LabVIEW Data Value Reference Wire Breaking When Used With a Feedback Node and Case Structure

Updated Sep 23, 2021

Reported In

Software

  • LabVIEW

Issue Details

Initialising a New Data Value Reference with any non-double data type inside the "True" case of a Case Structure and passing this through a feedback node back into the case structure breaks the wire:
LabVIEW_w4cipQz2pc.png

 

Solution

This is reported in bug 1632130. There are several workarounds available to use if wishing to use Data Value References in an FGV form:
  • The issue does not appear if the Data Value Reference is created in the "False" case. Reverse the cases and use a "Not" function to the logic entering the case structure
LabVIEW_T2AHQ18FaN.png
  • The issue does not appear if using shift registers inside a one-cycle while loop:
LabVIEW_rYnJa7HUrI.png
  • This issue can also appear when using a numeric-choice or string-choice case structure. In this scenario, drag the case that creates the Data Value Reference to the top of the case list in the drop-down menu with the Right-Click -> "Rearrange Cases" button. It does not matter which case is the default case.
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