SAADC Snippet cannot follow

[Nats]

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]

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