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Values are not propagating from a top level VI to its subVI

I have a top level motion control VI that uses a "Wait for Value Change" to trigger a subVI once a certain wire changes value. I have attached a few partial screenshots. 


fwd_rev_bool_type_def.jpg shows the type def in question at the bottom of the screenshot.


The "Jog Directions" input is connected to a type def named jog_momentarily.ctl (attached as jog_momentarily.png)


this is connected to a vi that taxes this same type def as input. This subVI that takes jog_momentarily as an input is kept inside of a Value Change control structure. See "jog_an_axis.png". 


For some reason this value is not propagating, when I input a true to forward by clicking on it at run time, The value present at the input of the subVI is still "False, False" as shown by the probe and block diagram screenshot "probe_subvi_input.png"


What could cause this value to not propagate to its subVI? Never ran into this before so am quite curious. 


Thank you



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Hi Dave,


do you know we cannot debug/edit/run images in LabVIEW?

What do you expect us to see in your images showing a tiny portion of your VIs?

Best regards,

using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
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The other thing to know is few of the most experienced participants on the Forum are using LabVIEW 2023.  A "best bet" is to "save for previous version" specifying LabVIEW 2019, or at most LabVIEW 2021.


Bob Schor

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