title: More detail about new AVR instructions LAC, LAS, LAT and XCH
body: <p>Looking at the AVR instruction set there are four instructions added in 2010</p>
  
  <pre><code>LAC load and clear
  LAS load and set
  LAT load and toggle
  XCH load and exchange
  </code></pre>
  
  <ol>
  <li><p>Does anyone know what chips have these instructions</p></li>
  <li><p>What tools support these instructions</p></li>
  <li><p>More information on what they do  </p>
  
  <p>(Z) &lt;- Rd v (Z), Rd &lt;- (Z)</p></li>
  </ol>
  
  <p>does that imply that Rd and (Z) get the same value or does Rd get the pre-modified value of what was pointed to by Z?</p>