An OPC-UA Attribute Point is a connectivity point that represents an OPC Unified Architecture (OPC-UA) attribute on a node.
For operations listed below, following classes are used for the point itself, the operation parameters and operation arguments:
Operation | Point Type | Parameters Type | Arguments Type |
Read | UAAttributePoint Class | UAAttributePointReadParameters Class | UAAttributePointReadArguments Class |
Subscribe | UAAttributePointSubscribeParameters Class | UAAttributePointSubscribeArguments Class | |
Write | UAAttributePointWriteParameters Class | UAAttributePointWriteArguments Class |
You can use following type aliases for this point type:
In order to describe the point and its subscription parameters, use the following sequence:
EndpointDescriptorString, NodeId [, [AttributeId] [, SamplingInterval]]
Where:
If the point or parameters differ from the default in other properties, the friendly topic syntax cannot be used.
For valid symbolic values of the AttributeId, see UAAttributeId Enumeration Fields.
"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer", "nsu=http://test.org/UA/Data/;i=11218"
"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer", "nsu=http://test.org/UA/Data/;i=11218", "DataType"
"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer", "nsu=http://test.org/UA/Data/;i=11218", , "5000"
The XML topic syntax is capable to fully describe the point and parameters. It is currently not documented, and is subject to change.