Problems with communicating with Arduino

[moons657]

Hey everybody. I am trying to do a full project in college using Arduino interfacing with LabVIEW to acquire voltage levels such as sound and move stepper motors accordingly. I have the full VI built but I am having a problem with the Arduino not being able to communicate back to LabVIEW at the start of the program. When you run the program with highlighting enabled, LabVIEW tries to communicate with the Arduino and it does not receice anything back from it. I have tried redownloading the base firware to the Arduino and also checking the Com ports are working and all that seems fine. The funny thing is that it might work one time then work for a couple of time after. I dont know what to do to be honest?

Anyone have any ideas on possible problems with the Arduino not communicating with LabVIEW intermittently?

I appreciate any help anybody can give me.

Keith

[Nathan_B.]

At what point (in which VI) are you seeing the behavior you described with highlighting on?  Are you able to run the blink example successfully without any issues?  Also, can you attach your VI to your next post so that we can see if there is anything that might be obvious to us.

[Vass]

I had same problem, it might sound strange but try creating a stop button within the loop in your VI and always stop your VI by clicking this button, do not stop your VI by clicking the abort execution. If you still cant communicate restart Labview.

I hope this helps.

[Nathan_B.]

This is good advice and something that I always recommend because if you use the stop execution button or don't allow the close VI to run, there is a chance that the COM port will not be freed for the next time you try to initialize the Arduino.

[moons657]

Hey everyone. Thanks for all the advice. I solved the problem by reinstalling the firmware to the Arduino and now it works perfectly.