ADC Usage on Atom UP2

niharG

I have the Atom-based UP2 and with the aaeon UP2 kernel, I am able to see ADC values in /sys/bus/iio/devices/iio:device0/in_voltage*. However, I can't find any documentation on the voltage ranges or scaling in the datasheets, wikis, or even the ADC instructions here https://downloads.up-community.org/download/how-to-access-adc-for-up-squared-atom/.

I'm specifically looking for:

1. What is the ADC range (0-3.3V? 0-5V?).
2. Are the ADC pins 5V tolerant even if the full scale range is lower than 5V?
3. How does one interpret the in_voltage*_raw values? I'm not sure what the scale factor is.
4. Can the ADC resolution be configured? I assume this is what in_voltage_scale is for, but I'm not sure how to use it (cannot cat the file).

I appreciate any information that can be shared about the ADC!