GPIO Utilities for STM32

This project provides simple GPIO utility functions and structures for STM32 microcontrollers, for polling-driven button and pin handling. It is written in C, works with C++ projects, uses the STM32 HAL library, and has been tested on the STM32F303RET6.

Features

• Simple abstractions for GPIO pins and buttons
• Inline functions
• Button press handling using polling with callback support

Usage

pin.h

Defining a pin:

const pin_t LD2 = {LD2_GPIO_Port, LD2_Pin};

Writing to a pin:

write_pin(&LD2, GPIO_PIN_SET);

write_pin(&LD2, GPIO_PIN_RESET);

Toggling a pin:

toggle_pin(&LD2);

Reading from a pin:

GPIO_PinState state = read_pin(&LD2);

if (state == GPIO_PIN_SET)
{
    // do stuff...
}

btn.h

Defining a button:

btn_t user_btn = {
		{USER_BTN_GPIO_Port, USER_BTN_Pin},
		false
};

Defining a callback function:

void handle_user_btn(void *ctx)
{
	// do stuff...
}

Then, in the main event loop:

handle_btn_press(&user_btn, handle_user_btn, NULL); // for callbacks without arguments

You can pass arguments to the callback function using the void *ctx parameter:

void increment_counter(void *ctx)
{
	int *counter = (int *)ctx;
    ++(*counter);
}

// ...

int counter = 0;

while (1)
{
    handle_btn_press(&user_btn, increment_counter, &counter);
    // ...
}