EmonLib on AtMega1284P

Hello, I’ve added atmega1284P support to emonlib by adding these two lines of code in EmonLib.cpp, readVcc function:

#elif defined(AVR_ATmega1284) || defined(AVR_ATmega1284P)
ADMUX = _BV(REFS0) | _BV(MUX4) | _BV(MUX3) | _BV(MUX2) | _BV(MUX1);

The library will then work with the 644/1284 MightyCore.

I didn’t check if they are also good for 644.
May you include them in a future release of the library?

Alessandro, Italy

Nice! Any chance you could put this into a GitHub pull request to the emonLib repo? If it does not adversely affect operation on other boards, we will get it merged into the main library