HD44780-based LCD driver

This module provides a simple interface for controlling character LCDs based on the HD44780 driver. It supports displaying text, controlling the cursor position, and creating custom characters on the LCD screen.

Example

from machine import Pin
import time
from lcd_hd44780 import LcdHd44780

# Initialize the LCD with control pins (RS, E) and data pins (D4, D5, D6, D7)
lcd = LcdHd44780(rs=26, e=25, d=[13, 10, 9, 27])

# Move cursor to line 1, column 3 and display text
lcd.move_to(1, 3)
lcd.write("Hello, World!")

lcd.move_to(2, 5)
lcd.write("MicroPython")

Authors

Shujen Chen et al. Raspberry Pi Pico Interfacing and Programming with MicroPython
Tomas Fryza

Modification history

2024-11-11 : Added Sphinx-style comments for documentation.
2024-10-26 : Added demo method to demonstrate usage of the display.
2023-10-17 : File created, initial release.

class lcd_hd44780.LcdHd44780(rs, e, d)[source]

Bases: object

command(cmd)[source]

Send a command byte to the LCD controller. This method writes to the command register of the LCD (RS = 0).

Parameters:: cmd – The command byte to send to the LCD.

custom_char(addr, charmap)[source]

This method writes the pixel data for the custom character to one of the 8 available character generator RAM (CGRAM) locations.

Parameters:

addr – The address (0 to 7) in the CGRAM to store the custom character.
charmap – A list of 8 bytes representing the custom character’s pixel pattern.

Note

Inspired by peppe8o and MicrocontrollersLab.

data(val)[source]

Send a data byte to the LCD controller. This method writes to the data register of the LCD (RS = 1).

Parameters:: val – The data byte to send to the LCD.

move_to(line, column)[source]

Move the cursor to a specified position on the LCD. The method supports two lines.

Parameters:

line – The line number (1 or 2).
column – The column number (1 to 20).

write(s)[source]

Display a string of characters on the LCD. This method writes each character of the string to the LCD, one by one.

Parameters:: s – The string of characters to display on the LCD.

lcd_hd44780.demo()[source]: Demonstrates the usage of the LcdHd44780 class by initializing an LCD display, positioning text, and displaying a sample message.