Arduino MicroPython LCD 20x4

This tutorial will instruct you how to use a 20x4 LCD I2C display with an Arduino board using MicroPython. You will learn:

Arduino MicroPython and LCD I2C 20x4

Hardware Preparation

1×Arduino Giga R1 WiFi
1×USB Cable Type-C
1×LCD 20x4
1×Jumper Wires
1×(Recommended) Screw Terminal Block Shield for Arduino Uno/Mega/Giga
1×(Recommended) Breadboard Shield For Arduino Uno/Mega/Giga
1×(Recommended) Enclosure For Arduino Giga

Or you can buy the following sensor kits:

1×DIYables Sensor Kit (30 sensors/displays)
1×DIYables Sensor Kit (18 sensors/displays)
Disclosure: Some of the links provided in this section are Amazon affiliate links. We may receive a commission for any purchases made through these links at no additional cost to you.
Additionally, some of these links are for products from our own brand, DIYables.

Overview of LCD I2C 20x4

Pinout

The LCD 20x4 I2C connects using the I2C interface and has 4 pins.

  • GND pin: Connect this to GND (0 volts).
  • VCC pin: Connect this to VCC (5 volts) to power the LCD.
  • SDA pin: Used for I2C data signal.
  • SCL pin: Used for I2C clock signal.
LCD 20x4 I2C Pinout

LCD Coordinate

The LCD I2C 20x4 includes 20 columns and 4 rows. Both columns and rows begin at 0.

Arduino MicroPython LCD I2C Coordinate

Wiring Diagram

The wiring diagram between Arduino MicroPython LCD 20x4 I2C

This image is created using Fritzing. Click to enlarge image

LCD I2C Arduino Giga
VCC Vin 5V
GND GND
SDA D9
SCL D8

Arduino MicroPython Code

The below MicroPython code displays string, integer and float number on LCD 20x4 display.

""" This Arduino MicroPython script was developed by newbiely.com This Arduino MicroPython script is made available for public use without any restriction For comprehensive instructions and wiring diagrams, please visit: https://newbiely.com/tutorials/arduino-micropython/arduino-micropython-lcd-20x4 """ from machine import I2C, Pin from DIYables_MicroPython_LCD_I2C import LCD_I2C import utime # The I2C address of your LCD (Update if different) I2C_ADDR = 0x27 # Use the address found using the I2C scanner # Define the number of rows and columns on your LCD LCD_COLS = 20 LCD_ROWS = 4 # Initialize I2C i2c = I2C(1) # Arduino Giga R1 WiFi I2C1 pins: SCL-D8, SDA-D9 # Initialize LCD lcd = LCD_I2C(i2c, I2C_ADDR, LCD_ROWS, LCD_COLS) # Setup function lcd.backlight_on() lcd.clear() # Main loop function while True: lcd.clear() lcd.set_cursor(0, 0); # Move cursor at the first row, first column lcd.print("LCD 20x4"); # Display text at the first row lcd.set_cursor(0, 1); # Move cursor at the second row, first column lcd.print("I2C Address: 0x27"); # Display text at the second row lcd.set_cursor(0, 2); # Move cursor at the third row, first column lcd.print("DIYables"); # Display text at the third row lcd.set_cursor(0, 3); # Move cursor at the fourth row, first column lcd.print("www.diyables.io"); # Display text at the fourth row utime.sleep(2) lcd.clear() lcd.set_cursor(0, 0) # Move to the beginning of the first row lcd.print("Int: ") lcd.print(str(197)) # Print integer lcd.set_cursor(0, 1) # Move to the beginning of the second row lcd.print("Float: ") lcd.print(str(26.39)) # Print float utime.sleep(2)

Detailed Instructions

Here’s instructions on how to run the above MicroPython code on Arduino with Thonny IDE:

  • Make sure Thonny IDE is installed on your computer.
  • Make sure MicroPython firmware is installed on your Arduino board.
  • If you are new to Arduino with MicroPython, see the Getting Started with Arduino and MicroPython.
  • Connect the LCD 20x4 display to the Arduino according to the provided diagram.
  • Connect the Arduino board to your computer with a USB cable.
  • Open Thonny IDE and go to Tools Options.
  • Under the Interpreter tab, select MicroPython (generic) from the dropdown menu.
  • Select the COM port corresponding to your Arduino board (e.g., COM33 on Windows or /dev/ttyACM0 on Linux).
  • Navigate to the Tools Manage packages on the Thonny IDE.
  • Search “DIYables-MicroPython-LCD-I2C”, then find the LCD I2C library created by DIYables.
  • Click on DIYables-MicroPython-LCD-I2C, then click Install button to install LCD I2C library.
Arduino MicroPython LCD I2C library
  • Copy the above provided code and paste it to the Thonny IDE's editor.
  • Save the script to your Arduino board by:
    • Click the Save button, or use Ctrl+S keys.
    • In the save dialog, you will see two sections: This computer and MicroPython device. Select MicroPython device
    • Save the file as main.py
  • Click the green Run button (or press F5) to run the script. The script will execute.
  • Check out the result on the LCD 20x4 display.
Arduino MicroPython 20x4 LCD

Arduino - 20x4 LCD - Custom Character

It is similar to LCD 16x2, you can refer to the custom character section on Arduino MicroPython LCD I2C tutorial, and then adapt it for LCD 20x4 display

※ OUR MESSAGES

  • As freelancers, We are AVAILABLE for HIRE. See how to outsource your project to us
  • Please feel free to share the link of this tutorial. However, Please do not use our content on any other websites. We invested a lot of effort and time to create the content, please respect our work!