ThingFacet is a reusable TQL component that defines the software interactions with a "thing" and represent the "thing" in the software. A "thing" can be sensors, actuators, devices, or a particular aspect or function of a more complex machine. A ThingFacet has Attributes and Actions.
Attributes
Attributes are containers of values. They can be used for the following purposes:
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(4) Act as control variables - variable that can activate certain actions. They are called "actionable attributes". Actionable attributes are linked with one or more actions in the same ThingFacet by a modifier "KnownBy". For example: <Number Name="TempValue" KnownBy="SerialReadAction"/>
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