望TestCode半夜**叫~~~

2万 · 2007-8-23 02:26

#include "adc.h"

AdcObj::AdcObj(void)
{
  Init();
}

/*----------------------------------------------------
R0 = 10K, R1 = 51K, Vref = 2.50V
公式：Vx = Vref * (R0 + R1) / R0

     V0 =2.5*(61/10)=15.25V
     V1 =2.5*(61/10)=15.25V
     V23=2.5*(85/10)=21.25V
     Ak = Vx / 1024
-----------------------------------------------------*/
void AdcObj::Init(void)
{
unsigned char i;
    AdcChNum = 0;
    ADCSRA = 0x00;
    ADMUX  = 0;//选择外部2.50为基准
    ACSR = (1 << ACD);//关闭模拟比较器
    SetAdcChNum(AdcChNum);//设置新通道
    for (i = 0; i < 4; i ++) {
        AdcVal = 0;
        AdcCount = 0;
    }
    AdcSum[1] = 0;
    AdcMax[1] = 0;
    AdcMin[1] = 0x1ff;//9位ADC

    AdcSum[2] = 0;
    AdcMax[2] = 0;
    AdcMin[2] = 0x3ff;//10位ADC

    AdcSum[3] = 0;
    AdcMax[3] = 0;
    AdcMin[3] = 0x3ff;//10位ADC
/*----------------------------------------------------
R0 = 10K, R1 = 51K, Vref = 2.50V, Vk = 10, N = 9, 10
公式：Vx = Vref * (R0 + R1) / R0
    Ak = Vx * / 2 ^ n
    Ak0 = 15250 / 512   (N = 9)
        = 30500 / 1024
    Ak1 = 15250 / 1024
    Ak2 = 21250 / 1024
    Ak3 = 21250 / 1024
-----------------------------------------------------*/

    ADCSRA = (1 << ADEN) | (1 << ADSC) | (1 << ADIE) | (1 << ADPS2) | (1 << ADPS1);//64分频,启动AD转换
}

inline
unsigned char AdcObj::GetAdcChNum(unsigned char ChNum)
{
__root __flash  static const unsigned char AdcChNumTab[4] =
{//ADC通道变换表
    0x09,//0b00001001,//差分测试,*10,ADC1-ADC0
    0x09,//0b00001001,//差分测试,*10,ADC1-ADC0
    0x02,//0b00000010,//单端测试,*1,ADC2
    0x00//0b00000000,//单端测试,*1,ADC0
//    0x03//0b00000011,//电压,单端测试,*1,ADC3
};
    return AdcChNumTab[ChNum & 0x03];//返回ADC通道变换号
}

inline
void AdcObj::SetAdcChNum(unsigned char ChNum)//设置ADC通道变换号
{
//    ADMUX = (1 << REFS1) | (1 << REFS0) | GetAdcChNum(ChNum);//选择内部2.56为基准
    ADMUX = (0 << REFS1) | (1 << REFS0) | GetAdcChNum(ChNum);//选择外部2.50为基准
}

void AdcObj::Exec(void)
{
//volatile
unsigned int AdcResult;
//volatile
unsigned long val;
    AdcResult = ADC & 0x3ff;//取ADC转换电压，并保存
    SetAdcChNum(AdcChNum + 1);//设置新通道
    if (AdcChNum > 0)
    {
/*-----------------------------------------------------------
  求累加和
------------------------------------------------------------*/
        AdcSum[AdcChNum] += AdcResult;//存累加和
/*-----------------------------------------------------------
  求最大值
------------------------------------------------------------*/
        if (AdcResult > AdcMax[AdcChNum])
        {
            AdcMax[AdcChNum] = AdcResult;//最大值
        }
/*-----------------------------------------------------------
  求最小值
------------------------------------------------------------*/
        if (AdcResult <= AdcMin[AdcChNum])
        {
            AdcMin[AdcChNum] = AdcResult;//存最小值
        }
        AdcCount[AdcChNum] ++;
        if (AdcCount[AdcChNum] >= 18)//每点测试18次，滤波
        {
/*-----------------------------------------------------------
  求平均值
------------------------------------------------------------*/
/*----------------------------------------------------
     V0 =2.5*(61/10)=15.25V
     V1 =2.5*(61/10)=15.25V
     V23=2.5*(85/10)=21.25V
-----------------------------------------------------*/
            val = AdcSum[AdcChNum] - AdcMax[AdcChNum] - AdcMin[AdcChNum];
            val *= AdcAkVal[AdcChNum];
            val >>= 14;//18中取16后除以1024
            AdcVal[AdcChNum] = val;
/*-----------------------------------------------------------
  初始化
------------------------------------------------------------*/
            AdcSum[AdcChNum] = 0;
            AdcMax[AdcChNum] = 0;
            if (AdcChNum == 1)
            {
                AdcMin[AdcChNum] = 0x1ff;//9位ADC
            }
            else
            {
                AdcMin[AdcChNum] = 0x3ff;//10位ADC
            }
            AdcCount[AdcChNum] = 0;
    }
    AdcChNum ++;//准备下个通道
    AdcChNum &= 3;
    ADCSRA = (1 << ADEN) | (1 << ADSC) | (1 << ADIE) | (1 << ADPS2) | (1 << ADPS1);//64分频
}