ock means that the CPU 
      performs 33 million steps per second. These sorts of speeds are needed to 
      fill screens with high resolution graphics quickly.</td>
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    <td><strong>Memory Mapped </strong></td>
    <td>Memory mapped hardware is controlled by writing data into memory locations 
      occupied by that hardware device. This simulator has a memory mapped screen 
      so each screen position corresponds to a memory location.</td>
  </tr>
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