Some usefull info for this files/codes
Code editor / compiler
https://www.arduino.cc/en/software (2.0.3)
Code dependencies:
https://github.com/earlephilhower/arduino-pico
https://github.com/adafruit/Adafruit_NeoPixel
https://github.com/khoih-prog/RP2040_PWM
https://github.com/olikraus/u8glib
Simulation program:
https://www.analog.com/en/design-center/design-tools-and-calculators/ltspice-simulator.html
The schematics were built with EasyEDA