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The element allows to get data from MODBUS RTU device and to write data to MODBUS RTU device.

Requests for management:

addvirtual - add a virtual sensor. Extra options are:

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• mb_addr - slave address of device on bus, decimal (1-255);
• mb_reg - register index for modbus function, hexademal string;
• mb_func - function code for modbus:
  • Read Coil Status (0x01);

  • Read Input Status (0x02);

  • Read Holding Register (0x03);

  • Read Input Register (0x04).

• mb_type - data type:
  

  1. 16 bits signed int;

  2. 16 bits unsigned int;

  3. 32 bits signed int;

  4. 32 bits unsigned int;

  5. 32 bits IEEE 754 floating point.

• mb_order - data ordering:
  

  1. low byte first, low word first;

  2. low byte first, high word first;

  3. high byte first, low word first;

  4. high byte first, high word first.

• mb_period - the polling period, seconds.

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• mb_addr - slave address of device on bus, decimal (1-255);
• mb_reg - register index for modbus function, hexademal string;
• mb_func - function code for modbus:
  • Write Single Coil (0x05);

  • Write Single Register (0x06).

• mb_wrval - writing value, integer.

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• k - user session ID;
• virtual_type - type of virtual sensor:
  • modbus rtu - for reading Modbus data;
  • modbus rtu write - for writing Modbus data.
• mb_addr - slave address of device on bus, decimal (1-255);
• mb_reg - register index for modbus function, hexademal string;
• mb_func - function code for modbus:
  • Read Coil Status (0x01);

  • Read Input Status (0x02);

  • Read Holding Register (0x03);

  • Read Input Register (0x04);

  • Write Single Coil (0x05);

  • Write Single Register (0x06).

• mb_type - data type (for reading only):
  

  1. 16 bits signed int;

  2. 16 bits unsigned int;

  3. 32 bits signed int;

  4. 32 bits unsigned int;

  5. 32 bits IEEE 754 floating point.

• mb_order - data ordering (for reading only):
  

  1. low byte first, low word first;

  2. low byte first, high word first;

  3. high byte first, low word first;

  4. high byte first, high word first.

• mb_wrval - writing value, integer (for writing only).

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If no error occurs, the writing test looks like:

If Modbus is disabled or not supported:

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