title: Node Red. Extracting bytes from a buffer
body: <p>I have a collection of sensors using LoRaWan to connect via ttn to a Node Red application and this is working very well.</p>
  
  <p>For bandwidth economy I want to try not using my present payload configuration and just transmit an array of 8 bytes.</p>
  
  <p>If I do this the output from the ttn uplink node is <code>msg.payload:buffer[8]</code> followed by e.g. <code>[10, 175, 0, 232, 0, 4, 9, 1]</code>.</p>
  
  <p>In Node Red how do I extract the individual bytes from the array?</p>