STM32 Flight Controller Unit


The STEVAL-FCU001V1 is a Cortex M4 MCU-based flight controller unit for toy quad-copter drones.

STM32 Flight Controller Unit


STM32 Flight Controller Unit provides the following hardware components:

  • STM32F401CC in UFQFPN48 package
  • ARM® 32-bit Cortex®-M4 MCU with FPU
  • 84MHz max MCU frequency
  • VDD from 1.7 V to 3.6 V
  • 256 KB FLASH
  • 64 KB SRAM
  • General Purpose Timers
  • Watchdog Timers (2)
  • On board sensors:
    • 3D Accelerometer and 3D Gyroscope: LSM6DSL
    • 3D Magnetometer: LIS2MDL
    • MEMS Pressure sensor: LPS22HD
  • 2 User LEDS
  • USART/UART (1)
  • I2C (1)
  • Bluetooth LE over SPI

More information about the STM32 Flight Controller Unit can be found in these documents:

Supported Features

The Zephyr steval_fcu001v1 board configuration supports the following hardware features:

Interface Controller Driver/Component
NVIC on-chip nested vector interrupt controller
UART on-chip serial port-polling; serial port-interrupt
PINMUX on-chip pinmux
GPIO on-chip gpio
PWM on-chip pwm
I2C on-chip i2c

The default configuration can be found in the defconfig file: boards/arm/steval_fcu001v1/steval_fcu001v1_defconfig

Default Zephyr Peripheral Mapping:

  • UART_1 TX/RX : PA9/PA10
  • I2C2 SCL/SDA : PB10/PB3
  • PWM_2_CH1 : PA0
  • LD1 : PB5
  • LD2 : PB4

System Clock

The steval_fcu001v1 system clock can be driven by an internal or external oscillator, as well as by the main PLL clock. By default, the system clock is driven by the PLL clock at 84MHz, driven by a 16MHz high-speed external clock.

Serial Port

The steval_fcu001v1 board has one UART. The Zephyr console output is assigned to UART1. Default settings are 115200 8N1.


The steval_fcu001v1 board has one I2C. The default I2C mapping for Zephyr is:

  • I2C2_SCL : PB10
  • I2C2_SDA : PB3

Programming and Debugging

Applications for the steval_fcu001v1 board configuration can be built and flashed in the usual way (see Building an Application and Run an Application for more details).


Flashing Zephyr onto the steval_fcu001v1 board requires an external ST-LINK/V2-1 programmer. The programmer is attached to the P8 programming header with ARM-JTAG-20-10-Plug-in Adapter.

Flashing an application to STEVAL_FCU001V1

Connect the FT232-to-USB port to host system, and RX, TX, Gnd pins to the P7 header of the steval_fcu001v1 board. Then run a serial host program to connect with your steval_fcu001v1 via the FT232 board:

$ minicom -D /dev/ttyUSB0

Now build and flash an application. Here is an example for Hello World

# From the root of the zephyr repository
west build -b steval_fcu001v1 samples/hello_world
west flash

You should see the following message on the console:

Hello World! steval_fcu001v1


You can debug an application in the usual way. Here is an example for the Hello World application.

# From the root of the zephyr repository
west build -b steval_fcu001v1 samples/hello_world
west debug