# Password Lock System

Day 21 of the 100 Days 100 IoT Projects collection. Board: ESP32.

Enter a code on a keypad to unlock — the ESP32 checks it and lights up an LCD and LEDs. Keypad scanning and access logic from scratch.

## How it works

The keypad is scanned row by row to detect which key is pressed, building up the entered code character by character. The ESP32 compares it against the stored code; a match triggers the unlock feedback on the LCD and LEDs, a mismatch shows an error. The whole flow is a small access-control state machine.

## What you'll learn

- Matrix keypad scanning
- Code comparison logic
- Access state machines
- User feedback design

Full project (code, wiring diagram, Wokwi simulation): https://github.com/kritishmohapatra/100_Days_100_IoT_Projects/tree/main/Password_Lock_System_using_ESP32

Summary by SkillShop. Code and diagrams belong to the original repo.