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LabVIEW NXG Multi Read SystemLink Tag in Web VI

I am running a web VI (gviweb) and I'm using SystemLink tags.  I am trying to use "Multi Read.gvi" for reading a number of SystemLink tags, which is faster than reading them individually.  I am finding that my data comes back out of order relative to the order of the tags.  Within "Multi Read.gvi", there's a subVI for "Sort by Session"  What is the methodology for this VI and what's the easiest way to use "Multi Read" and get the data in my desired order?

 

I am using LabVIEW NXG 3.1 and my SystemLink Tag service version is 19.0

 

 

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Do you have a small example project, or screenshots you can provide? And is the order off relative to a Write function? Or to how they appear on your SystemLink Tag Viewer?

 

Brandon Nguyen | Product Support Engineer | National Instruments R&D

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I'm not using the SystemLink software (like the Tag Viewer).  I'm using the SystemLink VI's in LabVIEW NXG.  (Someone moved this question to this forum, not sure why.)

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Do you have an example project that shows the behavior? Additionally, could you provide the NXG version?

 

I'd expect the tag output of the Multi Read VI to maintain the same order as the 'tags in' input. 

 

Brandon Nguyen | Product Support Engineer | National Instruments R&D

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I'm working on getting an example to you. 

 

I'm in NXG 3.1.  

 

In "Multi Read.gvi", I noticed that there's a comment "Note: Not using a concatenating tunnel due to a known issue with NXG web VIs".  Can you give me any detail on what that issue might be?  

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It looks like there's an issue with my tag names.  If they end in 1, 2, or 3 (which is appended in a loop), things work.  If they end in RT, Avg3, or Avg10, there seems to be an issue.

 

VI is LV2018.

 

I can't attach a gviweb for some reason.  

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You can probably zip up and attach the project. 

 

That's pretty odd - if you look at the tag input to the Multi Read, is it in the order you expect? 

 

Brandon Nguyen | Product Support Engineer | National Instruments R&D

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