Screens may come with different I2C addresses, trying these addresses should help : 0x27 or 0x3f If your display still does not work : Use testing mode in order to show "hello world" on the screen at ...

Components Needed:** Arduino board (e.g. Arduino Uno) Adafruit R307 fingerprint sensor 20x4 LCD I2C module 6 solenoid locks Jumper wires Fingerprint Sensor Connections: Connect the fingerprint ...

Hitachi’s HD44780 based 16×2 character LCD are very cheap and widely available, and is an essential part for any project that displays information. Using the LCD backpack, desired data can be ...

Step-by-step guide on designing and programming a custom I2C slave sensor device using Arduino.