Feather STM32F405 Express

Overview

The Adafruit Feather STM32F405 is an ARM Development board in the Feather standard layout, sharing peripheral placement with other devices labeled as Feathers or FeatherWings. The board is equipped with a lithium ion battery charger, native USB C connector, 2MB of external flash memory, and SD card socket.

Hardware

  • STM32F405 Cortex M4 with FPU and 1MB Flash, 168MHz speed

  • 192KB RAM total - 128 KB RAM + 64 KB program-only/cache RAM

  • USB C power and data

  • LiPo connector and charger

  • SD socket on the bottom, connected to SDIO port

  • 2 MB SPI Flash chip

  • Built in NeoPixel indicator

  • I2C, UART, GPIO, ADCs, DACs

  • Qwiic/STEMMA-QT connector for fast I2C connectivity

  • SWD SMT mount region on board underside.

Supported Features

The adafruit_feather_stm32f405 board supports the hardware features listed below.

on-chip / on-board
Feature integrated in the SoC / present on the board.
2 / 2
Number of instances that are enabled / disabled.
Click on the label to see the first instance of this feature in the board/SoC DTS files.
vnd,foo
Compatible string for the Devicetree binding matching the feature.
Click on the link to view the binding documentation.

Connections and IOs

The Adafruit Feather STM32F405 Express Learn site [1] has detailed information about the board including pinouts [2] and the schematic [3].

System Clock

The STM32F405 is configured to use the 12MHz HSE Oscillator to produce a 168MHz system clock.

Serial Port

The STM32F405 UART 3 peripheral is available on the TX (PB10) and RX (PB11) pins.

I2C Port

The STM32F405 I2C1 peripheral is available on the SDA (PB7) and SCL (PB6) pins.

SPI Port

The STM32F405 SPI2 peripheral is available on the SCK (PB13), MI (PB14) and MO (PB15) pins.

SPI1 uses SCK (PB3), MI (PB4), MO (PB5) and SS (PA15) pins and is dedicated to the 2 MB SPI Flash chip.

Programming and Debugging

The adafruit_feather_stm32f405 board supports the runners and associated west commands listed below.

flash debug

DFU-Util programming is supported through Zephyr by default. Set up of the built in DFU-Util bootloader is possible by following the instructions on the Learn website [4].

Flashing

  1. Build the Zephyr kernel and the Blinky sample application:

    west build -b adafruit_feather_stm32f405 samples/basic/blinky

  2. On the Adafruit Feather STM32F405, connect the 3.3V pin to the B0 boot pin with a jumper wire.

  3. Flash the image:

    west build -b adafruit_feather_stm32f405 samples/basic/blinky
west flash

    You should see the D13 LED blinking.

References