I have a PIC with a 12 bits ADC resolution (16F18446).

I though, having some 10kΩ 10 turns potentiometer in my drawer, I would be able to visualize all 4096 points of the ADC measurement.

It dosen't.

Looking at the range via serial comm, I can see "holes" in the 0..4095 range like it would jump from i.e. 646 to 648 never showing 647.

My PIC has a lot of ADC features but I think I turned them OFF, all.

I have made some circuits with additional resistors hoping to reduce the ADC input range hence rising the résolution of the potentiometer itself, but it doesn't seem to do quite better.

Is there a way to "visualize" the whole ADC range of my PIC?