/* flip all bits except between range defined 
   by startBit and numBits to left*/
/* bit numbering like: 7 6 5 4 3 2 1 0 */

inline unsigned short flipNotInRange (unsigned short in, int startBit, int numBits)
{
  unsigned short result;
  
  result =(~in) ^ (~((unsigned short) ~0<<numBits )<< startBit);
  return result;
}