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Regarding the LabVIEW dataflow model

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Hello everyone,


I have a question regarding the LabVIEW dataflow model. Please have a look at the attached screenshot which contains a part of my VI. The question is if the VISA Open (circled in red in the Picture) will be waiting for both VISA Resource Name and Error data before implementing its function, or it will be started immediately whatever comes in first?


Just to prevent some comments, I understand that I can try to track the VI implementation with "Highlight Execution" option - and I did it - but as my VI is a big one and I control by it some expensive devices, I don't want to ruin them without the complete understanding. From my tryings, it looks like it waits for all wired incomes before starting the implementation.


Thanks a lot for the time and help.

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Message 1 of 3
Accepted by topic author Yevh

Yes, all LabVIEW functions/vis will wait for all wired inputs to be available before attempting to do its function.



Message 2 of 3

Dataflow Basics.  "...a node executes only when data is available at all of its input terminals and supplies data to the output terminals only when the node finishes execution."


If you take that sentence (fragment) ultra-literally, you can predict how 99% of LabVIEW code will execute.  (Which includes "I don't know which will execute first".)  And structures are considered nodes (although what is inside of them still follows dataflow principles).

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Message 3 of 3