求助DS2438芯片测量电池容量是0的问题

只看该作者 · 2015-4-15 14:26

本帖最后由 hlln20100410 于 2015-4-17 15:34 编辑

使用DS2438芯片测量电池的电压、温度、电流，都没有问题;
可最终要测量的是电池的剩余容量，看芯片手册进行函数操作，可是读出来的ICA  CCA DCA寄存器都是0，不知哪位前辈用过该芯片，小弟虚心求教
程序和电路如下，读取电池剩余容量时只读了第四个字节ICA寄存器，仿真看值是0；
/******************************************************************
******函数名称：读取端口电压值
*****返回值：无
*****作者：
*****时间：2015年3月31日10:55:54
*******************************************************************/
unsigned int DS2438_Read_Voltage(void)
{
      unsigned char temp_V[9],i;
      float Voltage;
   i= Reset_DS2438();
      while(i==0x80);

write_byte(0xcc);
write_byte(0xB4); //0xB4
      delay_ms(10);
i= Reset_DS2438();
      while(i==0x80);

write_byte(0xcc);
write_byte(0xB8); //0xB8
write_byte(0x00);
i= Reset_DS2438();
      while(i==0x80);

write_byte(0xCC);
write_byte(0XBE); //0xBE
write_byte(0x00);
for(i=0;i<9;i++)
   {
temp_V=read_byte();
   }
      Voltage=((temp_V[4]&0x03)*256+temp_V[3])*0.01;
      return(Voltage);
}
/******************************************************************
******读取当前电池温度
*****返回值：无
*****作者：
*****时间：2015年3月31日10:55:54
*******************************************************************/
unsigned int Read_Temperature(void)
{
      unsigned char g[9];
      unsigned char i,j;
      unsigned int  u;

      float temperature;
      union
         {
            unsigned int  temp16;
            struct
            {
                  unsigned char  bytel;
                  unsigned char  byteh;
               };
         }word;
      i= Reset_DS2438() ;
      while(i==0x80);

      write_byte(0xCC); //Skip ROM
      write_byte(0x44); // Start Conversion
      delay_ms(30);

      i= Reset_DS2438() ;
      while(i==0x80);
      write_byte(0xCC); //Skip ROM
      write_byte(0xB4); // Start Conversion
      i= Reset_DS2438() ;
      while(i==0x80);

      write_byte(0xCC); // Skip ROM
      write_byte(0xB8); //READ SCRATCHPAD
      write_byte(0x00); //READ 0TH PAGE
      i=Reset_DS2438() ;
      while(i==0x80);
      write_byte(0xCC); // Skip ROM
      write_byte(0xBE); // Read Scratch Pad
      write_byte(0x00);
      for(j=0;j<9;j++)
      {
         g[j]=read_byte();
      }
      word.byteh=g[2];
      word.bytel=g[1];
      u=word.temp16>>3;
      temperature=u*0.03125;
      return (temperature);
}

/******************************************************************
******读取当前电池读电流
*****返回值：CURENT y=(-0.2441X+250)/500;计算电流
*****作者：
*****时间：2015年4月11日16:12:13
*******************************************************************/
unsigned int DS2438_Read_Current(void)
{
      unsigned char temp_C[9];
      unsigned int i,aac;
      float Current,temp_1;
      initcommand();
      write_byte(0xCC);
      write_byte(0XB4);
      delay_ms(200);
      i= Reset_DS2438();
      while(i==0x80);
      write_byte(0xCC);
      write_byte(0XB8); //0xB8
      write_byte(0x00);
      delay_ms(200);
      i= Reset_DS2438();
      while(i==0x80);
      write_byte(0XCC);
      write_byte(0XBE); //0xBE
      write_byte(0x00);
      delay_ms(200);
for(i=0;i<9;i++)
   {
         temp_C=read_byte();
   }
      temp_C[6]= temp_C[6]&0x03;
      aac=temp_C[6]<<8;
      aac=aac+temp_C[5];
      Current=(-0.2441*aac+250)/500.0;//单位mA V=-0.2441X+250;X是二进制数据
      return( Current);
}
/////////////////////////////////////////////////////////////////////////////////////////////
//读电池的当前剩余容量
unsigned char Read_ICAcurrent(void)
{  // unsigned char a[9];
unsigned char d[9];
unsigned char i,j;
float p;

initcommand();
i= Reset_DS2438() ;
while(i==0x80);

//write_byte(0xCC); // Skip ROM
// write_byte(0x4E);
//write_byte(0x00);
//write_byte(0x0F);
//i= Reset_DS2438() ;
//while(i==0x80);

write_byte(0xCC); // Skip ROM
write_byte(0xB8);
write_byte(0x01);
i= Reset_DS2438() ;
while(i==0x80);
write_byte(0xCC); // Skip ROM
write_byte(0xBE);
write_byte(0x01);

for(j=0;j<9;j++)
      {
         d[j]=read_byte();
      }
   p =d[4]/(2048*0.5);
      return (p);
}