Embedded Peripheral Drivers for STM32F4xx

Overview

This project provides bare-metal peripheral drivers for STM32F4xx microcontrollers, implemented from scratch without using HAL or CMSIS. The goal is to develop a deeper understanding of low-level embedded programming by directly interacting with hardware registers. This project includes both polling-based and interrupt-based implementations for all peripheral drivers, ensuring efficient and responsive communication. Future plans include implementing DMA-based data transfer for enhanced performance.

Features

✔️ GPIO (General Purpose Input/Output) Driver with Polling and Interrupt Support
✔️ I2C (Inter-Integrated Circuit) Driver with Polling and Interrupt Support
✔️ SPI (Serial Peripheral Interface) Driver with Polling and Interrupt Support
✔️ Bare-metal register-level programming (No HAL, No CMSIS)
✔️ Structured, modular, and reusable driver architecture
✔️ Upcoming: DMA-based data transfer for optimized performance

Project Structure

EmbeddedPeripheralDrivers_STM32/
│
├── Src/                # Source files
│   ├── main.c          # Application code
│   ├── gpio_driver.c   # GPIO driver implementation
│   ├── i2c_driver.c    # I2C driver implementation
│   ├── spi_driver.c    # SPI driver implementation
│
├── Inc/                # Header files
│   ├── gpio_driver.h
│   ├── i2c_driver.h
│   ├── spi_driver.h
│
├── Startup/            # Startup assembly file
│   └── startup_stm32f407xx.s
│
├── Linker/             # Linker scripts
│   ├── STM32F407VGTX_FLASH.ld
│   ├── STM32F407VGTX_RAM.ld
│
├── .gitignore
├── README.md           # Project documentation
└── LICENSE             # Project license

---

Getting Started

Prerequisites

• ✅ Hardware: STM32F4 Discovery Board or equivalent
• ✅ Toolchain: ARM GCC Compiler, STM32CubeIDE, or Keil uVision
• ✅ Debugger: ST-Link V2 / Onboard Debugger

Setup & Compilation

1. Clone the Repository

   git clone https://github.com/bobburudinesh/EmbeddedPeripheralDrivers_STM32.git

2. Open the project in STM32CubeIDE / Keil / Any ARM Compiler
3. Build the project
4. Flash the binary to STM32F4 using ST-Link
5. Verify the peripheral functionality

---

Peripheral Driver Implementations

1. GPIO Driver

• Configures pin modes, speed, and pull-up/pull-down resistors.
• Example usage:

  GPIO_InitTypeDef gpio;
  gpio.pin = GPIO_PIN_13;
  gpio.mode = GPIO_MODE_OUTPUT;
  gpio.speed = GPIO_SPEED_LOW;
  GPIO_Init(GPIOC, &gpio);
  GPIO_TogglePin(GPIOC, GPIO_PIN_13);

2. I2C Driver

• Implements I2C communication using register-level programming.
• Example usage:

  uint8_t data = 0xAA;
  I2C_MasterTransmit(&i2c, EEPROM_ADDRESS, &data, 1);

3. SPI Driver

• Supports master/slave communication, full-duplex data transmission.
• Example usage:

  uint8_t tx_data = 0x55, rx_data;
  SPI_Transmit(&spi, &tx_data, 1);
  SPI_Receive(&spi, &rx_data, 1);

---

Example Application

This project includes a basic GPIO LED blink example using the custom GPIO driver.

#include "gpio_driver.h"

int main(void) {
    GPIO_InitTypeDef gpio;
    gpio.pin = GPIO_PIN_13;
    gpio.mode = GPIO_MODE_OUTPUT;
    GPIO_Init(GPIOC, &gpio);

    while (1) {
        GPIO_TogglePin(GPIOC, GPIO_PIN_13);
        for (volatile int i = 0; i < 100000; i++); // Delay
    }
}

---

Future Enhancements

🚀 Adding DMA-based peripheral communication for optimized performance
🚀 Adding UART Driver
🚀 Adding PWM Driver

Contributing

Contributions are welcome! To contribute:

1. Fork the repository
2. Create a new feature branch
3. Commit and push your changes
4. Open a pull request

---

License

This project is licensed under the MIT License – see the LICENSE file for details.