Rs232 Interface Of The Communications Module - Siemens SIMATIC ET 200SP Equipment Manual

Connecting

3.2 RS232 interface of the communications module

3.2 RS232 interface of the communications module
RS232 interface
The RS232 interface is a voltage interface used for serial data transmission.
The inputs and outputs are not isolated from each other. The inputs and outputs are
electrically isolated from the backplane bus.
Terminal assignment of the BaseUnit
Table 3- 1 RS232 connection
Terminal assignment of
the
BaseUnit of the communi-
cations module
Front view
20
Pin Designation
1 TXD Transmit Data
2 RXD Receive Data
3 RTS Request To Send
4 CTS Clear To Send
5 DTR Data Terminal Ready
6 DSR Data Set Ready
7 DCD Data Carrier Detect
8 RI Ring Indicator
9 GND Ground
10
Input/output Meaning
Output Transmit data
Input Receive data
Output Request to send
Input Clear to send
Output Data terminal ready
Input Data set ready
Input Received signal level
Input Incoming call
--- Shared ground reference
(ground)
CM PtP communications module (6ES7137-6AA01-0BA0)
Equipment Manual, 03/2021, A5E03790792-01