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Looking for some help with getting my case study to only print result once.

Hey.

 

I'll apologies if this has been answered before but I have been unable to find a solution for this.

 

I'm using labview 11

 

What I want to happen is that when my voltage spike comparison is activated (True) the system outputs a time stamped message saying voltage spike and when the output is false the message becomes voltage spike end. I want them to occur just once so I can have a log of the events on my front panel

Voltage spike

Voltage spike ends

Voltage Spike

Voltage Spike ends

 

At the moment what happens is that I get constant stream of my output text depending if the condition is true or false.

I have tried several things but nothing to date has worked and I have also attempted to search for a solution but again no luck.

 

I would really appreciate it if anyone has any ideas how to solve this or has come across it before.

 

Regards

 

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You need to store the boolean value of the voltage spike in a shift register.  Compare the current value of the boolean spike with the previous value.  If the values are different, then execute your current case structure.  If they are the same, then don't execute your case structure.

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Hi,

 

use "boolean crossing" function:

check.png

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
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