AT91SAM7S64处理器8路A/D转换

     最近在淘宝上淘到了1块AT91SAM7S64最小系统板，经扩展外围电路后，用来做A/D转换比较不错。现将A/D转换的代码贴出来供大家参考交流。

#include <AT91SAM7S64.H> 
#include <stdio.h>                          /* I/O Functions */
void Init_ADC(void)
{
    *AT91C_PMC_PCER = (1 << AT91C_ID_PIOA);// | 
    *AT91C_PMC_PCER=*AT91C_PMC_PCER|(1 << AT91C_ID_ADC);

    *AT91C_ADC_CR=AT91C_ADC_SWRST;
    *AT91C_ADC_MR=(AT91C_ADC_PRESCAL)|(AT91C_ADC_LOWRES_10_BIT);
    *AT91C_ADC_CHER=AT91C_ADC_CH0|AT91C_ADC_CH1|
                    AT91C_ADC_CH2|AT91C_ADC_CH3|
        AT91C_ADC_CH4|AT91C_ADC_CH5|
        AT91C_ADC_CH6|AT91C_ADC_CH7;     
}

void Adc_Start(void)
{
   *AT91C_ADC_CR = AT91C_ADC_START;
}

 

unsigned int ADC_ReadValue(unsigned char CH)
{
   unsigned int value;
   *AT91C_ADC_CR = AT91C_ADC_START;

   switch(CH)
   {   case 0:
           {
             while ((*AT91C_ADC_SR & AT91C_ADC_EOC0) == 0);/* wait for ADC conversion    */  

       value= (unsigned int) *AT91C_ADC_CDR0 & AT91C_ADC_DATA;
    break;
     }
    case 1:
           {
             while ((*AT91C_ADC_SR & AT91C_ADC_EOC1) == 0);/* wait for ADC conversion    */  

       value= (unsigned int) *AT91C_ADC_CDR1 & AT91C_ADC_DATA;
    break;
     }
    case 2:
           {
             while ((*AT91C_ADC_SR & AT91C_ADC_EOC2) == 0);/* wait for ADC conversion    */  

       value= (unsigned int) *AT91C_ADC_CDR2 & AT91C_ADC_DATA;
    break;
     }
    case 3:
           {
             while ((*AT91C_ADC_SR & AT91C_ADC_EOC3) == 0);/* wait for ADC conversion    */  

       value= (unsigned int) *AT91C_ADC_CDR3 & AT91C_ADC_DATA;
    break;
     }
    case 4:
           {
             while ((*AT91C_ADC_SR & AT91C_ADC_EOC4) == 0);/* wait for ADC conversion    */  

       value= (unsigned int) *AT91C_ADC_CDR4 & AT91C_ADC_DATA;
    break;
     }
    case 5:
           {
             while ((*AT91C_ADC_SR & AT91C_ADC_EOC5) == 0);/* wait for ADC conversion    */  

       value= (unsigned int) *AT91C_ADC_CDR5 & AT91C_ADC_DATA;
    break;
     }
    case 6:
           {
             while ((*AT91C_ADC_SR & AT91C_ADC_EOC6) == 0);/* wait for ADC conversion    */  

       value= (unsigned int) *AT91C_ADC_CDR6 & AT91C_ADC_DATA;
    break;
     }
     case 7:
           {
             while ((*AT91C_ADC_SR & AT91C_ADC_EOC7) == 0); /* wait for ADC conversion    */  
       value= (unsigned int) *AT91C_ADC_CDR7 & AT91C_ADC_DATA;
    break;
     }

   }
   return value;
}
附： PCB图，供交流。