A.3.2.2 Value

The data values in the DA server are represented as Variant data type. The COM UA Wrapper converts them to the corresponding OPC UA DataType. The mapping is shown in Table A.2:

Table A.2 – DataTypes and mapping

Variant Data Type

(In DA server)

OPC UA Data type Mapping in COM UA Server

(DataValue structure)

VT_I2Int16
VT_I4Int32
VT_R4 Float
VT_R8Double
VT_BSTRString
VT_BOOLBoolean
VT_UI1Byte
VT_I1SByte
VT_UI2UInt16
VT_UI4UInt32
VT_I8Int64
VT_UI8UInt64
VT_DATEDouble
VT_DECIMALDecimal
VT_ARRAYArray of OPC UA types

.