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Owning Palette: Structures

Use the Timed Structures and VIs to control the rate and priority at which a timed structure executes its subdiagram, synchronize the start time of timed structures, create timing sources, and establish a hierarchy of timing sources.

Example

The VIs and functions on this palette can return Timed Loop Error Codes.

Palette Object	Description
Build Timing Source Hierarchy	Creates a hierarchy of timing sources based on the names you enter in timing source names.
Clear Timing Source	Stops and deletes the timing source you created or specified for use by another resource.
Create Timing Source	Creates a timing source you use as the timing source in the Timed Loop. Each timing source has its own unit of timing and/or start time and does not start until the first Timed Loop that uses the timing source starts. You must manually select the polymorphic instance you want to use.
Stop Timed Structure	Stops a Timed Loop or Timed Sequence structure you enter in name.
Synchronize Timed Structure Starts	Synchronizes the start of Timed Loops or Timed Sequence structures you enter in timed structure names by adding the names to the synchronization group you specify in synchronization group name.
Timed Loop	Executes one or more subdiagrams, or frames, sequentially each iteration of the loop at the period you specify. Use the Timed Loop when you want to develop VIs with multirate timing capabilities, precise timing, feedback on loop execution, timing characteristics that change dynamically, or several levels of execution priority. Right-click the structure border to add, delete, insert, and merge frames. If you use the Timed Loop in an FPGA VI, the loop executes one subdiagram at the same period as an FPGA clock.
Timed Sequence	A Timed Sequence structure consists of one or more subdiagrams, or frames, timed by an internal or external timing source that execute sequentially. A Timed Sequence structure executes each frame only once and, unlike a Timed Loop, does not repeat iterations. Use the Timed Sequence structure when you want to develop VIs that execute only once with precise timing, execution feedback, timing characteristics that change dynamically, or several levels of execution priority. Right-click the Timed Sequence structure border to add, delete, insert, and merge frames.

Example

Refer to the labview\examples\general\timedloop.llb for examples of using the Timed Structures and VIs.