README.md

PCF8574 STM32 HAL Library

This library allows you to control the PCF8574 I/O expander using the STM32 HAL library. It supports setting and reading individual pins and controlling multiple PCF8574 modules on a single I2C bus.

Features

• Control individual pins on the PCF8574.
• Support for multiple PCF8574 modules on the same I2C bus.
• Easily toggle, set, or read the state of each pin.
• Compatible with STM32 HAL library.

Requirements

• STM32 microcontroller
• STM32 HAL library
• I2C communication bus

Getting Started

Hardware Setup

Connect the PCF8574 to the I2C bus of the STM32 microcontroller. You can connect up to 8 PCF8574 modules on the same bus by configuring the A0, A1, and A2 address pins.

Software Setup

1. Include the pcf8574.h and pcf8574.c files in your project.
2. Make sure that the I2C peripheral is initialized in your STM32 project.

Example Usage

Here is an example of how to initialize and use the library:

#include "pcf8574.h"

// Create a handle for PCF8574
PCF8574_HandleTypeDef pcf8574;

int main(void) {
    // HAL initialization
    HAL_Init();
    
    // I2C handle (example, customize as needed)
    I2C_HandleTypeDef hi2c1;
    // Initialize your I2C peripheral (ensure this is done based on your project setup)
    // HAL_I2C_Init(&hi2c1);

    // Initialize the PCF8574 with the desired address (A0 = 0, A1 = 0, A2 = 0)
    PCF8574_Init(&pcf8574, &hi2c1, 0, 0, 0);

    // Set Pin 0 to HIGH (1)
    PCF8574_WritePin(&pcf8574, 0, GPIO_PIN_SET);

    // Read the state of Pin 0
    GPIO_PinState state = PCF8574_ReadPin(&pcf8574, 0);

    while (1) {
        // Toggle Pin 0
        PCF8574_TogglePin(&pcf8574, 0);

        // Delay for 500 ms
        HAL_Delay(500);
    }
}