I cant get my new 16*2 I2C LCD work on MKR1310

Other Hardware Displays
1

Hi

Is there someone who managed to get a 16*2 I2C LCD display to work on a MKR1300 ?

I find the I2C adress but nothing show up on the display when I run this simple program. Pin 11 and 12 is used SDA/SLC

/* I2C LCD with Arduino example code. More info: https://www.makerguides.com */
// Include the libraries:
// LiquidCrystal_I2C.h: GitHub - johnrickman/LiquidCrystal_I2C: LiquidCrystal Arduino library for the DFRobot I2C LCD displays
#include <Wire.h> // Library for I2C communication
#include <LiquidCrystal_I2C.h> // Library for LCD
// Wiring: SDA pin is connected to A4 and SCL pin to A5.
// Connect to LCD via I2C, default address 0x27 (A0-A2 not jumpered)

LiquidCrystal_I2C lcd = LiquidCrystal_I2C(0x27, 16, 2); // Change to (0x27,16,2) for 16x2 LCD.
void setup() {
// Initiate the LCD:
lcd.init();
lcd.backlight();
}
void loop() {
// Print 'Hello World!' on the first line of the LCD:
lcd.setCursor(0, 0); // Set the cursor on the first column and first row.
lcd.print("Hello World!"); // Print the string "Hello World!"

}

2

I would recommend using the hd44780 library instead.
It comes with the hd44780_I2Cexp i/o class which supports using PCF8574 based backpacks.
It will auto detect the i2c address and the pin mapping used on the backpack. (not all i2c lcd backpacks use the same pin mapping)
It is available in the IDE library manager so you can install it directly from the IDE without having download anything like a zip file.
Once installed, you can access the hd44780 library documentation from the "Documentation" sketch example.
The i/o class you want to use is hd44780_I2Cexp.
First run the included diagnostic sketch I2CexpDiag to verify that everything is working.
Then you look at the included hd44780_I2Cexp i/o class examples.

You can also read about it on the github page: I would recommend using the hd44780 library instead.
It comes with the hd44780_I2Cexp i/o class which supports using PCF8574 based backpacks.
It will auto detect the i2c address and the pin mapping used on the backpack. (not all backpacks use the same pin mapping)
It is available in the IDE library manager so you can install it directly from the IDE without having download anything like a zip file.
Once installed, you can access the hd44780 library documentation from the "Documentation" sketch example.
The i/o class you want to use is hd44780_I2Cexp.
First run the included diagnostic sketch I2CexpDiag to verify that everything is working.
Then you look at the included hd44780_I2Cexp i/o class examples.

You can also read about it on the github page: GitHub - duinoWitchery/hd44780: Extensible hd44780 LCD library

--- bill

3

Also, that MKR1310 appears to be a 3.3 volt volt device.
If your LCD 1602 doesn't match this voltage, it could explain the problem.
Does the LCD 1602 have an unpopulated 8 pin chip footprint ? If so, it is a 5 volt device.
If you mix voltages, i.e. run the display at 5 volts, you should use level shifters on SDA/SCL.