DS1302.doc

#include <>
sbit DS1302_data=P2^5;
sbit DS1302_cs=P2^7;
sbit DS1302_clk=P2^6;
unsigned char display_buffer[6];
//延时
void dly()
{
unsigned int i,j;
for(i=0;i<200;i++)
for(j=0;j<200;j++);
}
//短延时
void short_dly()
{
unsigned int i;
for(i=0;i<5;i++);
}
//长延时
void long_dly()
{
unsigned int i;
for(i=0;i<25;i++);
}
//向DS1302写入一个字节子程序
void write(unsigned char DS1302_temp)
{
unsigned char i,temp;
long_dly();
temp=DS1302_temp;
for(i=0;i<8;i++)
{
DS1302_data=temp&0x01;
short_dly();
DS1302_clk=1;
short_dly();
DS1302_clk=0;
temp=temp>>1;
}
}
//从DS1302读取一个字节子程序
unsigned char read(void)
{
unsigned char i,temp;
long_dly();
temp=0;
for(i=0;i<8;i++)
{
temp=temp>>1;
if(DS1302_data==1)
temp=temp+0x80;
DS1302_clk=1;
short_dly();
DS1302_clk=0;
short_dly();
}
return temp;
}
void main()
{
unsigned char i;
DS1302_cs=0;
while(1)
{
DS1302_clk=0;
short_dly();
DS1302_cs=1;
write(0x81);
DS1302_data=1;
i=read();
DS1302_cs= 0;