title: Do interrupts interrupt other interrupts on Arduino?
body: <p>I have an <a href="http://arduino.cc/en/Main/ArduinoBoardUno" rel="noreferrer">Arduino Uno</a> (awesome little device!). It has two interrupts; let's call them <strong>0</strong> and <strong>1</strong>. I attach a handler to interrupt 0 and a different one to interrupt 1, using <code>attachInterrupt()</code> : <a href="http://www.arduino.cc/en/Reference/AttachInterrupt" rel="noreferrer">http://www.arduino.cc/en/Reference/AttachInterrupt</a>.</p>
  
  <p>Interrupt <strong>0</strong> is triggered and it calls its handler, which does some number crunching. If interrupt <strong>0</strong>'s handler is still executing when interrupt <strong>1</strong> is triggered, what will happen?</p>
  
  <p>Will interrupt <strong>1</strong> interrupt interrupt <strong>0</strong>, or will interrupt <strong>1</strong> wait until interrupt <strong>0</strong>'s handler is done executing? </p>
  
  <p>Please note that this question specifically relates to Arduino.</p>