Simple analog read on nrf52

[Remo]

Hello. How i can do a simple read an 0 -> 3 Volt (vdd) signal on Analog 0 P0.03? I try it with saadc without sucess

            int result = 0;
		
			NRF_SAADC->CH[0].CONFIG = (
						SAADC_CH_PSELN_PSELN_AnalogInput0 << SAADC_CH_CONFIG_BURST_Pos |
						SAADC_CH_CONFIG_BURST_Enabled << SAADC_CH_CONFIG_BURST_Pos |
						SAADC_CH_CONFIG_MODE_SE << SAADC_CH_CONFIG_MODE_Pos |
						SAADC_CH_CONFIG_TACQ_10us << SAADC_CH_CONFIG_TACQ_Pos |
						SAADC_CH_CONFIG_REFSEL_Internal << SAADC_CH_CONFIG_TACQ_Pos |
						SAADC_CH_CONFIG_GAIN_Gain1_5 << SAADC_CH_CONFIG_GAIN_Pos |
						SAADC_CH_CONFIG_RESN_Bypass << SAADC_CH_CONFIG_RESN_Pos |
						SAADC_CH_CONFIG_RESP_Bypass << SAADC_CH_CONFIG_RESP_Pos );

			NRF_SAADC->CH[0].PSELP = SAADC_CH_PSELP_PSELP_VDD;
			NRF_SAADC->CH[0].PSELN = SAADC_CH_PSELN_PSELN_NC;
		
			// Configure the SAADC resolution.
			NRF_SAADC->RESOLUTION = SAADC_RESOLUTION_VAL_14bit << SAADC_RESOLUTION_VAL_Pos;
			NRF_SAADC->OVERSAMPLE = SAADC_OVERSAMPLE_OVERSAMPLE_Over256x << SAADC_OVERSAMPLE_OVERSAMPLE_Pos;

			//Setup memory location
			NRF_SAADC->RESULT.PTR = (uint32_t)&result;

			// No automatic sampling, will trigger with TASKS_SAMPLE.
			NRF_SAADC->SAMPLERATE = SAADC_SAMPLERATE_MODE_Task << SAADC_SAMPLERATE_MODE_Pos;

			// Enable SAADC (would capture analog pins if they were used in CH[0].PSELP)
			NRF_SAADC->ENABLE = SAADC_ENABLE_ENABLE_Enabled << SAADC_ENABLE_ENABLE_Pos;

[Jørgen Holmefjord]

Hi,

You can find an example of a simple read using the SAADC on the NordicSnippets GitHub page.

If you want to use the SAADC driver, included in the SDK, you can find a simple example in this thead.

Best regards,

Jørgen

[Remo]

...mmmh maybe i am completely wrong, but i try the code on the example without an result i get an result on the varaible "result" this result is about 12000 and changes +/- 10 on every round.