Marlin_Firmware/Marlin/macros.h

#ifndef MACROS_H
#define MACROS_H

// Macros for bit masks
#define TEST(n,b) (((n)&_BV(b))!=0)
#define SBI(n,b) (n |= _BV(b))
#define CBI(n,b) (n &= ~_BV(b))
#define SET_BIT(n,b,value) (n) ^= ((-value)^(n)) & (_BV(b))

// Macros for maths shortcuts
#define RADIANS(d) ((d)*M_PI/180.0)
#define DEGREES(r) ((r)*180.0/M_PI)

// Macros to contrain values
#define NOLESS(v,n) do{ if (v < n) v = n; }while(0)
#define NOMORE(v,n) do{ if (v > n) v = n; }while(0)

// Macros to support option testing
#define _CAT(a, ...) a ## __VA_ARGS__
#define SWITCH_ENABLED_0 0
#define SWITCH_ENABLED_1 1
#define SWITCH_ENABLED_  1
#define ENABLED(b) _CAT(SWITCH_ENABLED_, b)
#define DISABLED(b) (!_CAT(SWITCH_ENABLED_, b))

#define COUNT(a) (sizeof(a)/sizeof(*a))

#endif //__MACROS_H