[Greg McKaskle]

How do the subVIs run? If one calls another calls another, like much of WPILib, then the typical approach is to pass the data in and out using a parameter. This is what happens if you select some code and use Edit>>Create SubVI from Selection.

If the VIs are going to loop forever, or for a long time, similar to how Periodic tasks or Vision does, then you need another communication mechanism. Globals are the one I'd start with. Be careful to write to a given global in only one loop and read it in the others, or you will start to see race conditions.

Greg McKaskle