Counting only once when a case structure is true in a while loop

[repel89]

Hi. First time posting here so do pardon me. I have tried searching for answers in the forums along with attempting the solution myself but to no avail.

Here is the problem. I am trying to collect voltage signals via the DAQ assistant. When a certain threshold voltage is reached, the "true" case would run. I am currently using the shift register along with the while loop hence the output number "numerical 2" would increase as the while loop runs. However, I only want to register a single case as long the voltage is above is above the threshold.

Eg. When the voltage is above 3V for some time, it registers only a 1. Then the voltage might dip below 3V. The next time the voltage is above 3V again it would register a 2. So on and so forth. I have attached an image of my block diagram below. Thanks for the help!

[crossrulz · Accepted solution]

Keep the status of the threshold reached in a shift register.  Perform an AND with the inverse of the value in the shift register and your new threshold detection.  The result of the AND goes into your case structure.

EDIT:  I just threw together this example.  I used a Feedback Node since it would be cleaner.

[repel89]

Hey. Thanks for the quick reply and assistance. The solution worked out for me. Cheers! 🙂