Servo SBUS/PPM to Dynamixel

Robotis Dynamixel make some fantastic Servos.  Some of them can be controlled through a Radio Control receiver using PPM - but not all, and not the ones I wanted to use (XM540-W270-T) which can generate an incredible 10Nm torque.

I developed the first version as a simple PPM to Dynamixel converter, then thought, since multiple Dynamixels can be daisy-chained together - and most RC sets can use SBUS which allows a single reciever output to control multiple servos, it makes sense to use SBUS to control multiple Dynamixels.

I've implemented adjustable smoothing (via the variable resistor on board) which uses Kalman filters to remove judder & jerky movement from the servos.

The board has 4 settings switches with the following functions:

1 - Single Turn / Multi-Turn (10 turn)

2 - 50% / 100% Velocity

3 - Position / Velocity Mode (if you want to drive a wheel for example)

4 - PPM / SBUS

You need to cycle the power if you change a setting.

The Microcontroller (XAIO SAMD21) is powered either from USB or via the RC Receiver.  DO NOT CONNECT BOTH!  The receiver power will flow back through the USB port and (probably) damage your PC. (how do I know this!)

The example code is in my Github repo: https://github.com/SimonRafferty/Servo-SBUS-to-Dynamixel