This is now the code on the motor controllers, that has the new current limiting, position reporting and position end limits, acceleration and variable braking.
You don't need to understand any of this code to use it. Just:
1. Connect the USB cable to a PC
2. Download the Arduino programmer:
https://www.arduino.cc/en/Main/Software
3. Copy and paste the code below into the programming tool
4. Set the device ID on the second line (any number from 0 to 255, used to identify the controller later) I'm using device IDs 10, 11 and 12 for this build.
5. Click the "Upload" button
Done!