Hi all, I would like an event structure to execute only on the first value change. I currently have it set to execute on the value change of a boolean. I am only interested in what happens the first time the boolean changes; however, it changes multiple times during a single execution of my vi. Is there any way to limit the event structure so that it only executes on the first value change? I have attached the relevant part of my VI. Thank you in advance for any assistance you will be able to provide. Thank you, yp21

Do the comparison before the case structure, eliminating the lower shift register. If you swap the cases, you don't need to invert the OR operation. You still have that 28.5714ms wait constant. waits are integers. Your outer loop has an infinite loop rate, consuming 100% CPU in the FALSE case Code still looks clumsy. Use a state machine and eliminate the inner loop.

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Execute Event structure only on first value change

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Do the comparison before the case structure, eliminating the lower shift register.
If you swap the cases, you don't need to invert the OR operation.
You still have that 28.5714ms wait constant. waits are integers.
Your outer loop has an infinite loop rate, consuming 100% CPU in the FALSE case
Code still looks clumsy. Use a state machine and eliminate the inner loop.

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Your state machine suggestion was perfect. It does exactly what I want now. Thank you all for your suggestions and ideas. I definitely feel more confident with doing things like this.