ds1302.c

avr系列单片机访问ds1302的驱动程序

#include "main.h"

void ds1302_init(void)
{
   DS1302_CLK_DIR_OUT;
   DS1302_RST_DIR_OUT;
   DS1302_IO_DIR_OUT;
}

void ds1302_reset(void)
{
   DS1302_CLK_0;
   nop();
   DS1302_RST_0;
   nop();
   DS1302_RST_1;
   nop();
}

void ds1302_write_byte(unsigned char data)
{ 
    unsigned char i;
	for(i=0;i<8;i++)
	{
	   DS1302_CLK_0;
	   nop();
	   if(data&0x01)
	   DS1302_IO_1;
	   else
	   DS1302_IO_0;
	   nop();
	   DS1302_CLK_1;
	   nop();
	   data>>=1;
	   
	}
}

unsigned char ds1302_read_byte(void)
{
    unsigned char i,data;
	data=0;
	
     
	for (i=0;i<8;i++)
	{
	  DS1302_CLK_0;
	  nop();
	  data>>=1;
	  if (DS1302_IO_IN) 
	  data|=0x80;
	  nop();
	  DS1302_CLK_1;
	  nop();
	}
	return data;
}

void ds1302_write(unsigned char reg,unsigned char data)
{    
     DS1302_IO_DIR_OUT;
	 ds1302_reset();
     ds1302_write_byte(reg);
	 ds1302_write_byte(data);
	
	 DS1302_CLK_0;
     nop();
	 DS1302_RST_0;
	 nop();
}

unsigned char ds1302_read(unsigned char reg)
{   
      unsigned char data;
      DS1302_IO_DIR_OUT;
	  ds1302_reset();
	  ds1302_write_byte(reg);
	  DS1302_IO_DIR_IN;
	  data=ds1302_read_byte();
	  DS1302_CLK_0;
      nop();
	  DS1302_RST_0;
	  nop();
	  
	  
	  return data;
	  
}

void gettime(unsigned char *nowtime)
{
   unsigned char i;
    DS1302_IO_DIR_OUT;
    ds1302_reset();
    ds1302_write_byte(0xbf); 
    DS1302_IO_DIR_IN;
	for(i=0;i<7;i++)
	{
	 nowtime[i]=ds1302_read_byte();
	}
	  DS1302_CLK_0;
      nop();
      DS1302_RST_0;
	  nop();
	  
}

void settime(unsigned char *settime)
{ 
   unsigned char i;
   ds1302_write(0x8e,0);
   ds1302_reset();
   ds1302_write_byte(0xbe);
   for(i=0;i<7;i++)
   {
     ds1302_write_byte(settime[i]);
	
   }
     ds1302_write_byte(0);
	 DS1302_CLK_0;
     nop();
	 DS1302_RST_0;
	 nop();
}