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The unit offers MODBUS in the following forms:
-RS485 serial port, adjustable data transfer rate between 2400 and 115200 baud
-MODBUS-TCP/IP over the Ethernet port (10/100Mb)
-MODBUS-TCP/IP over GPRS Network (85/42kb), valid only with Rainbow Scada.
MODBUS features of the unit:
-Data transfer mode: RTU
-Serial data: adjustable baud rate, 8 bit data, no parity, 1 bit stop
-Modbus-TCP/IP: Ethernet 10/100Mb or GPRS Class 10.
-Supported functions:
-Function 3 (read multiple registers)
-Function 6 (write single register)
-Function 16 (write multiple registers)
Each register consists of 2bytes (16 bits). Larger data structures are provided with multiple registers.
Each device on the Modbus communication network must have a distinct Modbus address. The unit
supports addresses in the range 1-240.
MODBUS TCP/IP devices registered to different IP or port
numbers may use the same addresses.
Every device on the RS-485 serial network must have a distinct
address. Otherwise, Modbus communication will not function.
22. MODBUS COMMUNICATION
