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What Modbus function codes is supported by by WRITE_VAR /READ_VAR function block of SoMachine.

WRITE_VAR/ READ_VAR function block sends modbus request function code depending on selection made for "object type" input.

WRITE_VAR sends standard modbus request with function code 16 ( 16#10) means write multiple register if object type is selected as 00 ( Holding register -16 bits)

WRITE_VAR sends standard modbus request with function code 15 ( 16# F) means write multiple coils if object type is selected as 02 ( Internal Bit or Digital ouput coil -1 bit)


READ_VAR receive standard modbus request with function code 01 ( 16#01) means read coils  if object type is selected as 02 ( Internal Bit or Digital output coil -1 bit)

READ_VAR receive standard modbus request with function code 02 ( 16#02) means read digital inputs  if object type is selected as 01 ( Digital input -1 bit)

READ_VAR receive standard modbus request with function code 03 ( 16#03) means read holding registers if object type is selected as 00 ( Holding register -16 bits)

READ_VAR receive standard modbus request with function code 04 ( 16#04) means read input registers if object type is selected as 03 ( Input register -16 bits)

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