Protocols - RACOM RipEX User Manual

RTS/CTS (Request To Send / Clear To Send) hardware flow control (handshake) between the DTE
(Data Terminal Equipment) and RipEX (DCE - Data Communications Equipment) can be enabled
in order to pause and resume the transmission of data. If RX buffer of RipEX is full, the CTS goes
down.
NOTE: RTS/CTS Flow control requires a 5-wire connection to the COM port.
■ Protocol*
List box: None, Async Link, C24, Cactus, Comli, DF1, DNP3, IEC101, ITT Flygt, Modbus, PR2000,
Profibus, RDS, RP570, Siemens 3964(R), Slip, UNI
Default = None
Each SCADA protocol used on serial interface is more or less unique. The COM port daemon per-
forms conversion to standard UDP datagrams used in RipEX Radio network. Each protocol has its
individual configuration parameters, which are described in separate Help page (accessible from
configuration light box Protocol - click on Protocol, then on Help). Protocol "None" simply discards
any data received by the COM port or from the network, which means that the respective COM port
is virtually disconnected from the RipEX.

7.3.5. Protocols

Fig. 7.5: Menu Protocols COM
■ Generally
Each SCADA protocol like Modbus, DNP3, IEC101, DF1 etc. has its unique message format, most
importantly its unique way of addressing of remote units. The basic task for protocol utility is to
check whether received frame is within protocol format and it is not corrupted. Most of the SCADA
protocols are using some type of Error Detection Codes (Checksum, CRC, LRC, BCC, etc.) for data
integrity control, so RipEX calculates this code and check it with the received one.
© RACOM s.r.o. – RipEX Radio modem & Router
Advanced Configuration
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