ds1302时钟-AVR程序代码

#include 

#include "DS1302.h"

#include 

void ds1302_init(void)

{

    PORTX=0x00;

    DDRX=0x07;

}

void write_ds1302_byte(unsigned char dat)

{

    unsigned char i;

    for(i=0;i<8;i++)

    {

    SCK=0;

    IO_out=dat&0x01;

    dat=dat>>1; 

    SCK=1;

    }

}

void write_ds1302(unsigned char add,unsigned char dat)

{

    RST=1;

    delay_us(1);

    write_ds1302_byte(add);

    write_ds1302_byte(dat);    

    RST=0;

    delay_us(2); 

    IO_out=0;  

    SCK=0;     

}

unsigned char read_ds1302(unsigned char add)

{

    unsigned char i,value=0;

    RST=1; 

    write_ds1302_byte(add);

    IO_setting=0;

    for(i=0;i<8;i++)

    {

    value=value>>1;

    SCK=0;

    SCK=0; //必须给两次！！

    if(IO_in) value=value|0x80;

    SCK=1;    

    }

    IO_setting=1;

    SCK=0;

    RST=0;

    delay_us(2);

    IO_out=0;

    return value;    

}

void set_rtc(unsigned char* time_data)

{

    unsigned char i,j,write_add;

    for(i=0;i<7;i++)

    {

        j=time_data[i]/10;

        time_data[i]=time_data[i];

        time_data[i]=time_data[i]+j*16;

    }    

    write_ds1302(0x8e,0x00);//去除写保护

    for(i=0,write_add=0x8c;i<7;i++,write_add-=2)

        write_ds1302(write_add,time_data[i]);

    write_ds1302(0x8e,0x80);        

}

void read_rtc(unsigned char* time_data)

{

    unsigned char i,j,read_add;

    write_ds1302(0x8e,0x00);

    for(i=0,read_add=0x8d;i<7;i++,read_add-=2)

        time_data[i]=read_ds1302(read_add);

    for(i=0;i<7;i++)

    {

        j=time_data[i]/16;

        time_data[i]%=16;

        time_data[i]+=j*10;

    }  

    write_ds1302(0x8e,0x80);

}