Global Variable question

[skap]

Hi all,

I have a basic global variable question. I am running a vi that is monitoring the voltage of a battery. A sub-vi is called which performs an operation which lasts approximately 30 seconds. During the 30 seconds I would like to monitor the battery voltage, however, my main VI is waiting for the sub-VI to finish. Is there any way for the Main VI voltage-indicator to be updated through the sub-VI?

Thanks for the help,

[Al_S]

You need more than a global: you need to use a VI server. Without using a VI server, your calling VI will pause while the sub-VI is executing. So just having a global won't help because the calling VI won't do anything with it until the sub-VI is done (unless you use a VI server).

Take a look at the VI Server examples that ship with Labview. In Labview 6.1 menus, goto Help>> Find Examples >> Search, then search for VI Server.

[skap]

Thanks alot, actually I found a really easy and basic fix for this type of issue....I am just running a while loop in parallel with the main VI that is monitoring the voltage. It is a cheap and dirty way to get the result I need, but I'll keep your answer in mind when this method doesn't work.

Thanks again

[Al_S]

The loop in your main VI will still pause while any sub-VI is running.

[Olivier Zimmermann]

Al S a écrit:

>The loop in your main VI will still pause while any sub-VI is running.
>
>

It will not ...unless you go for it, like telling the subvi to execute
as a "subroutine".

In the simplest scheme parallel tasks WILL be executed in a parallel
way. Disconnected while loops do work that way.

This is a good reason why instrumentation programmers do like to do it
with LabVIEW... 🙂

oz