Buttons as input in subvis

[govindsankar]

Hi,

I have done a code in which, I have created a subvi and used it in another vi. But I have 3 inputs as push buttons in the subvi and I have included them as input terminals and in the main vi, I placed 3 buttons to those 3 input terminals. But when I run the program and push the button in the main vi, the button inside subvi is not turning on. I did not know this before. Is there any way to solve this. Kindly do reply. Thanking You.

[pincpanter]

Post your vi's. It's hard to give an answer without them.

[GerdW]

Hi govindsankar,

you probably have to THINK DATAFLOW to solve the problem!

You can expect more specific answers after posting your VIs…

[Gregory]

Hi Govind,

At the moment the SubVI is called, it will take the current values at all of its inputs. If you do not call your SubVI, the inputs will never be updated. 

[Gregory]

Also, if the button is set to any of the latching mechanisms, it will not visually appear like the SubVI button is pressed (on the front panel).

[altenbach]

Is the subVI interactive or does it return immediately? We clearly need to see some code.

[paul_cardinale]

My wild guess is that you've done something like this:

and that you're expecting that while the subVI is running, it should be able to read changes in the value of the button in the calling VI.  That won't happen.  When the subVI starts executing, it receives the value of the button at that time.  It does not receive updates if the button value changes.

[altenbach]

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@paul_cardinale wrote:

My wild guess is that you've done something like this:

and that you're expecting that while the subVI is running, it should be able to read changes in the value of the button in the calling VI.  That won't happen.  When the subVI starts executing, it receives the value of the button at that time.  It does not receive updates if the button value changes.

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If the subVI does not contain a loop and returns immediately (but keeps the panel open), the FP will update whenever the button is read in the caller. Thus my earlier question.