Hello,
I want to use the ADC pins of ATmega328 as digital outputs and inputs. Do I need to turn off the ADC using the ADEN bit? is there anything we have to do to use it as regular digital IO?
you don´t necessarily need turn off the ADC.
I´m not sure if it is turned on by defalut. It surely is written in the datasheet.
If I´m not mistaken there is the option to turn OFF the digital input section when a pin is used as pure analog input.
I´d need to read the datasheet, at least the ADC section.