Arduino - Two wire I2C Lcd Display

Hello Guys!

This is the first tutorial I’m posting on Steemit, and by this, I want to present you a very simple project, explaining how you can wire up your Arduino to your Lcd with just 2 wires.

As you can see in the image above, we are only wiring Analog Pin 4 and 5 to our breadboard. This can be possible with the aid of that black chip named PCF8574.

This chip is a 8-bit input/output (I/O) expander, designed for 2.5-V to 6-V VCC operation. The PCF8574 provides general-purpose remote I/O expansion for most microcontroller families by way of the I2C interface [serial clock (SCL), serial data (SDA)].

This means that with with this chip, from two analog pins and using a proper library, you can expand your arduino to have more 8 digital pins.

Bellow are the materials that you need to have to build this:

• Arduino Uno
• PCF8574
• 100K Ohm Potenciometer
• Lcd 16×2
• Male Headers
• Breadboard and Wires

After you gathered all the materials need to do this project, it’s time to print some text to our lcd.

First wire everything as shown in the diagram above.

Then you will need to install the library liquidcrystal_i2c in your arduino IDE. You can find the instructions to installing it following the link.

To end our project just upload this piece of code to your arduino:

#include 
#include 
LiquidCrystal_I2C lcd(0x20,16,2);
void setup()
{
    lcd.init();
    lcd.setCursor(0,0);
    lcd.print("Hello, world!");
}
void loop()
{
  lcd.setCursor(0,1);
  lcd.print(millis()/1000);
}

Hopefully it will work 😀

Please let me know if you have any questions or doubts!