Hi Fabrizio,
I am not very familiar with MAC but with the LabVIEW Hacker and Linx in Windows you have to send a configuration command through the Tools/labVIEW Hacker menu. This may take a few minutes depending on the speed of your interface. You will probably have to select the board you are working with and a few other things to get it to work. When this is working correctly and LabVIEW is connected to Linx, the TX/RX leds on the board should flash very fast for as long as it is connected.
When I set up a Linx connected Arduino, I normally start out with a sequence in LabVIEW that sets the inital parameters of communication with controls so that I can quickly and easily change settings if needed. I then check to see that I am getting connected to the board using the error vi to compare the numeric codes to the connected codes. Once it is connected, turn on a boolean to indicate that that sequence has connected properly prior to moving to the next section of code.
I also set up a stop boolean in a structure like a while loop that encloses the code that I want to run. Using a stop boolean in a structure is a cleaner way to stop your vi than hitting the stop button on the toolbar. Often I have had difficulty reinitializing the vi to connect with the Arduino board after hitting the stop button on the toolbar. Once I implemented the stop boolean in the structure, stopping and restarting the vi was much smoother.
Hope this helps,
Guardsmanblue
