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Elixir Cross Referencer

.. _nrf51_pca10028:



Zephyr applications use the nrf51_pca10028 board configuration to run on the
nRF51 Development Kit (PCA10028) hardware. It provides support for the Nordic Semiconductor
nRF51822 ARM Cortex-M0 CPU and the following devices:

* :abbr:`NVIC (Nested Vectored Interrupt Controller)`
* :abbr:`RTC (nRF RTC System Clock)`
* RADIO (Bluetooth Low Energy)
* Segger RTT (RTT Console)

.. figure:: img/nrf51_pca10028.jpg
     :width: 442px
     :align: center
     :alt: nRF51 PCA10028 DK

     nRF51 PCA10028 DK (Credit: Nordic Semi)

More information about the board can be found at the
`nRF51 DK website`_. The `Nordic Semiconductor Infocenter`_
contains the processor's information and the datasheet.


nRF51 DK has two external oscillators. The frequency of
the slow clock is 32.768 kHz. The frequency of the main clock
is 16 MHz.

Supported Features

The nrf51_pca10028 board configuration supports the following nRF51
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 `nRF51 DK website`_ and `Nordic Semiconductor Infocenter`_
for a complete list of nRF51 Development Kit board hardware features.

Connections and IOs


* LED1 (green) = P0.21
* LED2 (green) = P0.22
* LED3 (green) = P0.23
* LED4 (green) = P0.24

Push buttons

* BUTTON1 = SW1 = P0.17
* BUTTON2 = SW2 = P0.18
* BUTTON3 = SW3 = P0.19
* BUTTON4 = SW4 = P0.20
* BOOT = SW5 = boot/reset

Programming and Debugging


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

#. To build the Zephyr kernel, enter:

   .. code-block:: console

      $ cd $ZEPHYR_BASE
      $ make -C samples/subsys/shell/shell BOARD=nrf51_pca10028

#. Connect the micro-USB cable to the nRF51 DK and to your computer.

#. Erase the flash memory in the nRF51822:

   .. code-block:: console

      $ nrfjprog --eraseall -f nrf51

#. Flash the application using the nrfjprog tool:

   .. code-block:: console

      $ nrfjprog --program outdir/zephyr.hex -f nrf51

#. 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
   nRF51 DK can be found. For example, under Linux,

   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.


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

Testing the LEDs and buttons in the nRF51 DK

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


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/nrf51_pca10028/board.h`.


.. target-notes::

.. _nRF51 DK website:
.. _Nordic Semiconductor Infocenter: