title: PN532 not responding to my SPI-Command (returns 0xAA)
body: <p>I am trying to use a PN532(NFC controller). Lately something in my SPI-communication is off. I start comunication by asking for the firmewareversion (D4 02). Next I try to set the SAM-Config. But the PN532 wont give an ACK nor an response.</p>
  
  <p>What I observed is this. (all in hex)</p>
  
  <pre><code>GetFirmewareversion --- ACK&lt;br&gt;
  MOSI: 01 00 00 FF 02 FE D4 02 2A 00 --- 02 00 03 00 00 00 00 00 00&lt;br&gt;
  MISO: 00 FF FF FF FF FF FF FF FF FF --- FF 01 01 00 00 FF 00 FF 00
  
  Receive Firmewareversion after ACK&lt;br&gt;
  MOSI: 02 00 03 00 00 00 00 00 00 00 00 00 00 00 00&lt;br&gt;
  MISO: 00 01 01 00 FF 06 FA D5 03 32 01 06 07 E8 00
  
  Set SAMConfig --- see if ready(endless)&lt;br&gt;
  MOSI: 01 00 00 FF 05 FB D4 14 01 14 01 02 00 --- 02 00 --- 02 00 --- 02 00&lt;br&gt;
  MISO: AA AA AA AA AA AA AA AA AA FF FF FF FF --- FF 00 --- 00 00 --- 00 00
  </code></pre>
  
  <p>When I write my getFiremware he responds 0xFF, but when i try to set SAM he always responds with 0xAA. He also never replies an ACK or response to setSAMConfig.</p>
  
  <p>Where is my Mistake? where is this Coming from? How to fix it?
  THX in advance.</p>