Wait Express VI

Owning Palette: Execution Control Express VIs and Structures

Requires: DSP Module, FPGA Module, or Real-Time Module

Delays for a certain time interval before the output data dependence becomes valid.

(Real-Time Module) The Wait Express VI waits the specified count time and then returns the value of a free running counter. When the Wait Express VI executes, it sleeps and blocks the execution of other code running in the same thread.

Details  

Dialog Box Options

Block Diagram Inputs

Block Diagram Outputs

Add to the block diagram

Find on the palette

Dialog Box Options

Parameter	Description
Counter Units	Unit of time the VI uses for the counter. Note  (Windows) The Windows operating system supports only millisecond resolution. If you select a µSec or Tick resolution under Windows, the VI does not provide exact timing and instead provides an approximation that averages to the requested time over the course of the timing interval. Windows does not support resolutions under one millisecond and rounds them up to one millisecond. Ticks—Sets the counter units to a single clock cycle, the length of which is determined by the clock rate for which the VI is compiled. µSec—Sets the counter units to microseconds. mSec—Sets the counter units to milliseconds.
Size of Internal Counter	Specifies the maximum time a timer can track. To save space on the FPGA, use the smallest Size of Internal Counter possible for the FPGA VI.

Block Diagram Inputs

Parameter	Description
Count	The time spent in the component.

Block Diagram Outputs

Parameter	Description
Tick Count	Returns the value of a free running counter at the time the VI wakes up. A free running counter rolls over when the counter reaches the maximum of Size of Internal Counter specified in the configuration dialog box.

Wait Details

If you do not have the FPGA, Real-Time, or DSP modules, you can use the Wait (ms) function instead.

Note  (Real-Time Module, Windows) When the Wait Express VI runs inside a timed structure or a VI set to time-critical priority, it blocks the execution of all other code in the same timed structure or VI because timed structures and time-critical VIs are single-threaded. In all other cases, the Wait Express VI sleeps while other code in the calling VI runs in parallel on separate threads.

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