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Initializing a variable once on the RT side of a RIO

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Having trouble initializing a flip flop VI i wrote

It starts up in whatever state it wants. 


How can i force a particular state?

Its just an SR latch


Thanks in advance 


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Hi there, Thanks 

So when i wrote the VI i notices it automatically populated a feedback node

If i tried to delete it , i could not compile. 

So the feedback node is my answer but need to understand how to use it. 

I know my Q output to initialize to false and my Q not to be high

I will read the link you sent me. Thank you


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My only other issue is, I am triggering my Latch reset with a falling edge trigger.


The clock that is running the latch is only running at the speed of a while loop. 

It is causing me to miss the falling edge sometimes. Do you have any suggestions


Setting the Feedback node like this to false did not work

I need to find a way to guarantee it



Edited by rscott9399

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If you don't want to use a feedback node, another option is using a local variable (see example below)

It sounds like you're trying to process losslessly. If that's the case, you usually need some sort of buffer. In this example, I use the event queue as my buffer.


RS Latch Local.png

RS Latch Event.png

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