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Boolean Edge Detection

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Hi,

 

I can't find a way to detect when my boolean button gets a value from :

- 0 --> 1 (positive)

- 1 --> 0 (negative)

 

I think it is something with flank detection. But I don't know how to detect it.

 

Sorry for my English.

Thanks!

 

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Solution
Accepted by topic author Joran

Depending on what you want to do this should be a reasonably straightforward task.

 

Your options are:

1. Use a feedback node to hold the old value and perform a not equal (!=) check between the old version and new version each loop

2. Use a shift register to hold the old value and perform a not equal (!=) check between the old version and new version each loop

3. If you have 2017, you can use the VIM  "Is Value Changed" which contains a feedback node to perform this check

4. If you have openG installed there is a vi called "Data Changed" that performs the same functionality

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I can move on now 😉

Thank you for the quick reply !

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Solution
Accepted by topic author Joran

Hi joran,

 

5. Use PtByPt-BooleanCrossing...

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
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I would have never found that by my own 😉

 

Thank you very much !! 

 

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