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LabVIEW
Why the waveform in Main program does not show up?
Your main program will receive data once the subVI stops. Your subVI never stops.
In order to stop the subVI via it's FP stop button, it's front panel must be open. Right-click on its icon in main.vi and select "subVI node setup". Select "show front panel when called and close afterwards". Once the subVI closes, the last point is shown in the chart of the main VI. This is probably not hat you really wanted.
It seems to me that you are a bit confused about the details of dataflow.
There are methods to update the main graph in realtime, but they are quite a bit more advanced. What exactly are you trying to do?
In order to stop the subVI via it's FP stop button, it's front panel must be open. Right-click on its icon in main.vi and select "subVI node setup". Select "show front panel when called and close afterwards". Once the subVI closes, the last point is shown in the chart of the main VI. This is probably not hat you really wanted.
It seems to me that you are a bit confused about the details of dataflow.
There are methods to update the main graph in realtime, but they are quite a bit more advanced. What exactly are you trying to do?
I thought I already explained that. You call a subVI that never stops which updates its own hidden waveform graph forever. This subVI cannot produce any output to the main VI until it finishes. It never finishes!
Dataflow dictates that:
A node cannot execute until all inputs have received data.
A node cannot produce output until it finishes.
You have a few options, two are shown in the attached modification:
(1) get rid of the while loop in the subVI and place it in the main VI. Now the subVI gets called successively, always immediately returning a value. (This is the correct and recommended way).
(2) Feed a reference to the chart of the main VI to the subVI, then update the main graph via property writes. This is not very efficient but can be useful in a limited set of circumstances. The implementation is also currently incomplete, because the subVI cannot be stopped.
In any case, please put some small wait in each of your loops. Else they spin as fast as possible, consuming all CPU and making your computer sluggish.
Dataflow dictates that:
You have a few options, two are shown in the attached modification:
(1) get rid of the while loop in the subVI and place it in the main VI. Now the subVI gets called successively, always immediately returning a value. (This is the correct and recommended way).
(2) Feed a reference to the chart of the main VI to the subVI, then update the main graph via property writes. This is not very efficient but can be useful in a limited set of circumstances. The implementation is also currently incomplete, because the subVI cannot be stopped.
In any case, please put some small wait in each of your loops. Else they spin as fast as possible, consuming all CPU and making your computer sluggish.
