A.4.5 Write data

The COM UA Proxy converts all the ItemIds in the Write into valid NodeIds by replacing the ‘-’ with ‘=’. It converts the Value, Quality and Timestamp (VQT) to a DataValue structure as per the mapping in Figure A.17. and calls the OPC UA Write Service for the Value Attribute.

If the Write Service call fails or if there are errors for some of the Nodes, then the StatusCodes of these Nodes are mapped to the error code by the COM UA Proxy.

The mapping of the OPC UA Status code to OPC DA Write Error code (in the COM UA Proxy) is shown in Table A.9:

Table A.9 – OPC UA Write error code mapping
OPC UA Status Code OPC DA Error ID
Bad_TypeMismatchE_BADTYPE
Bad_OutOfMemoryE_OUTOFMEMORY
Bad_NodeIdInvalidE_INVALIDITEMID
Bad_NodeIdUnknownE_UNKNOWNITEMID
Bad_NotWritableE_BADRIGHTS
Bad_UserAccessDeniedE_ACCESSDENIED
Bad_AttributeIdInvalidE_UNKNOWNITEMID
Bad_WriteNotSupported E_NOTSUPPORTED
Bad_OutOfRangeE_RANGE