You can try this, it is far more complex, not tested yet, but would remove the selections from run-time ( smaller code )
//My TMP SerialSelector
template< int i_Number > class SerialSelector;
template<> struct SerialSelector< 0 >{ static inline HardwareSerial &Get( void ){ return Serial; } };
#if defined(__AVR_ATmega1280__) || defined(__AVR_ATmega2560__)
template<> struct SerialSelector< 1 >{ static inline HardwareSerial &Get( void ){ return Serial1; } };
template<> struct SerialSelector< 2 >{ static inline HardwareSerial &Get( void ){ return Serial2; } };
template<> struct SerialSelector< 3 >{ static inline HardwareSerial &Get( void ){ return Serial3; } };
#endif
//A rework of your class
template< int i_Number >
class MGCFA632{
public:
MGCFA632( int i_Rate = 9600 ) : _port( SerialSelector< i_Number >::Get() )
{ this->_port.begin( i_Rate ); }
protected:
private:
HardwareSerial &_port;
};
//And finally a declaration.
MGCFA632< 0 > m_Obj; //Uses Serial
MGCFA632< 1 > m_Obj; //Uses Serial1
MGCFA632< 2 > m_Obj; //Uses Serial2
MGCFA632< 3 > m_Obj; //Uses Serial3
If you can grasp the SerialSelector class you are on a win ( it is a compile time switch construct )