sub vi refnum

[chillem]

I have the attached VI that reads a file and generates a table of devices.  Code that is not shown then updates the table with measurement data.  There are several different files of devices so I would like to convert this into a sub VI. When I do this, I get the file and page start inputs and also the page1 output table.  I also get a table input which is a refnum.  What do I need to put in the main VI in order to be able to display page1 on the main front panel?  The refnum help files are not very clear on how to do this.

[Ajskrim · Accepted solution]

Hi chillem,

That refnum is reference to your front panel object. You are using implicit property nodes to edit your table during the execution and you can do that, only in the same VI. At the moment you create a subvi, LabVIEW changes those property nodes to explicit linked and gives you a reference to the object (your table Page 1) which you can then drive into the subvi. If you just select everything except the controls and indicators (inputs and outputs) on your block diagram and click on Create SubVI, LabVIEW will do everything instead of you and it will work for you out of the box.

More on the Explicitly vs Implicitly linked property nodes here:

Difference Between Implicitly and Explicitly Linked Property Node

Hope this helps.

[chillem]

Thanks a lot.  This is very useful.  I often make sub VIs directly from a labview source but occasionally I take old code into a new project without putting the old code into the new project and then making a sub VI.