ad7715.c

ad7715在avr单片机下的驱动程序

#include<iom128v.h>
#include<math.h>
#include <macros.h>

#include "ad7715.h"
unsigned int ADC_buffer;
unsigned char Ready;

void Channel(unsigned char channel)
{
    DDRB |= 0x06;
	channel &= 0x03;
	if(channel == 0)
	{
	   PORTB &= ~0x06;
	}
	else if(channel == 1)
	{
	    PORTB &= ~0x02;
		PORTB |= 0x04;
	}
	else if(channel == 2)
	{
	    PORTB |= 0x02;
		PORTB &= ~0x04;
	}
	else if(channel == 3)
	{
	    PORTB |= 0x06;
	}
}
void Delayx10ms(unsigned int count)
     {  unsigned int i,j,k;
        for(i=0;i<count;i++)
           for (j=0;j<1950;j++)
               for (k=0;k<10;k++)
               ;
     }
void wrad7715(unsigned char cod)
{    unsigned char i;
     DAT_DIR_OUT;
     for(i=0;i<8;i++)
        { SCLK_0;
		  delay(10);
		  if(cod&0x80)
		  {
		     DAT_1;
		  }
		  else
		  {
		      DAT_0;
		  }
		  delay(10);
          SCLK_1;
		  delay(10);
          cod=cod<<1;
        }
}
unsigned int rddata(void)
{   unsigned char i;
    unsigned int  dat=0;
	DAT_DIR_IN;
    for(i=0;i<16;i++)
        {  dat<<=1;
           SCLK_0;
           delay(10);
           SCLK_1;
		   delay(10);
           if(DAT_IN) dat|=0x0001;
        }
        return(dat);
}

void reset_ad7715(void)
{   unsigned char i;
    DAT_1;
	DAT_DIR_OUT;
    for(i=0;i<0x30;i++)
       {  SCLK_0;
          delay(10);
          SCLK_1;
		  delay(10);
       }
}
void Init_AD7715(void)    //初始化子程序
{  
    DDRE |= 0x04;
    DDRE &= ~0x10;
    reset_ad7715();  //对AD7715复位
    wrad7715(0x10);  //写通信寄存器
    wrad7715(0x64);  //写设置寄存器,设定自校准模式，
                    //时钟选用2.4576MHZ，
                    //数据输出率为50次每秒
   Delayx10ms(10);
   wrad7715(0x28);  //写通信寄存器
}
unsigned long temp=0;
unsigned int max=0,min=0xffff;
unsigned char adc_time=0;
#pragma interrupt_handler ad7715:6
void ad7715(void)
{   unsigned int Adc_temp=0;
    wrad7715(0x38);
    Adc_temp=rddata();
	if(adc_time<10)
     {
    
         temp+=Adc_temp;
         if(Adc_temp>max) max=Adc_temp;
         if(Adc_temp<min) min=Adc_temp;
         adc_time++;
      }
	  else
	  {
	      AD7715_Int_STOP;
      	  temp=temp-max-min;
      	  ADC_buffer = temp/8;
		  Ready=1;
		  adc_time = 0;
		  temp=0;
          max=0;
		  min=0xffff;
	  }
    
	
}

unsigned int Getadc(void)
{    unsigned long temp;
     unsigned int max;
     unsigned int min;
     unsigned char i;
     temp=0;
     min=0xffff;
     max=0x0000;
     i=0;
     Ready=0;
     AD7715_Int_ON;
     while(i<10)
     {
        if(Ready)
          {   Ready=0;
              temp+=ADC_buffer;
              if(ADC_buffer>max) max=ADC_buffer;
              if(ADC_buffer<min) min=ADC_buffer;
              i++;

           }

      }
      AD7715_Int_STOP;
      temp=temp-max-min;
      temp/=8;
      return(temp);
}