Siemens 6ES7540-1AD00-0AA0 - RS232 Interface Properties and Signals

Product overview
2.4 Properties of the RS232 interface
CM PtP RS232 BA communication module (6ES7540-1AD00-0AA0)
14 Manual, 01/2013, A5E03777472-01
2.4 Properties of the RS232 interface
Definition
The RS232 interface is a voltage interface used for serial data transmission.
Properties
Table 2- 2 The RS232 interface has the following properties and meets the following requirements:
Type Voltage interface
Front connector 9-pin sub-D male connector with screw lock
RS232 signals TXD, RXD, RTS, CTS, DTR, DSR, RI, DCD, GND; all signals isolated
against the backplane bus and load voltage
Max. data transmission
rate
19.2 kbps
max. cable length 15 m, cable type LIYCY 9 x 0.14
Standard DIN 66020, DIN 66259, EIA-RS 232C, CCITT V.24/V.28
RS232 signals
Table 2- 3 The table below shows the meaning of the individual RS232 accompanying signals.
Signal Designation Meaning
TXD Transmit Data Transmit data; transmit cable logically held to "1" by communication module in idle
state.
RXD Receive Data Receive data; receive cable logically held to "1" by communication partner in idle state.
RTS Request To Send Request to send
RTS set to "ON": Communication module ready to send; signals to the communication
partner that there is data ready to send
RTS set to "OFF": Communication module not ready to send
CTS Clear To Send Clear to send
CTS set to "ON": Signals "clear to send" to the communication partner
CTS set to "OFF": Signals "Not clear to send" to the communication partner
DTR Data Terminal Ready DTR set to "ON": Communications module switched on, ready for operation
DTR set to "OFF": Communications module not switched on, not ready for operation
DSR Data Set Ready DSR set to "ON": Communication partner signals "ready for operation"
DSR set to "OFF": Communication partner not switched on, not ready for operation
RI Ring Indicator Incoming call when connecting a modem
DCD Data Carrier Detect Carrier signal when connecting a modem. The communication partner signals with a
high level that it detects incoming data on the cable.