时钟芯片DS1302相关资料

在最初接触单片机的时候，很多人都想做一个时钟，有些方案是直接用单片机进行计算的，这个我做过；还有一种方案是使用时钟芯片，而在选择时钟芯片的时候，很多人的眼光都会聚焦在DS1302这个芯片上：

DS1302 是美国DALLAS公司推出的一种高性能、低功耗、带RAM的实时时钟电路，它可以对年、月、日、周日、时、分、秒进行计时，具有闰年补偿功能，工作电压为2.5V～5.5V。采用三线接口与CPU进行同步通信，并可采用突发方式一次传送多个字节的时钟信号或RAM数据。DS1302内部有一个31×8的用于临时性存放数据的RAM寄存器。DS1302是DS1202的升级产品，与DS1202兼容，但增加了主电源/后背电源双电源引脚，同时提供了对后背电源进行涓细电流充电的能力。

我当时在使用DS1302时，也曾收集了一些资料，附件是这块芯片的英文和中文资料，可下载参考。

同时，也贴上这个芯片与51单片机的底层通信代码（代码是本人网上搜集并稍作修改的），希望对大家有用。

sbit DS1302_clk=0xb7;
sbit DS1302_data=0xb6;
sbit DS1302_cs=0xb5;

unsigned char year,month,date,hour,minute,second,week;

void short_ds1302_delay()
{
  unsigned char i;
  for(i=0;i<5;i++);
}

void long_ds1302_delay()
{
  unsigned char i;
  for(i=0;i<25;i++);
}

void DS1302_write(unsigned char DS1302_temp)
{
  unsigned char i,temp;
  long_ds1302_delay();
  temp=DS1302_temp;
  for(i=0;i<8;i++)
  {
    DS1302_data=temp&0x01;
 short_ds1302_delay();
 DS1302_clk=1;
 short_ds1302_delay();
 DS1302_clk=0;
 temp=temp>>1;
  }
}

unsigned char DS1302_read(void)
{
  unsigned char i,temp;
  long_ds1302_delay();
  temp=0;
  for(i=0;i<8;i++)
  {
    temp=temp>>1;
 if(DS1302_data==1)
   temp=temp+0x80;
 DS1302_clk=1;
 short_ds1302_delay();
 DS1302_clk=0;
 short_ds1302_delay();
  }
  return temp;
}

/////////写操作设置,当a=0x80时禁止写操作,a=0x00时允许////////////////

void DS1302_write_able(unsigned char a)
{
  DS1302_cs=0;

  DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x8e);
  DS1302_data=1;
  DS1302_write(a);
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;
}

////////////////////ds1302初始化////////////////////////
void DS1302_init()
{
  unsigned char i;
  DS1302_write_able(0x00);   //允许写操作

  DS1302_cs=0;

  DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x81);
  DS1302_data=1;
  i=DS1302_read();
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;
  second=((i>>4)&0x07)*10+(i&0x0f);

  DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x80);
  DS1302_data=1;
  DS1302_write(0x7f&i);
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1; 
  
  DS1302_clk=0;    //充电设置
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x90);
  DS1302_data=1;
  DS1302_write(0xa6);    //允许充电,一个二极管 4k电阻
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;  
   
  DS1302_write_able(0x80);   //禁止写操作
}

void DS1302_readdate()
{
  unsigned char i;
  DS1302_cs=0;

  //读取second
  DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x81);
  DS1302_data=1;
  i=DS1302_read();
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;
  second=((i>>4)&0x07)*10+(i&0x0f);

  //读取分minute
  DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x83);
  DS1302_data=1;
  i=DS1302_read();
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;
  minute=((i>>4)&0x07)*10+(i&0x0f);

  //读取时hour
  DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x85);
  DS1302_data=1;
  i=DS1302_read();
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;
  hour=((i>>4)&0x03)*10+(i&0x0f);

  //读取日date
    DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x87);
  DS1302_data=1;
  i=DS1302_read();
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;
  date=((i>>4)&0x03)*10+(i&0x0f);

  //读取月份month
    DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x89);
  DS1302_data=1;
  i=DS1302_read();
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;
  month=((i>>4)&0x01)*10+(i&0x0f);

  //读取周week
    DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x8b);
  DS1302_data=1;
  i=DS1302_read();
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;
  week=i&0x07;

  //读取年份year
    DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x8d);
  DS1302_data=1;
  i=DS1302_read();
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;
  year=((i>>4)&0x0f)*10+(i&0x0f);
}

void DS1302_writedate()
{

  DS1302_write_able(0x00);
  DS1302_cs=0;

  //写second
  DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x80);
  DS1302_data=1;
  DS1302_write(0x7f&(((second/10)<<4)+(second%10)));
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;

  //minute
  DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x82);
  DS1302_data=1;
  DS1302_write(0x7f&(((minute/10)<<4)+(minute%10)));
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;

  //hour
  DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x84);
  DS1302_data=1;
  DS1302_write(0x3f&(((hour/10)<<4)+(hour%10)));
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;

  //date
    DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x86);
  DS1302_data=1;
  DS1302_write(0x3f&(((date/10)<<4)+(date%10)));
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;

  //month
    DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x88);
  DS1302_data=1;
  DS1302_write(0x1f&(((month/10)<<4)+(month%10)));
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;

  //week
  DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x8a);
  DS1302_data=1;
  DS1302_write(0x07&week);
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;

  //year
    DS1302_clk=0;
  short_ds1302_delay();
  DS1302_cs=1;
  DS1302_write(0x8c);
  DS1302_data=1;
  DS1302_write(((year/10)<<4)+(year%10));
  DS1302_cs=0;
  short_ds1302_delay();
  DS1302_clk=1;

  DS1302_write_able(0x80);
}