.. _nrf52840_pca10056:

nRF52840-PCA10056
#################

Overview
********

Zephyr applications use the nrf52840_pca10056 board configuration
to run on the nRF52840 Preview Development Kit (PCA10056) hardware. It provides
support for the Nordic Semiconductor nRF52840 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/nrf52840_pca10056.jpg
     :width: 442px
     :align: center
     :alt: nRF52840 PCA10056 Preview DK

     nRF52840 PCA10056 Preview DK (Credit: Nordic Semi)

More information about the board can be found at the
`nRF52840 PDK website`_. The `Nordic Semiconductor Infocenter`_
contains the processor's information and the datasheet.

Hardware
********

nRF52840 PDK has two external oscillators. The frequency of
the slow clock is 32.768 kHz. The frequency of the main clock
is 32 MHz.

Supported Features
==================

The nrf52840_pca10056 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 are not supported by the Zephyr kernel.
See `nRF52840 PDK website`_ and `Nordic Semiconductor Infocenter`_
for a complete list of nRF52840 Development Kit board hardware features.

Connections and IOs
===================

LED
---

* LED1 (green) = P0.13
* LED2 (green) = P0.14
* LED3 (green) = P0.15
* LED4 (green) = P0.16

Push buttons
------------

* BUTTON1 = SW1 = P0.11
* BUTTON2 = SW2 = P0.12
* BUTTON3 = SW3 = P0.24
* BUTTON4 = SW4 = P0.25
* BOOT = SW5 = boot/reset

Programming and Debugging
*************************

Flashing
========

Follow the instructions in the :ref:`nordic_segger` page to install and configure
all the necessary software.

This tutorial uses the sample application
shell :file:`$ZEPHYR_BASE/samples/subsys/shell/shell`, and uses the information that can be found in
:ref:`nordic_segger_flashing`.

#. To build the Zephyr kernel, enter:

   .. code-block:: console

      $ cd $ZEPHYR_BASE
      $ make -C samples/subsys/shell/shell BOARD=nrf52840_pca10056

#. Connect the micro-USB cable to the nRF52840 PDK and to your computer.

#. Erase the flash memory in the nRF52840:

   .. code-block:: console

      $ nrfjprog --eraseall -f nrf52

#. Flash the application using the nrfjprog tool:

   .. code-block:: console

      $ nrfjprog --program outdir/zephyr.hex -f nrf52

#. Run your favorite terminal program to listen for output.

   .. code-block:: console

      $ minicom -D <tty_device> -b 115200

   Replace :code:`<tty_device>` with the port where the board
   nRF52840 PDK can be found. For example, under Linux,
   :code:`/dev/ttyACM0`.

   The ``-b`` option sets baudrate ignoring the value
   from config.

#. Press the Reset button and you should see the output of
   shell application in your terminal.

Debugging
=========

Refer to the :ref:`nordic_segger` page to learn about debugging Nordic boards with a
Segger IC.


Testing the LEDs and buttons in the nRF52840 PDK
************************************************

There are 2 samples that allow you to test that the buttons (switches) and LEDs on
the board are working properly with Zephyr:

.. code-block:: console

   samples/basic/blinky
   samples/basic/button

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 :file:`boards/arm/nrf52840_pca10056/board.h`.


References
**********

.. target-notes::

.. _nRF52840 PDK website: http://www.nordicsemi.com/eng/Products/nRF52840-Preview-DK
.. _Nordic Semiconductor Infocenter: http://infocenter.nordicsemi.com/
.. _J-Link Software and documentation pack: https://www.segger.com/jlink-software.html