Using a network published variable to control an event structure on the RT side of a RIO

[rscott9399]

Hi all

 

Trying to use a network published variable to control the event structure of something in an RT loop of a rio project. 

When i try and add an event, it wont let me have access to that variable.

Any ideas?

Maybe create a local variable?

 

 

 

[Jordan Kuehn]

If you have the DSC module this may be what you are looking for.

https://forums.ni.com/t5/Example-Programs/Creating-a-Value-Change-Event-for-Shared-Variables/ta-p/3528947?profile.language=en

[smithd]

13 hours ago, rscott9399 said:

Hi all

Trying to use a network published variable to control the event structure of something in an RT loop of a rio project. 

When i try and add an event, it wont let me have access to that variable.

Any ideas?

Maybe create a local variable?

Generally RT code doesn't have a UI, and as mentioned you have to use a special add-on to use events with shared variables. The usual equivalent is to use a messaging tool to handle communication and generate events in your RT code. I personally use HTTP and/or websockets since its free and there are many clients out there. I believe there is a tcp handler for drjdp's messenger lib (https://sine.ni.com/nips/cds/view/p/lang/en/nid/213091), actor framework has a networking addon, and for quick and dirty, AMC (https://www.ni.com/example/31091/en/) works.

 

To put it another way, where you might use a UI event (queue) structure on a windows machine, you would typically use asynchronous I/O (eg tcp, udp, serial) to feed a queue on the rt system.