Exercise 1: Make a Processing Etch A Sketch
Arduino to Processing! I used two potentiometers to control the location of the dot/line. One is for X and the other is for Y. The line is more difficult than eclipse since the location depends on the distance of two dots.
Exercise 2: Make a musical instrument with Arduino
Processing to Arduino! In Arduino, I used the tone function( tone (pin mode, frequency, duration）），and in Processing, I divided the canvas into 4 parts, X>250,Y>250;X<250,Y>250;X>250,Y<250;X<250,Y<250; each part has a different tone. Then pass it to the Arduino.