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 ...

This project implements a scrolling marquee on a 20x4 I2C LCD display using an Arduino. The code displays static and scrolling text on different rows of the LCD, with adjustable scrolling speed.

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