title_body: How to connect ESC to serial?
upvoted_answer: Thanks to informations given by @ifconfig, using BLHeliSuite connecting :
  
  GND to Arduino GND
  ESC1 to Arduino D11
  
  It allow to upload to Arduino the &quot;Arduino Bootloader&quot;
  
  Then selecting &quot;ATMEL BLHeli Bootloader (USB/Com)&quot;, and go to &quot;ESC Setup&quot; tab
  
  Finally quite straight-forward, with a tool that may be more user-friendly.