上面这段GetADCResult()是原来的AD采集,没什么变化,看看就行了
GetResult()这个是软件滤波的,10位AD的之前弄滤波总出错,今天刚弄好。
关键在于(unsigned long)(),不加这个就总出错!计算过程中溢出,感觉好像是计算时自动降位了
ulong GetADCResult(uchar ch)
{
ulong AD_result;
ADC_CONTR = ADC_POWER | ADC_SPEEDLL | ch | ADC_START;
_nop_(); //Must wait before inquiry
_nop_();
_nop_();
_nop_();
while (!(ADC_CONTR & ADC_FLAG));//Wait complete flag
ADC_CONTR &= ~ADC_FLAG; //Close ADC
AD_result=ADC_RES*4+ADC_RESL;
return AD_result; //Return ADC result 10bit
}
ulong GetResult(uchar ch) //滤波段
{
ulong AD_result=0,AD_result1=0;
ulong AD_max,AD_min,AD_temp;
char AD_i,AD_o;
for(AD_i=0;AD_i<4;AD_i++)
{
AD_min=AD_max=GetADCResult(ch);
AD_result=0;
for(AD_o=0;AD_o<8;AD_o++)
{
AD_temp=GetADCResult(ch);
if(AD_temp<AD_min){AD_result =(unsigned long)(AD_result + (unsigned long)AD_min); AD_min=AD_temp;}
else
if(AD_temp>AD_max){AD_result =(unsigned long)(AD_result + (unsigned long)AD_max); AD_max=AD_temp;}
else
AD_result =(unsigned long)(AD_result + (unsigned long)AD_temp);
}
AD_result=(unsigned long)(AD_result/8);
AD_result1=AD_result1+ (unsigned long)(AD_result);
}
AD_result1=(unsigned long)(AD_result1/4);
return AD_result; //Return ADC result 10bit
}
方法是基于:去除最大最小值后平均。共采样了33次去掉9个后的结果平均值,我自己做电压表,速度足够!如果嫌慢的话可以把AD_i<4中的这个4改小点或者把这个循环去掉。
