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In this lecture, I'm going to show you how to use the R b injured or returned by exception, the RPG

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note is available down here under functions.

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What it does is that it will only pass changes to its output, changes of its input to its output.

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Its input does not change.

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Then it will not forward it to the output.

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So it's easier to demonstrate, deploy this flow and of God and inject note here, sending a one and

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another inject node, sending a two to my Arby node.

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So first I'm going to click on the one on the first debug node and you can see that its value did pass

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through to the output.

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Now I'm going to click on the same node again and again and again.

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You can see up here it says that this node is injected with trigged.

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But nothing reaches the output, and that's because and that's because there is no change between the

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existing value and the new value that is held inside the RV inhered, and therefore it does not pass

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through.

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But if I send it a two to different value, you can see that that is passing through.

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Can you send a few more twos again?

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And none of them passes through?

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I can go back to one and that is now passing through.

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And because I've got different values coming through the RBA, you know, those are being passed through.

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So it's pretty simple the way that it works.

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There's not that much configuration wise, at least in these properties.

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You can see that you've got a few choices of how you would like this node to handle change.

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The simplest one is to just block change unless the value actually changes.

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So I am actually using this specific node in my project so that my flow terrarium controller will only

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tell the ADENHART to start and stop the pump motor if its previous instruction was opposite to the current

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instruction.

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So that way I'm just saving a little bit of bandwidth there and making the process a bit more efficient.