Music notes defined as constants

notefreq.h

#define A3 110
#define B3 123
#define C3 131
#define D3 147
#define E3 165
#define F3 175
#define FS3 185
#define G3 392
#define A4 220
#define B4 247
#define C4 262
#define D4 294
#define E4 330
#define F4 349
#define FS4 370
#define G4 392
#define A5 440
#define B5 494
#define C5 523
#define CS5 554
#define D5 587
#define E5 659
#define F5 698
#define FS5 740
#define G5 784
#define A6 880
#define B6 988
#define C6 1047
#define D6 1175
#define E6 1319
#define F6 1397
#define G6 1568
#define A7 1760
#define B7 1976
#define C7 2093
#define CS7 2218
#define D7 2349
#define E7 2637
#define F7 2794
#define G7 3136