62 lines
1.8 KiB
ReStructuredText
62 lines
1.8 KiB
ReStructuredText
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.. _adc-sample:
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Analog-to-Digital Converter (ADC)
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#################################
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Overview
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********
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This sample demonstrates how to use the ADC driver API.
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Depending on the MCU type, it reads the ADC samples of one or two ADC channels
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and prints the readings to the console. If supported by the driver, the raw
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readings are converted to millivolts.
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The pins of the ADC channels are board-specific. Please refer to the board
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or MCU datasheet for further details.
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.. note::
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This sample does not work on Nordic platforms where there is a distinction
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between channel and analog input that requires additional configuration. See
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:zephyr_file:`samples/boards/nrf/battery` for an example of using the ADC
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infrastructure on Nordic hardware.
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Building and Running
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********************
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The ADC peripheral and pinmux is configured in the board's ``.dts`` file. Make
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sure that the ADC is enabled (``status = "okay";``).
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In addition to that, this sample requires an ADC channel specified in the
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``io-channels`` property of the ``zephyr,user`` node. This is usually done with
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a devicetree overlay. The example overlay in the ``boards`` subdirectory for
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the :ref:`nucleo_l073rz_board` can be easily adjusted for other boards.
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Building and Running for ST Nucleo L073RZ
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=========================================
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The sample can be built and executed for the
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:ref:`nucleo_l073rz_board` as follows:
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.. zephyr-app-commands::
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:zephyr-app: samples/drivers/adc
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:board: nucleo_l073rz
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:goals: build flash
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:compact:
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To build for another board, change "nucleo_l073rz" above to that board's name
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and provide a corresponding devicetree overlay.
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Sample output
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=============
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You should get a similar output as below, repeated every second:
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.. code-block:: console
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ADC reading(s): 42 (raw)
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.. note:: If the ADC is not supported, the output will be an error message.
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