s onto a single carrying medium. For example 
      a thousand telephone calls can be carried on a single cable. De-multiplexing 
      separates the channels and routes them to their correct destinations.</td>
  </tr>
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    <td><strong>NULL </strong></td>
    <td>ASCII code zero used to mark the end of text strings.</td>
  </tr>
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    <td><strong>O Flag </strong></td>
    <td>The O or overflow Flag in the status register indicates if the previous 
      calc