// Musical keys and their frequencies

#define C4   262
#define D4   294
#define E4   330
#define F4   349
#define G4   392
#define A4   440
#define B4   494

#define C5   523
#define D5   587
#define E5   659
#define F5   698
#define G5   784
#define A5   880
#define B5   988

#define C6   1046
#define D6   1175
#define E6   1318
#define F6   1397
#define G6   1568
#define A6   1760
#define B6   1967