.. _nrf52_adafruit_feather: nRF52 Adafruit Feather ###################### Overview ******** The nRF52 Adafruit Bluefruit Feather hardware provides support for the Nordic Semiconductor nRF52832 ARM Cortex-M4F CPU and the following devices: * :abbr:`NVIC (Nested Vectored Interrupt Controller)` * :abbr:`RTC (nRF RTC System Clock)` * UART * GPIO * FLASH * RADIO (Bluetooth Low Energy) * Segger RTT (RTT Console) .. figure:: img/nrf52_adafruit_feather.jpg :align: center :alt: nRF52 Adafruit Feather Board nRF52 Adafruit Feather Board (Credit: Adafruit) More information about the board and its features can be found at the `Adafruit Feather nRF52 Bluefruit Learning Guide`_. The `Nordic Semiconductor Infocenter`_ contains the processor's information and the datasheet. Hardware ******** - nRF52832 ARM Cortex-M4F processor at 64 MHz - 32.768 kHz crystal oscillator - 512 KiB flash memory and 64 KiB of SRAM - Battery connector and charger for 3.7 V lithium polymer batteries - Charging indicator LED - 2 User LEDs - Reset button - SWD connector - USB serial converter Supported Features ================== The nRF52 Adafruit Feather board configuration supports the following hardware features: +-----------+------------+----------------------+ | Interface | Controller | Driver/Component | +===========+============+======================+ | NVIC | on-chip | nested vectored | | | | interrupt controller | +-----------+------------+----------------------+ | RTC | on-chip | system clock | +-----------+------------+----------------------+ | UART | on-chip | serial port | +-----------+------------+----------------------+ | GPIO | on-chip | gpio | +-----------+------------+----------------------+ | FLASH | on-chip | flash | +-----------+------------+----------------------+ | RADIO | on-chip | Bluetooth | +-----------+------------+----------------------+ | RTT | on-chip | console | +-----------+------------+----------------------+ Other hardware features have not been enabled yet for this board. Connections and IOs =================== The `Adafruit Feather nRF52 Bluefruit Learning Guide`_ has detailed information about the board including `pinouts`_ and the `schematic`_. LED --- * LED0 (red) = P0.17 * LED1 (blue) = P0.19 Push buttons ------------ * DFU = SW0 = P0.20 * RESET = SW1 = P0.21/reset Programming and Debugging ************************* The ``nrf52_adafruit_feather`` board is available in two different versions: - `Adafruit Feather nRF52 Pro with myNewt Bootloader`_ This board version is the recommended one to use. It has the SWD header already populated and comes with the Mynewt serial bootloader installed by default. - `Adafruit Feather nRF52 Bluefruit LE`_ This board is identical to the board above, but the SWD header is not populated and ships with an Arduino friendly bootloader. To be able to work with this version a 2*5pin 0.5" SWD header (e.g. `Adafruit SWD connector`_) needs to be soldered. Applications for the ``nrf52_adafruit_feather`` board configuration can be built, flashed, and debugged in the usual way. See :ref:`build_an_application` and :ref:`application_run` for more details on building and running. Flashing ======== Flashing Zephyr onto the ``nrf52_adafruit_feather`` board requires an external J-Link programmer. The programmer is attached to the X1 SWD header. Follow the instructions in the :ref:`nordic_segger` page to install and configure all the necessary software. Further information can be found in :ref:`nordic_segger_flashing`. Then build and flash applications as usual (see :ref:`build_an_application` and :ref:`application_run` for more details). Here is an example for the :ref:`hello_world` application. #. Build the Zephyr kernel and the :ref:`hello_world` sample application: .. zephyr-app-commands:: :zephyr-app: samples/hello_world :board: nrf52_adafruit_feather :goals: build :compact: #. Connect the Adafruit nRF52 Feather to your host computer using USB #. Run your favorite terminal program to listen for output. .. code-block:: console $ minicom -D -b 115200 Replace :code:`` with the port where the nRF52 Adafruit Feather board can be found. For example, under Linux, :code:`/dev/ttyUSB0`. #. Flash the image: .. zephyr-app-commands:: :zephyr-app: samples/hello_world :board: nrf52_adafruit_feather :goals: flash :compact: You should see "Hello World! nrf52_adafruit_feather" in your terminal. Debugging ========= The ``nrf52_adafruit_feather`` board does not have an on-board J-Link debug IC as some nRF5x development boards, however, instructions from the :ref:`nordic_segger` page also apply to this board, with the additional step of connecting an external debugger. Testing the LEDs and buttons on the nRF52 Adafruit Feather ********************************************************** There are several samples that allow you to test that the buttons (switches) and LEDs on the board are working properly with Zephyr: - :zephyr:code-sample:`blinky` - :zephyr:code-sample:`button` - :zephyr:code-sample:`fade-led` - :zephyr:code-sample:`pwm-blinky` - :zephyr:code-sample:`multi-thread-blinky` You can build and flash the examples to make sure Zephyr is running correctly on your board. The button and LED definitions can be found in :zephyr_file:`boards/arm/nrf52_adafruit_feather/board.h`. References ********** .. target-notes:: .. _Adafruit Feather nRF52 Bluefruit Learning Guide: https://learn.adafruit.com/bluefruit-nrf52-feather-learning-guide/introduction .. _schematic: https://learn.adafruit.com/assets/39913 .. _pinouts: https://cdn-learn.adafruit.com/assets/assets/000/046/210/original/Feather_NRF52_Pinout_v1.2.pdf?1504807075 .. _Nordic Semiconductor Infocenter: https://infocenter.nordicsemi.com .. _J-Link Software and documentation pack: https://www.segger.com/jlink-software.html .. _Adafruit Feather nRF52 Bluefruit LE: https://www.adafruit.com/product/3406 .. _Adafruit Feather nRF52 Pro with myNewt Bootloader: https://www.adafruit.com/product/3574 .. _Adafruit SWD connector: https://www.adafruit.com/product/752