67 lines
2.1 KiB
ReStructuredText
67 lines
2.1 KiB
ReStructuredText
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.. zephyr:code-sample:: adc_sequence
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:name: Analog-to-Digital Converter (ADC) sequence sample
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:relevant-api: adc_interface
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Read analog inputs from ADC channels, using a sequence.
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Overview
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********
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This sample demonstrates how to use the :ref:`ADC driver API <adc_api>` using sequences.
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Depending on the target board, it reads ADC samples from two channels
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and prints the readings on the console, based on the sequence specifications.
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Notice how for the whole sequence reading, only one call to the :c:func:`adc_read` API is made.
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If voltage of the used reference can be obtained, the raw readings are converted to millivolts.
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This example constructs an adc device and setups its channels, according to the
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given devicetree configuration.
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Building and Running
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********************
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Make sure that the ADC is enabled (``status = "okay";``) and has each channel as a
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child node, with your desired settings like gain, reference, or acquisition time and
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oversampling setting (if used). It is also needed to provide an alias ``adc0`` for the
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desired adc. See :zephyr_file:`boards/nrf52840dk_nrf52840.overlay
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<samples/drivers/adc/adc_dt/boards/nrf52840dk_nrf52840.overlay>` for an example of
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such setup.
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Building and Running for Nordic nRF52840
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========================================
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The sample can be built and executed for the
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:ref:`nrf52840dk_nrf52840` as follows:
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.. zephyr-app-commands::
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:zephyr-app: samples/drivers/adc/adc_sequence
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:board: nrf52840dk/nrf52840
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:goals: build flash
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:compact:
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To build for another board, change "nrf52840dk/nrf52840" 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 sequence reading [1]:
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- ADC_0, channel 0, 5 sequence samples:
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- - 36 = 65mV
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- - 35 = 63mV
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- - 36 = 65mV
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- - 35 = 63mV
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- - 36 = 65mV
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- ADC_0, channel 1, 5 sequence samples:
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- - 0 = 0mV
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- - 0 = 0mV
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- - 1 = 1mV
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- - 0 = 0mV
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- - 1 = 1mV
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.. note:: If the ADC is not supported, the output will be an error message.
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