This tutorial demonstrates how to use our FC-113 IIC/I2C Serial Interface Adapter Module For 1602 LCD Display. These serial interface modules simplifies connecting an Arduino to a 1602 Liquid Crystal display using only 4 wires. This module uses the PCF8574T IC chip.
What you’ll need:
- An Arduino – (We’re using an Arduino Uno for this demonstration.)
- 4 Male-to-Female Jumper Wires
- An IIC/I2C Serial Interface Module
- A 1602 Display
- 40-pin Male header pins (optional, for breadboard use)
- 400-point half-size breadboard (optional, for temporary setup)
- LiquidCrystal Library from fmalpartida (I’m using v 1.2.1)
You’ll have to remove the LiquidCrystal library that is included with Arduino. It should be in your Arduino install folder, ie. C:\Program Files(x86)\Arduino\libraries\ . I recommend creating a new zip file of the existing LiquidCrystal library, then delete the LiquidCrystal library. You can then copy the newly downloaded LiquidCrystal library to this directory. If you already have the Arduino software open, close it and re-launch it so the changes will be loaded.
Connect the I2C Module to 1602 Display
There’s essentially two ways to connect these:
- Solder header pins to your 1602 display and use a breadboard (as I’ve shown in the first photo). Make sure you connect the pins correctly.
- Solder the I2C module directly to the 1602 display. As before, make SURE you connect the pins on the module to the correct connections on the display. It’s quite simple and goes only one way, but I suppose one *could* still solder it backwards even though it looks completely wrong.
Connect the I2C Module to the Arduino
This is really simple and here are the connections:
SCL = A5
SDA = A4
VCC = 5V+
GND = GND
Load the Arduino Sketch
I’ve created a simple sketch to get you started. You can copy the code from this github gist:
It should work just fine once you upload it to your Arduino. If the display doesn’t look quite right, adjust the trimmer potentiometer (blue square thingy on the module) to correct the contrast. One neat feature with this module is you can turn the backlight off, such as after a certain amount of time, etc. I’ve noted how to do this in the code, but the rest is up to you.