Supports alternativ PWM frequencies for MEGA2560
  Attention! Timer0 is also used for other tasks (millis, micros, delay).
 
  Timer0 = D4 and D13 
  Timer1 = D11, D12
  Timer2 = D9, D10
  Timer3 = D2, D3, D5
  Timer4 = D6, D7, D8
  Timer5 = D44, D45, D46
 
  Prescaler 1= 31372,55Hz, 2= 3921,16Hz, 3= 490Hz, 4= 122.55Hz 5= 30Hz (in case of timer0 the PWM frequency for prescaler values 1-5 are doubled)