Bitmath Operations

bitmath.cpp

// Source & much additional info:
// http://playground.arduino.cc/Code/BitMath

y = (x >> n) & 1;    // n=0..7.  stores nth bit of x in y.  y becomes 0 or 1.
x &= ~(1 << n);      // forces nth bit of x to be 0.  all other bits left alone.
x &= (1<<(n+1))-1;   // leaves alone the lowest n bits of x; all higher bits set to 0.
x |= (1 << n);       // forces nth bit of x to be 1.  all other bits left alone.
x ^= (1 << n);       // toggles nth bit of x.  all other bits left alone.
x = ~x;              // toggles ALL the bits in x.