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.9. 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.39:

Table A.39– OPC UA Write error code mapping

OPC UA Status Code

OPC DA Error ID

Bad_TypeMismatch

E_BADTYPE

Bad_OutOfMemory

E_OUTOFMEMORY

Bad_NodeIdInvalid

E_INVALIDITEMID

Bad_NodeIdUnknown

E_UNKNOWNITEMID

Bad_NotWritable

E_BADRIGHTS

Bad_UserAccessDenied

E_ACCESSDENIED

Bad_AttributeIdInvalid

E_UNKNOWNITEMID

Bad_WriteNotSupported

E_NOTSUPPORTED

Bad_OutOfRange

E_RANGE