Communication Protocol
SiOne Page
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Communication Protocol
The device is equipped with RS-485 industrial interface, MODBUS RTU protocol and can only work on the network as SLAVE.
Remember to install terminators (resistor 120 ... 240 Ohm) between lines A and B at the beginning and the end of the RS-485 network.
Transmission Parameters
Transmission parameters for connection with the SiOne transmitter:
Baud rate:
Configured via jumpers (9600, 19200, 38400, 57600)
Data format:
8
Stop bits:
1
Parity:
none
Transmission control:
none
MODBUS address:
Configured via jumpers (1…32)
Communication Frame
Communication with the device in the MODBUS RTU protocol is done on a "question-answer" basis. The MASTER initiates a
frame for writing or reading data, and the device (SLAVE) returns a response with a parameter or a write acknowledgment of the
parameter. The structure of the communication frame for the MODBUS RTU protocol is shown below.
ADR FUNC DAT1
DAT2
…
DATn
CRC16
