Difficult between atmega328 & atmega2560 when coding & compiling in a pure c
I'm the author of the MateDealer project and I never had the intention to port it to other boards than the Arduino Mega2560! 

Ignacio Vazquez-Abrams is absolutely right, the Arduino Mega2560 is the only board with more than 1 serial port (Yes there is the Due and the Leonardo, but those would require major changes to the code).

The fastest way to get the code running is by using a Mega2560, but be warned, the code might be bugy as hell ;-)