RPi_GPIO_i2c_LCD

HD44780 / PCF8574 LCD Module

View on PyPi.org

Sections

• Description
• Features
• Install
• Usage

Description

A simple module for working with the HD44780 LCD over I²C using the PCF8574 Backpack

Features

• Non-Blocking update loop
• Supports 2x16 and 4x20 Displays
• Easy to use
• Callback loop for updating display directly

Install

Make sure i2c is enabled! sudo raspi-config

Using PyPi:

pip3 install RPi-GPIO-I2C-LCD

Usage

set(string,line)

Sets string to given line

get(line)

Returns string of given line from buffer

backlight(on|off)

Turns backlight on or off (default is on)

clear()

Clears display buffers

Examples

Simple

from RPi_GPIO_i2c_LCD import lcd
from time import sleep
## Address of backpack
i2c_address = 0x27
## Initalize display
lcdDisplay = lcd.HD44780(i2c_address)
## Set string value to buffer
lcdDisplay.set("Hello",1)
lcdDisplay.set("World",2)
sleep(1)

Callback Loop

from RPi_GPIO_i2c_LCD import lcd
from time import sleep, strftime
## Callback function that will run on every display loop
def MyFunction(self):
    ## Show current time on line 2
    self.lcd.display_string(str(strftime("%d/%m %H:%M:%S").center(20,' ')),2)
## Initalize display with callback
lcdDisplay = lcd.HD44780(0x27,MyFunction)
## Set string value to buffer
lcdDisplay.set("The time is:",1)
sleep(6)

Backlight

from RPi_GPIO_i2c_LCD import lcd
from time import sleep
## Address of backpack
i2c_address = 0x27
## Initalize display
lcdDisplay = lcd.HD44780(i2c_address)
## Set string value to buffer
lcdDisplay.set("Hello",1)
lcdDisplay.set("World",2)
while(True):
    lcdDisplay.backlight("off")
    sleep(1)
    lcdDisplay.backlight("on")
    sleep(1)