check if port is opened

[bartonekJ]

Hi, i'd like to control arduino from animation package called Autodesk Maya. I'm also quite new to python, so forgive me stupid questions, please.

Lets say I'm running this script in Maya:

from pyfirmata import ArduinoMega, util
port = "COM3"
board = ArduinoMega(port)

and then some "for loop"

But if i'll run that script again, maya retuns: SerialException: could not open port 'COM3': WindowsError(5, 'Access is denied.')

So id like to check if COM3 is already connected.I've tried following code, but it's obviously nonsense:

port = "COM3"
if ArduinoMega(None):     # is there some bolean which tells me if i've already assigned board to COM3 or not ? 
     board = ArduinoMega(port)
     print board
else:
     print "already connected"

Is there some way how to do it, please ?

[tino]

You should probably properly close the serial connection at the end of the script. If you exit the script there is not way to maintain a state that would tell you there is already a connection.

You'll want to call board.exit() at the end of the script, or when exiting.