title: PHP - convert little endian hex to big endian hex
body: <p>I am trying to convert <strong>little endian</strong> hex to <strong>big endian</strong> hex.</p>
  
  <p>Example:</p>
  
  <p>Little endian: 
  <code>E1 31 01 00 00 9D</code></p>
  
  <p>Big endian:
  <code>9D 00 00 01 31 E1</code></p>