LCD I2c is not showing any word

Other Hardware Displays
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#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);
const byte led = 14;
void setup() {
  // put your setup code here, to run once:
  lcd.init();
  lcd.clear();
  lcd.backlight();
  pinMode(led, OUTPUT);
  Serial.begin(9600);
  lcd.setCursor(0, 0);
  lcd.print("Hello world!");
  delay(1000);

}

void loop() {
  // put your main code here, to run repeatedly:

  //digitalWrite(led, HIGH);
  //delay (700);
 // digitalWrite(led, LOW);
 // delay (700);
}

Hi all, I have a problem on lcd which it can work but the words is not display to the screen of lcd. I tried already on the arduino and esp32 , both not working. Can anyone help me?

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Your topic was MOVED to its current forum category which is more appropriate than the original as it has nothing to do with Installation and Troubleshooting of the IDE

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  • What do you see on the display?
  • Show a picture of your Arduino + LCD so we can see the Wiring.
  • Check with the I2C-Scanner if your PCF8574 ist really on 0x27 and not for example on 0x3F.
    You find the I2C-Scanner in the wire examples.
  • Post the result of the I2C-Scanner.
4

Check the bad Lcd soldering, which is the most common reason the LCD not displaying any text. If your LCD worked earlier, then that is a software bug.

5

Have you tried the contrast adjustment?

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.

To 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 menus, 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.

And I agree with @noiasca, clear photos of the connections between the LCD and Arduino and the connections between the LCD and I2C backpack are often very useful.

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well the address might be wrong.... is that sketch exactly the example that comes with the library ? you should get at least 1 example to run...

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