Example, Using references, Updating connection descriptions – Echelon LonWorks Network XML User Manual
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Using the XML Schema
or override components of the referenced object.
SubsystemName
Y
Y
On export, the subsystem name is reported
relative to the root subsystem of the export. See
Using References in this section for more
details.
On import, the name can be specified as either
an absolute path or a relative path.
DeviceName
Y Y Specifies
the
name of the application device of
the target NV/message tag.
FunctionalBlockName
Y
Y
Specifies the name of the functional block of the
target NV/message tag.
TargetName
Y
Y
The name of the target NV/message tag that is
connected to the current hub NV/message tag or
is to be added and connected to the current hub
NV/message tag on import.
Example
<Target>
<SubsystemName>$Subsystem1</SubsystemName>
<DeviceName>AI-1</DeviceName>
<FunctionalBlockName>AFB-1</FunctionalBlockName>
<TargetName>A1</TargetName>
</Target>
Using References
When defining connection targets, you must specify all the properties of the target NV/message tag,
which consists of the SubsystemName, DeviceName, FunctionalBlockName, and TargetName
properties. If one or more of these properties is unknown, you can define object references in the
target specification.
To define an object reference, you specify the Ref attribute with a value that can be used in connection
definitions to refer back to that object. For example, to create a reference for a subsystem object, use
the following syntax:
<Subsystem Action="CREATE_UNIQUE" Ref="TargetSub">.
When this XML statement is executed, the subsystem object and a reference to it named “TargetSub”
are created. If you define a connection target, you could now specify a reference to an application
device within that subsystem using the following syntax:
<Target>
<ReferenceName>TargetSub</ReferenceName>
<DeviceName>AO- 1</DeviceName>
<FunctionalBlockName>AFB- 1</LonMarkObjectName>
<TargetName>A1</TargetName>
</Target>
When using a reference name, you can override any of the Target properties by explicitly specifying
those properties in the target specification.
Updating Connection Descriptions
You can request that the connection description used for all connections involving a specific
NV/message tag hub be recomputed on import. To do this, append RecomputeCd="True" (
case-insensitive) to the opening <Targets> tag so that the Targets element is as follows:
<Targets RecomputeCd="True">
<Target>