Arduino Mega rev3 - marcelarosalesj/arm GitHub Wiki
This is a pinout board, very useful since my arduino has a case and I cannot see the pins:
https://pandaelectronicsbd.com/wp-content/uploads/2017/05/Arduino-Mega-2560-Pinout-600x600.jpg
ATmega2560 pin mapping
https://www.arduino.cc/en/Hacking/PinMapping2560
Reading a potentiometer:
https://www.arduino.cc/en/tutorial/potentiometer
https://www.arduino.cc/en/Tutorial/AnalogReadSerial
Servos:
https://www.arduino.cc/en/Tutorial/Sweep
https://www.arduino.cc/en/Tutorial/Knob
video potentiometers moving arm
https://www.youtube.com/watch?v=gPu47Z3j4UM