Suche fertiges RTC-Projekt (DS1307) für ATmega8 in C

void DS1307_Init( void )

{

    I2CSendAddr( DS1307_ADDR , WRITE );

    if( I2CCheckError() > 0 ){

        I2CSendStop();

        //Fehler

        return;

    }

    I2CSendByte( 0x00 );    //Adresse 0

    I2CSendByte( 0x00 );

    I2CSendByte( 0x00 );

    I2CSendByte( 0x00 );

    I2CSendByte( 0x00 );

    I2CSendByte( 0x00 );

    I2CSendByte( 0x00 );

    I2CSendByte( 0x00 );

    I2CSendByte( 0x10 );    //SQWE=1

    I2CSendStop();

}

struct ds1307 {    

                unsigned char sekunde;

                unsigned char minute;

                unsigned char stunde;

                unsigned char tag;

                unsigned char monat;

                unsigned int  jahr;    

                unsigned char wtag; //(0=Montag;...;6=Sonntag)

                unsigned char isdst;

                };

struct ds1307 rtc;

void DS1307GetTime ( void )

{   

    unsigned char __data rtc_temp;

    rtc.sekunde = DS1307ReadByte ( 0x00 );

    rtc.minute  = DS1307ReadByte ( 0x01 );

    rtc.stunde  = DS1307ReadByte ( 0x02 );

    rtc.wtag    = DS1307ReadByte ( 0x03 );

    rtc.tag     = DS1307ReadByte ( 0x04 );

    rtc.monat   = DS1307ReadByte ( 0x05 );

    rtc_temp    = DS1307ReadByte ( 0x06 );

    rtc.jahr    = (rtc_temp & 0xF0 );

    rtc.jahr    |= (unsigned char )(rtc_temp & 0x0F );

}

void DS1307SetTime ( void )

{

    DS1307WriteByte( 0x00, (((rtc.sekunde / 10) << 4) + rtc.sekunde % 10));

    wait_ms(10);   //warte 10ms

    //Minuten

    DS1307WriteByte( 0x01, (((rtc.minute / 10) << 4) + rtc.minute % 10));

    wait_ms(10);

    //Stunden

    DS1307WriteByte( 0x02, (((rtc.stunde / 10) << 4) + rtc.stunde % 10));

    wait_ms(10);

    //Wochentag

    DS1307WriteByte( 0x03, (rtc.wtag & 0x07));

    wait_ms(10);

    //Tag

    DS1307WriteByte( 0x04, (((rtc.tag / 10) << 4) + rtc.tag % 10));

    wait_ms(10);

    //Monat

    DS1307WriteByte( 0x05, (((rtc.monat / 10) << 4) + rtc.monat % 10));

    wait_ms(10);

    //Jahr

    DS1307WriteByte( 0x06, (((rtc.jahr / 10) << 4) + rtc.jahr % 10));

    wait_ms(10);

}

void DS1307WriteByte (  unsigned char RTC_Adresse, unsigned char Value )

{

    I2CSendAddr( DS1307_ADDR , WRITE );

    if( I2CCheckError() > 0 ){

        I2CSendStop();

        //Fehler

        return;

    }

    I2CSendByte( RTC_Adresse );

    I2CSendByte( Value );

    I2CSendStop();

}

unsigned char DS1307ReadByte ( unsigned char RTC_Adresse )

{

    I2CSendAddr( DS1307_ADDR , WRITE );

    if( I2CCheckError() > 0 ){

        I2CSendStop();

        //Fehler

        return 0;

    }

    I2CSendByte( RTC_Adresse );

    I2CSendAddr( DS1307_ADDR, READ );

    temp = I2CGetLastByte();

    I2CSendStop();

    return temp;    

}