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Topic: LCD I2C does not work (Read 262 times) previous topic - next topic

Sheiky

Hello,
I connected this LCD with SCL,SDA,VSS,GND
https://www.ebay.de/itm/201399759420

to this Arduino R3
https://www.diymore.cc/products/atmega328p-ch340g-uno-r3-board-mini-usb-compatible-with-arduino-uno-r3
at SCL,SDA,5V,GND

and used this library
https://github.com/fdebrabander/Arduino-LiquidCrystal-I2C-library
with the example there:
Code: [Select]
#include <Wire.h>
#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()
{
 // initialize the LCD
 lcd.begin();

 // Turn on the blacklight and print a message.
 lcd.backlight();
 lcd.print("Hello, world!");
}

void loop()
{
 // Do nothing here...
}

without success.
Thank you for any help available.


Erik_Baas

Does the backlight work? If so, try rotating the trimpot on the I2C interface clockwise to increase the contrast of the display.

Sheiky

Hello,
yes, backlight works, if i shortcut the 2 pins at LED

But I guessed the problem is the upload.
I changed the old IDE 1.6.9 to new 1.8.21.0 win10 app.
Before I selected the board Duemilanove without any errors.
Now selecting this board gives upload error.

Thank you

bperrybap

Use the hd44780 library. It is in the library manager.
Use the hd44780_I2Cexp i/o class.
First run I2CexpDiag sketch to test i2c signals, backpack and lcd.
Documentation is available in the library and on the github page: https://github.com/duinoWitchery/hd44780

--- bill

Sheiky

Tried sometimes changing ports and boards and uploaded again properly.
LED blinking red and green sometimes, but still thinking LCD still not working.

Turned the poti and all is good.
Great, thank you very much

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