Datakom D-500 MK2, User Manual

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D-500 MK2 User Manual Firmware V-6.3
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The unit offers the possibility of MODBUS communication through below carriers:
-RS485 serial port, with adjustable baud rate between 2400 and 115200 bauds
-MODBUS-TCP/IP through Ethernet port (100Mb)
-MODBUS-TCP/IP through GPRS (85/42kb), client mode through Rainbow Scada only
The MODBUS properties of the unit are:
-Data transfer mode: RTU
-Serial data: selectable baud rate, 8 bit data, no parity, 1 bit stop
-Modbus-TCP/IP: Ethernet 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 2 bytes (16 bits). A larger data structure will contain multiple registers.
The Modbus communications requires a slave address to be assigned to each device in the Modbus
network. This address ranges between 1 and 240 and allows the addressing of different slave devices in
the same network.
This chapter is a brief description of the Modbus properties of
the controller. For a complete documentation please use “500
Modbus
Application Manual”
Devices using Modbus-TCP/IP with different IP or port
addresses may use any slave address. It is advised to set
these slave addresses to the default setting which is 1.
Each device in the same RS-485 serial network must be
assigned a different slave address. Otherwise the Modbus
communications will not be performed.
35. MODBUS COMMUNICATIONS