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Times a loop to execute on a specified interval. The VI executes at the rate specified by the value wired to the Count terminal. If an execution instance is missed, such as when the logic in the loop takes longer to execute than the specified interval, the Loop Timer returns immediately and establishes a new reference time stamp for subsequent calls. The Loop Timer differs from the Wait Until Next ms Multiple function, which wakes on a multiple of the wired in millisecond multiple. Details  

Dialog Box Options

Block Diagram Inputs

Block Diagram Outputs

Dialog Box Options

Parameter	Description
Counter Units	Unit of time the VI uses for the counter. 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	Specifies the time between loop iterations.

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.

Loop Timer Details

The first time the Loop Timer executes in a loop, it records the current time. The next time the Loop Timer executes, it adds Count to the initial time and waits until Count has elapsed from the initial recorded time. The Loop Timer does not wait the first time you call it in an FPGA VI. If you place the Loop Timer in a loop so that it can execute immediately when the loop starts, all the code parallel with the Loop Timer in the loop executes twice before Count elapses after the initial time. To prevent the code from executing twice before Count elapses, use a Flat Sequence structure or a Stacked Sequence structure with the Loop Timer in the first frame and the rest of the code in subsequent frames to ensure that the code for the first and subsequent iterations is properly timed.