Tiny13 free running ADC will nicht wie ich will.

volatile uint8_t sekunden;

volatile uint8_t ADCWert;

//Timer-IRQ

ISR(TIM0_OVF_vect)

{

  static uint8_t tick;

  // 1,2 MHz / 256 = 4,687 => 5000 Durchgänge/s Prescaler 1024 => 5 Durchgänge/s

  // 1,2 MHz / 256 + Prescaler 256 => 20

  // 1,2 MHz / 256 + Prescaler 64 => 80

  // 1,2 MHz / 256 + Prescaler 8 => 640

  // 1,2 MHz / 256 + Prescaler 0 => 4700

  // 9,6 MHz => 36,6 ca. 37

  if(tick++ > 30)

  {

    sekunden++;

    tick=0;

    PORTB = PINB ^ ( 1 << PB1 );

  }

}

ISR(ADC_vect)

{

  ADCWert=ADCH;

}

void init(void)

{

  // Internal RC

  //PIN-Settings

  DDRB = 0; // Alles Eingänge

  //DDRB |= (1<<PB0); // PWm Ausgang

  DDRB |= (1<<PB1);

  DDRB |= (1<<PB3);//TESTAUSGÄNGE

  //PORTB|= (1<<PB3);//active low !

  //Timer0 Fast-PWM 50:50 Tast, Prescaler 1024

  TCCR0A = 0;

  TCCR0A = (1<<WGM00)|(1<<WGM01);//|(1<<COM0B1);//|(1<<COM0A0);

  TCCR0B = 0;

  TCCR0B = (1<<WGM02)|(1<<CS00)|(1<<CS02);

  OCR0A = 32;

  OCR0B = 16;

  TIMSK0 = 0;

  TIMSK0 = (1<<TOIE0);

  //ADC Free running, ADLAR=1 Mux=0 1,2MHz/8=150kHz

  ADCSRA = 0;

  ADCSRA = (1<<ADEN)|(1<<ADIE)|(1<<ADPS1)|(1<<ADPS0)|(1<<ADATE)|(1<<ADSC);

  ADCSRB = 0;

  //ADCSRB =();

  ADMUX = 0;

  ADMUX = (1<<ADLAR);//|(1<<)|(1<<);

  DIDR0 = (1<<ADC0D)|(1<<ADC1D)|(1<<ADC2D); //PB5,PB2,PB4

  //IRQs

  sei();

}

int main(void)

{

  init();

  while(1)

  {

      if(sekunden < ADCWert)

      {

        DDRB &= ~(1<<PB3);//TESTAUSGÄNGE

      }

      else

      {

       DDRB |= (1<<PB3);//TESTAUSGÄNGE

       sekunden=0;

      }

  }

}