ST Nucleo F401RE

Overview

The Nucleo F401RE board features an ARM Cortex-M4 based STM32F401RE MCU with a wide range of connectivity support and configurations Here are some highlights of the Nucleo F401RE board:

STM32 microcontroller in QFP64 package
Two types of extension resources:
- Arduino Uno V3 connectivity
- ST morpho extension pin headers for full access to all STM32 I/Os
On-board ST-LINK/V2-1 debugger/programmer with SWD connector
Flexible board power supply:
- USB VBUS or external source(3.3V, 5V, 7 - 12V)
- Power management access point
Three LEDs: USB communication (LD1), user LED (LD2), power LED (LD3)
Two push-buttons: USER and RESET

More information about the board can be found at the Nucleo F401RE website.

Hardware

Nucleo F401RE provides the following hardware components:

STM32F401RET6 in LQFP64 package
ARM® 32-bit Cortex®-M4 CPU with FPU
84 MHz max CPU frequency
VDD from 1.7 V to 3.6 V
512 KB Flash
96 KB SRAM
GPIO with external interrupt capability
12-bit ADC with 16 channels
RTC
Advanced-control Timer
General Purpose Timers (7)
Watchdog Timers (2)
USART/UART (3)
I2C (3)
SPI (4)
SDIO
USB 2.0 OTG FS
DMA Controller

More information about STM32F401RE can be found here:

Supported Features

The Zephyr nucleo_401re 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
ADC	on-chip	ADC Controller
WATCHDOG	on-chip	System Window Watchdog
die-temp	on-chip	die temperature sensor
RTC	on-chip	rtc

Other hardware features are not yet supported on Zephyr porting.

The default configuration can be found in boards/st/nucleo_f401re/nucleo_f401re_defconfig

Pin Mapping

Nucleo F401RE Board has 6 GPIO controllers. These controllers are responsible for pin muxing, input/output, pull-up, etc.

Available pins:

For more details please refer to STM32 Nucleo-64 board User Manual.

Default Zephyr Peripheral Mapping:

UART_1 TX/RX : PB6/PB7
UART_2 TX/RX : PA2/PA3 (ST-Link Virtual Port Com)
I2C1 SCL/SDA : PB8/PB9 (Arduino I2C)
SPI1 CS/SCK/MISO/MOSI : PB6/PA5/PA6/PA7 (Arduino SPI)
PWM_2_CH1 : PA0
USER_PB : PC13
LD2 : PA5

System Clock

Nucleo F401RE System Clock could be driven by internal or external oscillator, as well as main PLL clock. By default System clock is driven by PLL clock at 84MHz, driven by 8MHz high speed external clock.

Serial Port

Nucleo F401RE board has 3 UARTs. The Zephyr console output is assigned to UART2. Default settings are 115200 8N1.

I2C

Nucleo F401RE board has up to 3 I2Cs. The default I2C mapping for Zephyr is:

I2C1_SCL : PB8
I2C1_SDA : PB9

Programming and Debugging

Nucleo F401RE board includes an ST-LINK/V2-1 embedded debug tool interface.

Applications for the nucleo_f401re board configuration can be built and flashed in the usual way (see Building an Application and Run an Application for more details).

Flashing

The board is configured to be flashed using west STM32CubeProgrammer runner, so its installation is required.

Alternatively, OpenOCD or JLink can also be used to flash the board using the --runner (or -r) option:

$ west flash --runner openocd
$ west flash --runner jlink

Flashing an application to Nucleo F401RE

Connect the Nucleo F401RE to your host computer using the USB port, then run a serial host program to connect with your Nucleo board:

$ minicom -D /dev/ttyACM0

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

# From the root of the zephyr repository
west build -b nucleo_f401re samples/hello_world
west flash

You should see the following message on the console:

Hello World! arm

Debugging

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 nucleo_f401re samples/hello_world
west debug