90 lines
2.7 KiB
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90 lines
2.7 KiB
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.. _led_apa102_sample:
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APA102 Sample Application
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#########################
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Overview
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********
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This sample application demonstrates basic usage of the APA102 LED
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strip driver, for controlling LED strips using APA102, Adafruit DotStar,
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and compatible driver chips.
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Requirements
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************
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.. _Dotstar product from AdaFruit: https://www.adafruit.com/category/885
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.. _74AHCT125: https://cdn-shop.adafruit.com/datasheets/74AHC125.pdf
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- LED strip using APA102 or compatible, such as the any `Dotstar product
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from AdaFruit`_.
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- Zephyr board with SPI master driver. SPI communications must use 5V
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signaling, which may require a level translator, such as the
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`74AHCT125`_.
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- 5V power supply.
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Wiring
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******
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#. Ensure your Zephyr board, the 5V power supply, and the LED strip
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share a common ground.
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#. Connect the MOSI pin of your board's SPI master to the data input
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pin of the first APA102 IC in the strip.
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#. Connect the SCLK pin of your board's SPI master to the clock input
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pin of the first APA102 IC in the strip.
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#. Connect the 5V power supply pin to the 5V input of the LED strip.
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Building and Running
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********************
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The sample application is located at ``samples/drivers/led_apa102/``
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in the Zephyr source tree.
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Configure For Your Board
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========================
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Now check if your board is already supported, by looking for a file
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named ``boards/YOUR_BOARD_NAME.conf`` in the application directory.
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If your board isn't supported yet, you'll need to configure the
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application as follows.
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#. Configure your board's SPI master in a configuration file under
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``boards/`` in the sample directory.
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To provide additional configuration for some particular board,
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create a ``boards/YOUR_BOARD_NAME.conf`` file in the application
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directory. It will be merged into the application configuration.
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In this file, you must ensure that the SPI peripheral you want to
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use for this demo is enabled. See ``boards/nucleo_l432kc.conf`` for
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an example.
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#. Configure your board's dts overlay. See ``nucleo_l432kc.overlay``
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for an example.
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#. Set the number of LEDs in your strip in the application sources.
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This is determined by the macro ``STRIP_NUM_LEDS`` in the file
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``src/main.c``.
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Then build and flash the application:
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.. zephyr-app-commands::
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:zephyr-app: samples/drivers/led_apa102
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:board: <board>
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:goals: flash
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:compact:
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Refer to your :ref:`board's documentation <boards>` for alternative
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flash instructions if your board doesn't support the ``flash`` target.
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When you connect to your board's serial console, you should see the
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following output:
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.. code-block:: none
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***** BOOTING ZEPHYR OS zepyhr-v1.13.XX *****
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[general] [INF] main: Found LED strip device APA102
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