Multitasking in a SubVI.

[labmaster]

I am programming some motor in X-Y translator.

X and Y are independent control channels each other.

Therefore, I want to move X-Y at the same time.

Without SubVI, I realized this by using two indepent sequence loops.

In making SubVI (only one but different paramters in main VI),

One axis(Y) was start to move just after completing the other's moving(X).

I am in LabVIEW 7.0.

Any helps?

[Britoa]

place a 0ms wait in both loops, this will tell the system that you can do other things. Otherwise, you will need a multiprocessor system, and use timed loops to handle it. (this is experience reading other people's responses to similar things on this forum, if someone wants to prove me wrong, have at it)

[Matt_W1]

I doubt a 0 ms wait is needed. And you don't need to use timed loops to take advantage of a multicore system. Most likely the original poster is using the same non reentrant vi for both axes. Since a non reentrant vi blocks any concurrent calls to itself (there is only one instance of the vi that is running at any instant). So you'll probably want to set the vi to have reentrant execution (note: that if your vi holds data between calls you might need to make some changes to it). You can set reentrant execution in the VI Properties under execution (this would be for the subvi). Another option would be to make a separate vi for each axis. You'll probably want to lookup reentrant in the LabVIEW docs to get an idea of what that setting does.

[Aashish_M]

Hi Labmaster,

Below are some links for X-Y motion examples;

-http://zone.ni.com/devzone/cda/epd/p/id/4406

-http://zone.ni.com/devzone/cda/epd/p/id/4428

-http://zone.ni.com/devzone/cda/epd/p/id/2559

-http://zone.ni.com/devzone/cda/tut/p/id/3161

Hopefully these help out.

[labmaster]

Thank you for your discussions.

Originally, I intend to give a question about reentrant property.

However, all were helpful to me to understand the variety of LV function.

Thanks again.