global serialObject
global myVar1, myVar2, myVar3

on startMovie
  	clearglobals
  -- variables for setting up the xtra.
  -- Fill in your own values from the email
  -- that you get from the licence registrar:
    
  -- fill in your email address below (see physicalbits.com for details)
  programmerName = "youremail@some.com"
  serialnum  =  "xxxx-xxxx-xxxx-xxxx"   -- physicalbits.com will mail you this number
  licenseLength = 90
  
    -- fill in the name of your serial port below (e.g. COM1 on Windows):
  mySerialPort = "/dev/cu.USA19QW191P1.1"

  
  
  	-- make a new instance of the xtra (mac OSX)
  	openxlib the pathname & "serialXtra.osx"

  	-- use this line instead for Windows:
  	-- openxlib the pathname & "serialXtra.xtr"
  	
  	
  	serialObject =  new (xtra "SerialXtra", programmerName, serialnum, licenseLength ) 
  
  	-- check that it has been created correctly     
  	if objectP( serialObject ) then
    	put serialObject 
  	else
    	alert("Instance not valid")
  	end if
  
--	open the serial port:
  	serialObject.openPort(mySerialPort)

  
  	-- set the data rate, start bits, etc:
  	serialObject.setProtocol(9600, "n", 8, 1)
end

on stopMovie  
  -- dispose of the xtra and close the xtra file
  serialObject.closePort()
  set serialObject to 0
  closeXlib 
end 

on exitFrame
  	doSerial
  	go the frame
end 

on doSerial
  -- see if the port’s been opened:
  If serialObject.isPortOpen() then
    If serialObject.charsavailable() = 0 then
      --send a byte to ask for data
      SerialObject.writeChar("A")	
    End if
    
    If SerialObject.charsAvailable() >=3 then      
      --first byte sent by microcontroller:
      MyVar = SerialObject.readNumber()	
      --next byte sent by microcontroller:
      MyVar2 = SerialObject.readNumber()	
      --third one sent by microcontroller:
      MyVar3 = SerialObject.readNumber()	
    end if
  end if  
end