public void calibrate()
  {
	  LCD.clearDisplay();
      System.out.println("Calibrate T2");
    
      for (byte i = 0; i < 3; i++)
      {
        while (0 == Button.readButtons())//wait for press
        {
          LCD.drawInt(leftEye.getLightValue(), 4, 6, 1 + i);
          LCD.drawInt(rightEye.getLightValue(), 4, 12, 1 + i);
          if (i == 0)
          {
            LCD.drawString("LOW", 0, 1 + i);
          } else if (i == 1)
          {
            LCD.drawString("HIGH", 0, 1 + i);
          } 
        }
        Sound.playTone(1000 + 200 * i, 100);
        if (i == 0)
        {
          leftEye.calibrateLow();
          rightEye.calibrateLow();
        } else if (i == 1)
        {
          rightEye.calibrateHigh();
          leftEye.calibrateHigh();
        } 
        while (0 < Button.readButtons())
        {
          Thread.yield();//button released
        }
       
    }
    while (0 == Button.readButtons())// while no press
    {
      int lval = leftEye.getLightValue();
      int rval = rightEye.getLightValue();
      LCD.drawInt(lval, 4, 0, 5);
      LCD.drawInt(rval, 4, 4, 5);
      LCD.drawInt(CLDistance(lval, rval), 4, 12, 5);
      LCD.refresh();
    }
    LCD.clear();
  }