title: Python hex bit flipping ascii
body: <p>The following statement is from a documentation I'm following.</p>
  
  <pre><code>“7c bd 9c 91” 2442968444(919cbd7c hex)usec = 2442.9sec
  </code></pre>
  
  <p>If you assume:</p>
  
  <ol>
  <li>7c -> a</li>
  <li>bd -> b</li>
  <li>9c -> c</li>
  <li>91 -> d</li>
  </ol>
  
  <p>Then its easy to see how they got <code>919cbd7c</code> simply by flipping it <code>abcd</code> to <code>dcba</code>. </p>
  
  <p>What I don't understand is why they aren't filliping the actual bits. </p>
  
  <p>That is to say I expect <code>19c9dbc7</code> rather than <code>919cbd7c</code>.</p>
  
  <p>Is there a way to convert the original string to what they expect?</p>
  
  <p>EG: convert <code>7cbd9c91</code> to <code>919cbd7c</code>?</p>
  
  <p>I know that I can split the string in twos and reverse the order. But is there a way python is aware of this and can decode it automatically?</p>
  
  <p>Here is the <a href="http://velodynelidar.com/docs/manuals/63-9113%20HDL-32E%20manual_Rev%20H_Sept.pdf" rel="nofollow">documentation</a>. The part in question is on the 2nd line of page 22. </p>