
Output
11
20
5 -COM Common Return (Signal Ground)
Shared
7
7
6 -DSR Data Set Ready
Input
6
6
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
Signal is
Equivalent
DCE 25 pinout
1 -DCD Data Carrier Detect
Output
8
2 -RXD Received Data
Output
3
3 -TXD Transmitted Data
Input
2
4 -DTR Data Terminal Ready
Input
20
5 -COM Common Return (Signal Ground)
Shared
7
6 -DSR Data Set Ready
Output
6
7 -RTS Request to Send
Input
4
8 -CTS Clear to Send
Output
5
9 -RI
Ring Indicator
Output
22
Important: DCE signal names are viewed from a DTE perspective. For
example, TXD is a DTE output and also a DCE input.