How to interface a running VI.

[knowledge_is_power]

Hello all,

I'm looking for the best solution in interfacing an actively running VI (GUI).

For example, I currently have a LabVIEW VI that serves as both a GUI and driver for the hardware it's controlling. This 'driver' VI serves as the user interface for manual operation but is also controlled by an external VI that I will refer to as 'Command' vi. 'Command' vi has a reference to 'driver' vi and accesses the front panel to manipulate the values on it's terminals; therefore causing an event trigger. The event trigger starts the processes required for setting/attaining values on the hardware. Once the the 'driver' vi finishes doing what is reuested the 'Command' vi stops execution while the 'driver' VI remains connected to the hardware and continues running.

You may be asking why do this? The reason is that I'm interfacing this actively running VI directly from teststand and the normal method of calling a VI from teststand requires that the VI execute and finish for the data to be returned. In this case I have a seperate VI in which i make calls to from TestStand.

So as I just discussed my current approach involves accessing the running VI's front panel and manipulating it's controls through property nodes. Is there a better, more efficient, easier way to do this?

Thanks!

[WishKebab]

Hi knowledge_is_power, 

    As far as I'm aware, property and invoke nodes are the most straightforward way to accomplish what you are trying to do. 

[knowledge_is_power]

Thanks WishKabob,

is there any information on the NI website specifically related to this process? I kind of used my knowledge of LabVIEW to create my own solution.

[WishKebab]

Hi kip, 

The following posts/documents might prove useful for your application:

VI server between 2 Vis in 2 different projects

Creating a VI Server Application

Controlling Front Panel Objects Programmatically from a SubVI

Updating a Control or Indicator of a Top Level VI from a SubVI

Let me know if you have any questions about implementation of the VI server.  Best of luck!