Where can I find the actual API documentation that talks about how to write against the nRF Connect SDK?

RE: Where can I find the actual API documentation that talks about how to write against the nRF Connect SDK?

Kenneth — Mon, 17 Oct 2022 07:51:43 GMT

Hi again,

[quote user="the_reza"]Is this the best approach? Is there any way to get the ADC to just run and write to a FIFO without the cpu interacting? And I'm assuming this will work with SDK Connect? [/quote]

It's possible to setup timers, ppi and adc to execute an ADC measurement without MCU interaction at given intervals, but the handling (e.g. copying to a different buffer) must be done by the MCU. This is a good approach.

[quote user="the_reza"]I think I picked a bad time to start using the Nordic ICs -- the older SDK seemed so much more straightforward and so much better documented. Are people still coding against it or is the use of the Connect highly recommended?[/quote]

The nRF Connect is the one that is recommended and preferred yes. The old nRF5 SDK only get critcal fix updates, all new development is on the nRF Connect SDK.

Best regards,
Kenneth

RE: Where can I find the actual API documentation that talks about how to write against the nRF Connect SDK?

the_reza — Thu, 13 Oct 2022 08:54:05 GMT

Kenneth,

Thank you so much for pointing me at some relevant docs. I've been spending some time trying to understand all the parts - please let me know if i'm on the right or wrong track.

So the NRFX codebase lets me use peripherals without having to use the overlays? If so, this example seems the most relevant that I've found so far (github.com/.../nRF52-ADC-examples).

I then configure a timer to trigger adc conversions of a sequence of channels to a FIFO.

I would also configure a different timer to read from the fifo and send data to the BT stack?

Is this the best approach? Is there any way to get the ADC to just run and write to a FIFO without the cpu interacting? And I'm assuming this will work with SDK Connect?

In looking at PPIs, I've only really seen examples where they are used to connect an i/o change to an interrupt or visa-versa. Not sure how they can be used with the ADC or BT -- can they be? In the nrfx_saadc_multi_channel_ppi example, it seems that the PPI is only used to initiate an ADC conversion from the timer -- I'm not sure how this is better than having an timer ISR start the ADC conversion itself.

I think I picked a bad time to start using the Nordic ICs -- the older SDK seemed so much more straightforward and so much better documented. Are people still coding against it or is the use of the Connect highly recommended?

Thanks in advance,

Reza

RE: Where can I find the actual API documentation that talks about how to write against the nRF Connect SDK?

Kenneth — Wed, 12 Oct 2022 15:55:36 GMT

Hello,

I guess there are several ways and steps this can be done, but here are my input to get started.

I recommend that you checkout the zephyr example that use nrfx driver directly:
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/samples/boards/nrf/nrfx/README.html

In your case you need to use the nrfx_saadc instead with similiar approach:
https://github.com/NordicSemiconductor/nrfx/blob/master/drivers/include/nrfx_saadc.h

There should be threads here on devzone that show how to use the nrfx saadc driver. Once you are sampling the SAADC as you want, the next step will be how to transfer this data to zephyr, then I suggest to check out:
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/kernel/services/index.html#data-passing

Best regards,
Kenneth