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  3. QPlatform.ModbusDriver
  4. VariableType
  5. Modbus tag

Modbus tag

BrowseName: ModbusTag
SuperType: Tag (Tag)

Object that represents a Modbus PLC tag.

Properties

Name

BrowseName

DataType

Description
Memory area

MemoryArea

ModbusMemoryArea

PLC memory location in which to read/write the tags.
Maximum length

MaximumLength

Int32

(string data only) Maximum number of characters in the string.
Register number

NumRegister

UInt16

Address in the memory location in which to read/write the tags.
Coil number

NumCoil

UInt16
Discrete input number

NumDiscreteInput

UInt16
Bit offset

BitOffset

UInt32

Position of the memory area register from which to start reading/writing. Position 0 of the Holding register (starting position) corresponds to register 4001.
Quality

Quality

Quality

(Inherited from Tag)
Operation code

OperationCode

TagOperationCode

(Inherited from Tag)
Array update mode

ArrayUpdateMode

TagArrayUpdateMode

(Inherited from Tag)
Original data type

OriginalDataType

NodeId

(Inherited from Tag)