LGDehome IIC/I2C/TWI LCD 1602 16x2 display issue

I am using the standard Hello World sketch to test the LGDehome.
I can turn the back light on and off. But the lcd.print(“Hello, world!”); function does not display anything.
I could use some help - thanks.


#include <LiquidCrystal_I2C.h>

// Set the LCD address to 0x27 for a 16 chars and 2 line display
LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup()
while (!Serial);
Serial.println("\nI2C Scanner");
// initialize the LCD`
// Turn on the blacklight and print a message.
lcd.print(“Hello, world!”);

void loop()
// Do nothing here…

Have you checked the I2C address is right? Have you adjusted the contrast potentiometer?

Like Buleste says, try the contrast first. You should get, at least, a row of blocks.

For an I2C LCD display to work, the I2C address and the I2C backpack to LCD pin mapping must be correct. If the library default settings for either or both are not correct the LCD will not work. You can try to figure out the right pin mapping and use an I2C scanner to find the address, but if you install and use the hd44780 library that is done automatically by the library.

Install the hd44780 library. The hd44780 library is the best available for I2C LCDs. The library is available in the Library Manager. Go to Library Manager (in the IDE, Sketch, Include Libraries, Manage Libraries) and in the Topics dropdown choose Display and in the Filter your search box enter hd44780. Select and install the hd44780 library by Bill Perry.

The class that you want to use is the hd44780_I2Cexp class. There are examples to show how to use the library. The nice thing about the hd44780 library is that it will autodetect the I2C address and the I2C backpack to LCD pin mapping.

In the examples, there is a diagnostic sketch that will help us to help you if you still have trouble with the display. Run the diagnostic sketch and post the results.