This software runs on the Arduino UNO and is for the Squid Games doll to play red-light-green-light. All I/O are used in this project. The pinout is attached as a Fritzing diagram.
Please watch the YouTube video on this build: https://youtu.be/jd_4a4x3uCw
ELEGOO UNO R3 kit: (the kit used in this build) https://amzn.to/3Epuq6R
ELEGOO Mega R3 kit (optional kit) https://amzn.to/3Ex5dr0
DFPlayer Mini (simple MP3 player) https://www.dfrobot.com/product-1121.html?tracking=60d2f3a09e1f2