The I2c protocole is commonly used for establishing communication between master and
slaves at low speed.
The hd44780 is a widespread common LCD controller allowing to drive various formats
of LCD displays made of 1 line with 8 characters (1X8), 2X16, 2X20, 4x20 or others.
It can be driven through a pcf8574 device which provides general-purpose remote
I/O expansion by way of the I2C interface [serial clock (SCL), serial data (SDA)].
This example was developed using the System Workbench for STM32 programing environment (sw4stm32 eclipse)
The following equipment is used
- NUCLEO-L476RG Board or equivalent and a HD44780 LCD with a PCF8574 expander
like Quimat IIC/I2C/TWI Serial 2004 20x4 LCD Module
- Eclipse with the necessary packages for Nucleo boards installed
- OpenOCD or STLink USB Driver - STM32CubeMX
The goal of this tutorial is aimed at showing to hobbyists and students how to develop and to use a small I2C library for LCD displays.
full professor @ phelma Grenoble Institute of Technology