SAADC Snippet cannot follow

Question

I tried implementing 
 https://github.com/andenore/NordicSnippets/blob/master/examples/temp/main.c 
 But i get 2.6V without connecting any of the Analog pins.

Exactly which pin is it designed for? 
 and why is it reading 2.6V with no input on pinA0.

hmolesworth · Accepted Answer

NRF_SAADC->CH[0].PSELP = PSELP_AnalogInput0 << SAADC_CH_PSELP_PSELP_Pos;

hmolesworth · Answer

That code is not reading pin A0; See this: // Configure the SAADC channel with VDD as positive input, no negative input(single ended). NRF_SAADC->CH[0].PSELP = SAADC_CH_PSELP_PSELP_VDD << SAADC_CH_PSELP_PSELP_Pos; NRF_SAADC->CH[0].PSELN = SAADC_CH_PSELN_PSELN_NC << SAADC_CH_PSELN_PSELN_Pos; This information will help: // Analog positive and negative input channels have strange numbering: // PSELP_NC 0UL Not connected // PSELP_AnalogInput0 1UL AIN0 // PSELP_AnalogInput1 2UL AIN1 // PSELP_AnalogInput2 3UL AIN2 // PSELP_AnalogInput3 4UL AIN3 // PSELP_AnalogInput4 5UL AIN4 // PSELP_AnalogInput5 6UL AIN5 // PSELP_AnalogInput6 7UL AIN6 // PSELP_AnalogInput7 8UL AIN7 // PSELP_VDD 9UL VDD

SAADC Snippet cannot follow

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