Product Description
1.4 Properties of the serial interface
PtP coupling and configuration of CP 340
Manual, 04/2011, A5E00369892-03
19
RS 232C signals
The table below shows the meaning of the RS 232C accompanying signals.
Table 1- 5
RS 232C interface signals
Signal
Designation
Meaning
TXD
Transmitted Data
Transmitted data; transmission line is maintained at logic "1" by the communication
processor in idle state.
RXD
Received Data
Received data; receive line must be maintained at logic "1" by communication
partner.
RTS
Request To Send
RTS "ON": Communication processor is ready to send.
RTS "OFF": Communication processor is not sending.
CTS
Clear to send
Communication partner can receive data from the communication processor. The
communication processor expects this signal in response to RTS "ON".
DTR
Data terminal ready
DTR "ON": Communication processor is active and ready for operation.
DTR "OFF": Communication processor is not active and not ready for operation.
DSR
Data Set Ready
DSR "ON": Communication partner is active and ready for operation.
DSR "OFF": Communication partner is not active and not ready for operation.
RI
Ring Indicator
Incoming call when connecting a modem
DCD
Data carrier detect
Carrier signal when connecting a modem
Содержание SIMATIC CP 340
Страница 6: ...Preface PtP coupling and configuration of CP 340 6 Manual 04 2011 A5E00369892 03 ...
Страница 10: ...Table of contents PtP coupling and configuration of CP 340 10 Manual 04 2011 A5E00369892 03 ...
Страница 186: ...Accessories and Order Numbers PtP coupling and configuration of CP 340 186 Manual 04 2011 A5E00369892 03 ...
Страница 190: ...Literature on SIMATIC S7 PtP coupling and configuration of CP 340 190 Manual 04 2011 A5E00369892 03 ...
Страница 200: ...Index PtP coupling and configuration of CP 340 200 Manual 04 2011 A5E00369892 03 ...