RE: How to check ADC sampling status.

Sigurd Hellesvik — Wed, 29 Dec 2021 12:25:46 GMT

Hi Swati

All functions and variables I reference in the following text can be found in Zephyr ADC API reference.

When you are calling the adc_read function, you need to configure the ADC using the adc_sequence argument.

adc_sequence has seven different configurations for the adc. These are

channels
buffer
buffer_size
resolution
oversampling
calibrate
options

options are additional options for the ADC configuration, and has the type adc_sequence_options.

adc_sequence_options has four different additional configurations:

interval_us
callback
user_data
extra_samplings

the callback configuration will be to a callback function which must be on the form:

typedef enum adc_action (*adc_sequence_callback)(const struct device *dev, const struct adc_sequence *sequence, uint16_t sampling_index)

When this have been configured, this callback function will be called after a requested sampling by the ADC is done.

[quote user=""]2. I want to understand about the Zeyphr adc_context_on_sampling_done() API how it is working in drivers/adc/adc_context.h.[/quote]

The adc_context_on_sampling_done() function is not a part of the public ADC driver. It is only used for internal operations in the driver.

Here is an example showcasing how the adc with callback can be used with the adc_read function:

devzone.nordicsemi.com/.../2705.adc.zip

Does this answer your questions?

Regards,
Sigurd Hellesvik