check for empty visa resource?

[nyc_(is_out_of_here)]

When I am developing the VI at my desk and not a the test station PC, the VISA resource name is empty.

Once the VI is moved to the test station PC, the user can select a VXI board.

How do I make sure the user has selected a VISA resource before continuing?

I can wire a Comparision to check for Empty String, and that works. But is there any method that I should use?

[Omar_II · Accepted solution]

Try "Not A Number/Path/Refnum"

Or just try to open the Refnum and trap for any errors and loop back to have the user select again.

[D_Biel]

Additionally, you can limit the selectable items by interface type. Right-click VISA Resource Name Control and select I/O Name Filtering.