I've always used either 4.7k or 10k on my RESET pins on AVRs, but glancing at the datasheet of the ATmega325P ( the AVR i'm using) , I see that the pullup should be between 20K ohm and 100 K ohm.
So what's happening there? I'm using a 10K resistor and everything seems fine, but I wonder why the datasheet writes that the minimum is 20k.