title: Maximum packet length for Bluetooth LE?
body: <p>I was wondering what was the maximum packet length in Bluetooth Low Energy. The 20 bytes limit if often said, for <a href="https://stackoverflow.com/a/24178409/6708157">example here</a></p>
  
  <blockquote>
    <p>"BLE allow you transfer maximum is 20 bytes."</p>
    
    <p>"You are correct that the BLE specification doesn't allow write operations to exceed 20 bytes."</p>
  </blockquote>
  
  <p>However, reading the Bluetooth Core Specification, we can see that the ATT_MTU value is written with 2 bytes, meaning that it can go up to 65 535 bytes.</p>
  
  <p>What's the truth behind all this ?</p>