title_body: How to drive a servo for a tricopter with a flight controller?
upvoted_answer: This has likely been answered here: https://drones.stackexchange.com/a/230/50, but to paraphrase:
  
  A standard flight controller can easily be set up to control a servo, as per your edit.
  
  You first need to plug in your flight controller (with props off, if you’re using one with motors already attached) and enable ’servo tilt’ in the configuration tab, then go into the CLI.
  
  You then need to type ‘resource’ (assuming you are on the latest version of Betaflight.)
  
  As you want a tricopter and your flight controller is likely for a quadcopter at least, you can reassign a motor output (or any other PDB with a built-in timed) to become a servo output. If you don’t know how to re-map resources in Betaflight, the answer I have linked gives an excellent rundown.
  
  You should then see a servo tab appear in Betaflight, and from there you should be able to configure everything you need.