43 lines
1.1 KiB
ReStructuredText
43 lines
1.1 KiB
ReStructuredText
.. _blinky-sample:
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Blinky sample
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#############
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Overview
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********
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Blinky is a simple application which blinks an LED forever.
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The source code shows how to configure GPIO pins as outputs, then turn them on
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and off.
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.. _blinky-sample-requirements:
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Requirements
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************
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You will see this error if you try to build Blinky for an unsupported board:
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.. code-block:: none
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Unsupported board: led0 devicetree alias is not defined
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The board must have an LED connected via a GPIO pin. These are called "User
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LEDs" on many of Zephyr's :ref:`boards`. The LED must be configured using the
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``led0`` :ref:`devicetree <dt-guide>` alias. This is usually done in the
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:ref:`BOARD.dts file <devicetree-in-out-files>` or a :ref:`devicetree overlay
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<set-devicetree-overlays>`.
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Building and Running
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********************
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Build and flash Blinky as follows, changing ``reel_board`` for your board:
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.. zephyr-app-commands::
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:zephyr-app: samples/basic/blinky
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:board: reel_board
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:goals: build flash
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:compact:
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After flashing, the LED starts to blink. Blinky does not print to the console.
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