Regarding the Value Obtained from the ADC

RE: Regarding the Value Obtained from the ADC

kkuma256 — Tue, 20 Aug 2024 00:49:28 GMT

The direct cause has been identified.

Previously, the SAADC initialization was done with:

err_code = nrf_drv_saadc_init(null, saadc_callback);

However, when I explicitly initialized it like this:

nrf_drv_saadc_config_t saadc_config = NRF_DRV_SAADC_DEFAULT_CONFIG;
saadc_config.resolution = NRF_SAADC_RESOLUTION_12BIT;

I was able to get the expected values.

Thank you very much.

However, another issue has arisen, so I will ask about it in a separate issue.

RE: Regarding the Value Obtained from the ADC

Hieu — Thu, 15 Aug 2024 21:40:29 GMT

Hi kkuma256,

I reviewed your configuration carefully and see no issue. All of your configurations are correct, and your expected value is also correct.

The only thing I can see is that if the resolution is 10 bit, then the expected value would be 853. If this is the case, your result of 860 would make sense.

The value in NRFX_SAADC_CONFIG_RESOLUTION only change the default resolution when using NRFX_SAADC_DEFAULT_CONFIG.
Could you be configuring your own nrfx_saadc_config_t, of the resolution is set again somewhere?

Could you please look into your nrfx_saadc_config_t() and check if the resolution is correct?

Hieu

RE: Regarding the Value Obtained from the ADC

Hieu — Mon, 12 Aug 2024 18:41:11 GMT

Hi kkuma256,

I just want to let you know that I have received your question and will proceed with helping you soon.

Hieu