Adafruit Feather nRF52840 Express

Overview

The Adafruit Feather nRF52840 provides support for the Nordic Semiconductor nRF52840 ARM Cortex-M4F CPU and the following devices:

  • ADC

  • CLOCK

  • FLASH

  • GPIO

  • I2C

  • MPU

  • NVIC

  • PWM

  • RADIO (Bluetooth Low Energy and 802.15.4)

  • RTC

  • Segger RTT (RTT Console)

  • SPI

  • UART

  • USB

  • WDT

Adafruit Feather nRF52840 Express

Hardware

  • nRF52840 ARM Cortex-M4F processor at 64 MHz

  • 1 MB flash memory and 256 KB of SRAM

  • Battery connector and charger for 3.7 V lithium polymer batteries

  • Charging indicator LED

  • 2 User LEDs

  • 1 NeoPixel LED

  • Reset button

  • SWD connector

Supported Features

The Adafruit Feather nRF52840 board configuration supports the following hardware features:

Interface

Controller

Driver/Component

ADC

on-chip

adc

CLOCK

on-chip

clock_control

FLASH

on-chip

flash

GPIO

on-chip

gpio

I2C

on-chip

i2c

MPU

on-chip

arch/arm

NVIC

on-chip

arch/arm

PWM

on-chip

pwm

RADIO

on-chip

Bluetooth, ieee802154

RTC

on-chip

system clock

SPI

on-chip

spi

UART

on-chip

serial

USB

on-chip

usb

WDT

on-chip

watchdog

Other hardware features are not supported by the Zephyr kernel.

Connections and IOs

The Adafruit Feather nRF52840 Express Learn site 1 has detailed information about the board including pinouts 2 and the schematic 3.

LED

  • LED0 (red) = P1.15

  • LED1 (blue) = P1.10

Push buttons

  • SWITCH = P1.02

  • RESET = P0.18

Programming and Debugging

Applications for the adafruit_feather_nrf52840 board configuration can be built and flashed in the usual way (see Building an Application and Run an Application for more details).

Flashing

Flashing Zephyr onto the adafruit_feather_nrf52480 board requires an external programmer. The programmer is attached to the SWD header.

Build the Zephyr kernel and the Blinky sample application.

west build -b adafruit_feather_nrf52840 samples/blinky

Flash the image.

west build -b adafruit_feather_nrf52840 samples/blinky
west flash

You should see the the red LED blink.

References

1

https://learn.adafruit.com/introducing-the-adafruit-nrf52840-feather/

2

https://learn.adafruit.com/introducing-the-adafruit-nrf52840-feather/pinouts

3

https://learn.adafruit.com/introducing-the-adafruit-nrf52840-feather/downloads