TCCR1B = _BV(WGM13) | _BV(WGM12);
TCNT1 = N_CYCLES_PERIOD-1;
TCCR1A = _BV(COM1A1) | _BV(WGM11);
TCCR1B = _BV(WGM13) | _BV(WGM12) | _BV(CS10);
TCCR1B = _BV(WGM13) | _BV(WGM12);
TCNT1 = N_CYCLES_PERIOD-1;
TCCR1A = _BV(COM1A1) | _BV(WGM11);
TCCR1B = _BV(WGM13) | _BV(WGM12) | _BV(CS10);