title: Arduino Due LED control LED remains on
body: <p>I'm using an <a href="http://arduino.cc/en/Main/ArduinoBoardDue" rel="nofollow">Arduino Due</a>, and 4x <a href="http://www.maximintegrated.com/datasheet/index.mvp/id/1339" rel="nofollow">MAX7219</a> ICs to control a 16x16 matrix of <a href="http://en.wikipedia.org/wiki/Light-emitting_diode" rel="nofollow">LEDs</a>. It works great, but there is just one LED that remains on (on row 0 col 15), even if I clear my display, or even manually turn it off.</p>
  
  <p>I use the LED control library <a href="http://playground.arduino.cc/Main/LedControl" rel="nofollow">found on the Arduino playground</a>.</p>
  
  <p>How do I turn that one off?</p>