this is a good question, the ATmega8U2 could be connected to the SPI bus of the ATmega328P, and just left floating until the right command comes along. This wouldn't interfere with backward compatibility or any devices at all.
this is a good question, the ATmega8U2 could be connected to the SPI bus of the ATmega328P, and just left floating until the right command comes along. This wouldn't interfere with backward compatibility or any devices at all.