Problem with ADC result

[Louis Hatte]

Hello everyone,

We are using the nrf52832 Dev Kit (  PCA10040 1.2.1 2017.49 682663245)

SRK Version 15.3

OS : Fedora

On the saadc example in the peripheral folder always return the same value (15,16) when we wire the A0 pin ( p0.03 ) to GND or VCC.

We did not bring any modification to the example, except for using segger RTT to print the result.

[Einar Thorsrud]

Hi,

This seems to be caused by a misunderstanding about pin numbering. The SAADC example uses AIN0, which is P0.02 (see Pin assignments). The A0 pin marking on the DK refers to Arduino pin numbering, and not analog input pin numbers.

[awneil]

Einar Thorsrud said:

The A0 pin marking on the DK refers to Arduino pin numbering

See:

https://devzone.nordicsemi.com/f/nordic-q-a/46819/problems-with-saadc/184714#184714

Looks like something Nordic need to clarify in the documentation.

Perhaps if all three references - A0, AIN1, and P0.03 - were given together it would help ?