Stoerung von RTC

int main( void )

{

  clock_init_1MHz();

  //RTC_init();

  USART_Init(12); // 9600bps bei 1MHz

  __enable_interrupt();

  for(;;)

  {

     Delay(1000);

     Usart_Tx(0x5A);

  }

}

void clock_init_1MHz(void)

{

  CLKPR = (1<<CLKPCE);        // set Clock Prescaler Change Enable

  // set prescaler = 8, Inter RC 8Mhz / 8 = 1Mhz

  CLKPR = (1<<CLKPS1) | (1<<CLKPS0); 

}

void Delay(unsigned int millisec)

{

    int i;

    while (millisec--)

        for (i=0; i<125; i++);

}

void USART_Init(unsigned int baudrate)

{

    // Set baud rate

    UBRR0H = (unsigned char)(baudrate>>8);

    UBRR0L = (unsigned char)baudrate;

    // Enable 2x speed

    UCSR0A = (1<<U2X0);

    // Enable receiver and transmitter

    UCSR0B = (1<<RXEN0)|(1<<TXEN0)|(0<<RXCIE0)|(0<<UDRIE0);

    // Async. mode, 8N1

    UCSR0C = (0<<UMSEL0)|(0<<UPM00)|(0<<USBS0)|(3<<UCSZ00)|(0<<UCPOL0);

}

void Usart_Tx(char data)

{

    while (!(UCSR0A & (1<<UDRE0)));

    UDR0 = data;

}

void RTC_init(void)

{

    Delay(1000);            // wait for 1 sec to let the Xtal stabilize after a power-on,

    __disable_interrupt();  // disabel global interrupt

    cbi(TIMSK2, TOIE2);             // disable OCIE2A and TOIE2

    ASSR = (1<<AS2);        // select asynchronous operation of Timer2

    TCNT2 = 0;              // clear TCNT2A

    TCCR2A |= (1<<CS22) | (1<<CS20);             // select precaler: 32.768 kHz / 128 = 1 sec between each overflow

    while((ASSR & (0x01 | 0x04)));       // wait for TCN2UB and TCR2UB to be cleared

    TIFR2 = 0xFF;           // clear interrupt-flags

    sbi(TIMSK2, TOIE2);     // enable Timer2 overflow interrupt

    OCR2A = 200;    // set timer2 compare value

    __enable_interrupt();                 // enable global interrupt

}