Reading Variable from simple Server shows timestamp but no value.

[h2k_toy]

Hello,

i'm greenhorn to this topic and i have problems getting started. I downloaded the Demo-SDK and craeated a model using the UAModeler.

Basically i can not find a simple example that uses a model generated with the UaModeler. This would be helpfull.

For evaluation I created a model with a folder and 3 variables of type UInt32, String and Boolean.

I use the generated code and succeeded to view the model with the 3 variables using the UaExpert tool.

I override the NodeManager method like:

Code: Select all

        public override DataValue ReadAttribute(RequestContext context, NodeAttributeHandle nodeHandle)
        {
            if(object.Equals(nodeHandle.NodeId.Identifier, VariableIds.WeldTask_JobNumber.Identifier))
            {
                return new DataValue(new Variant((UInt32)1));
            }
            else
            {
                return base.ReadAttribute(context, nodeHandle);
            }
        }

This is the only change i made to the generated code.

The method is being called as expected, when i click on the node in the UaExpert.
I can identify the requested variable and return a value = 1

The timestamp is showed in the ua expert but the values is always 0.

I tried the same with the boolean and string variable - corresponding results with timestamps successfully transmitted but values shows default.

Question:
- Can somebody explain why i receive a timestamp but no values at all?

[h2k_toy]

I just checked the model and can find no errors.

The DataType of JobNumber is "UInt32":

Code: Select all

    
    <UAVariable DataType="UInt32" NodeId="ns=1;i=6010" BrowseName="1:JobNumber" AccessLevel="3">
        <DisplayName>JobNumber</DisplayName>
        <References>
            <Reference ReferenceType="HasTypeDefinition">i=63</Reference>
            <Reference ReferenceType="HasComponent" IsForward="false">ns=1;i=5003</Reference>
        </References>
    </UAVariable>

The data type is aliased in the model:

Code: Select all

        <Alias Alias="UInt32">i=7</Alias>

And the nodeids are as intended.

Code: Select all

<UAObject NodeId="ns=1;i=5003" BrowseName="1:WeldTask">
  <!-- ... -->
</UAObject>

I'd like to post the full model but it's too big...

The only thing which appeared strange to me is that the namespace changes from 1 to 2 when i load the model into .NET objects. But a collegue said this is normal. (?) This is why i compare only the nodeid.Identiifer in the ReadAttribute method. However, this seems not to be the problem but maybe somebody can clarify what's going on here.

[Support Team]

Hello,

Please override the Read-Method as shown in the examples. The method ReadAttribute is not called by the BaseNodeManager implementation.

[h2k_toy]

Hi Thank you very much, that helped.