arduino mini using ad6 ad7 for digital i/o

hi, does anybody know if i can use the additional analog pins of my arduino mini as digital i/o pins, just like i can with the pins ad0 to ad5?

it seems that i cannot use them when i address them with 20/21, e.g. digitalWrite(21, HIGH);

Can they ONLY be used for analog readings?


Can they ONLY be used for analog readings?

From a hardware point of view there is no reason why they can't be used as digital I/O so it must be down to the software.

did you set them with pinMode ?

yes, i did set them with pinMode... I have an array of pins where I just put in (20,21), so everything should work if those pins can be used for digital output.

in the port mapping of the arduino mini/atmega168 those two pins only say ADC6/ADC7. "regular" pins have this notation: PC3(ADC3)