Getting Started with STM32

What is STM32 / When to Use It

STM32 is a family of 32-bit ARM Cortex-M microcontrollers by STMicroelectronics. Use STM32 for real-time control, precise timing, CAN bus, industrial communication, or DSP.

Which STM32?

Series	Core	Speed	Flash	Best For
STM32F103 Blue Pill	Cortex-M3	72 MHz	64 KB	Budget learning, basic control
STM32F407 Black	Cortex-M4F	168 MHz	512 KB	DSP, motor control, audio
STM32G0	Cortex-M0+	64 MHz	32 KB	Low power, cost-sensitive
STM32H743	Cortex-M7	480 MHz	1 MB	High-speed DSP, AI inference
STM32WL	Cortex-M4 + LoRa	48 MHz	256 KB	LoRaWAN end-devices

Prerequisites

• STM32 dev board (Nucleo, Discovery, or Blue/Black Pill)
• ST-Link v2 programmer (Nucleo/Discovery have built-in)
• USB cable

Install Toolchain

STM32CubeIDE (Recommended)

1. Download from st.com (free, needs ST account)
2. Install and launch
3. Create new project: File → New → STM32 Project
4. Select your MCU (e.g., STM32F407VGT6)
5. Configure pins in the .ioc file (graphical pinout editor)
6. Generate code — CubeMX creates HAL init code automatically

PlatformIO (VSCode)

platformio init --board black_f407ve

Framework: stm32cube (HAL) or libopencm3 (lightweight).

ARM GCC + Make (Advanced)

sudo apt install gcc-arm-none-eabi openocd

First Example: Blink with HAL

#include "main.h"
void SystemClock_Config(void);
static void MX_GPIO_Init(void);

int main(void) {
  HAL_Init();
  SystemClock_Config();
  MX_GPIO_Init();
  while (1) {
    HAL_GPIO_TogglePin(GPIOD, GPIO_PIN_12);
    HAL_Delay(500);
  }
}

Common Issues

Problem	Fix
ST-Link not detected	Install ST-Link driver from st.com
No serial output	Enable UART in CubeMX pinout config
Wrong chip detected	Check SWD wiring — SWCLK/SWDIO not swapped
Code too large	Blue Pill only 64 KB; upgrade to F4
CubeIDE slow	Use PlatformIO instead

Flashing via UART (no ST-Link)

1. Set BOOT0 pin HIGH, BOOT1 LOW
2. Connect USB-UART to PA9 (TX) and PA10 (RX)
3. Use stm32flash: stm32flash -w firmware.bin -v /dev/ttyUSB0

Questions about this guide?

Ask on the Community Forum — share your project, get help, or help others.

Next Steps

• What is I2C
• Dev Board Selection