[Sam Horne] adapted an old school landline phone to deliver clues to birthday party guests. When guests find a numerical clue, they type it into the keypad to hear the next clue, which involves ...

If you want to add a keypad to your Arduino project, the options are pretty limited. There’s that red and blue 4×4 membrane we’ve all seen in password-protected door lock projects, and the phone ...

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Contents presented in the Microcontrollers Laboratory Course; Microcontrollers used: Arduino UNO R3 & DOIT ESP32 DEVKIT V1 - CSE Department, Shiraz University, Spring 2025.