源码：
u32 adc_data;                                                                                                                  
void  Adc_Init(void)
{   
  GPIO_InitTypeDef  GPIO_InitStructure;
        ADC_CommonInitTypeDef ADC_CommonInitStructure;
        ADC_InitTypeDef       ADC_InitStructure;
        NVIC_InitTypeDef NVIC_InitStructure;
       
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);//ê1ÄüGPIOAê±Öó
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE); //ê1ÄüADC1ê±Öó

  //Ïè3õê¼»ˉADC1í¨μà5 IO¿ú
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;//PA5 í¨μà5
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;//Ä￡Äaêäèë
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL ;//2»′øéÏÏÂà-
  GPIO_Init(GPIOA, &GPIO_InitStructure);//3õê¼»ˉ  

        RCC_APB2PeriphResetCmd(RCC_APB2Periph_ADC1,ENABLE);          //ADC1¸′λ
        RCC_APB2PeriphResetCmd(RCC_APB2Periph_ADC1,DISABLE);        //¸′λ½áêø         

       
  ADC_CommonInitStructure.ADC_Mode = ADC_Mode_Independent;//¶àá￠Ä￡ê½
  ADC_CommonInitStructure.ADC_TwoSamplingDelay = ADC_TwoSamplingDelay_5Cycles;//ὸö2éÑù½×¶ÎÖ®¼äμÄÑó3ù5¸öê±Öó
  ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_1; //DMAê§Äü
  ADC_CommonInitStructure.ADC_Prescaler = ADC_Prescaler_Div4;//Ô¤·ÖÆμ4·ÖÆμ¡￡ADCCLK=PCLK2/4=84/4=21Mhz,ADCê±Öó×îoÃ2»òa3¬1y36Mhz
  ADC_CommonInit(&ADC_CommonInitStructure);//3õê¼»ˉ
       
  ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;//12λÄ￡ê½
  ADC_InitStructure.ADC_ScanConvMode = DISABLE;//·Çé¨ÃèÄ￡ê½       
  ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;//¿aÆôá¬Dø×a»»
  ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;//½ûÖ1′￥·￠¼ì2a￡¬ê1óÃèí¼t′￥·￠
  ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;//óò¶ÔÆë       
  ADC_InitStructure.ADC_NbrOfConversion = 1;//1¸ö×a»»Ôú1æÔòDòáDÖD ò2¾íêÇÖ»×a»»1æÔòDòáD1
  ADC_Init(ADC1, &ADC_InitStructure);//ADC3õê¼»ˉ
       
        ADC_ITConfig(ADC1,ADC_IT_EOC,ENABLE);//ADCÖD¶Ï¿aÆô
        ADC_Cmd(ADC1, ENABLE);//¿aÆôAD×a»»Æ÷       
        ADC_DMACmd(ADC1,ENABLE);//¿aÆôADCμÄDMA
  NVIC_InitStructure.NVIC_IRQChannel = ADC_IRQn;
        NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=1;//ÇàÕ¼óÅÏ輶3
        NVIC_InitStructure.NVIC_IRQChannelSubPriority =0;                //×óóÅÏ輶3
        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;                        //IRQí¨μàê1Äü
        NVIC_Init(&NVIC_InitStructure);        //¸ù¾YÖ¸¶¨μÄ2Îêy3õê¼»ˉVIC¼Ä′æÆ÷
       
        ADC_RegularChannelConfig(ADC1, 4, 1, ADC_SampleTime_480Cycles);
}       
void ADC_IRQHandler(void)
{   
        if(ADC_GetITStatus(ADC1,ADC_IT_EOC)==SET)
  {
                usart4.printf("the orginal data:%d ",ADC_GetConversionValue(ADC1));   
                MYDMA_Enable(DMA2_Stream0,32);                /*??DMA*/        
    usart4.printf("the dma data:%d ",adc_data);
               

                ADC_ClearITPendingBit(ADC1, ADC_IT_EOC);      //????????
                //usart4.printf("flag ");
  }       
}
/////////////////////////////////////////////////////////////////////////////////////////////
#include "..includedma.h"       
#include "..includeusart.h"       
#include "delay.h"                 
// streamxêy¾Yá÷ chxí¨μàÑ¡Ôñ paríaéèμØÖ· mar′æ′￠Æ÷μØÖ· ndtrêy¾Y′«êäá¿
void MYDMA_Config(DMA_Stream_TypeDef *DMA_Streamx,u32 chx,u32 par,u32 mar,u16 ndtr)
{

        DMA_InitTypeDef  DMA_InitStructure;
        NVIC_InitTypeDef NVIC_InitStructure;
        if((u32)DMA_Streamx>(u32)DMA2)//????stream???DMA2??DMA1
        {
          RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2,ENABLE);//DMA2????
               
        }else
        {
          RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1,ENABLE);//DMA1????
        }
  DMA_DeInit(DMA_Streamx);
       
        while (DMA_GetCmdStatus(DMA_Streamx) != DISABLE){}//??DMA???
       
  /* ?? DMA Stream */
  DMA_InitStructure.DMA_Channel = chx;  //????
  DMA_InitStructure.DMA_PeripheralBaseAddr = par;//DMA????
  DMA_InitStructure.DMA_Memory0BaseAddr = mar;//DMA ???0??
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;//????????
  DMA_InitStructure.DMA_BufferSize = ndtr;//?????
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;//???????
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;//???????
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;//??????:8?
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;//???????:8?
  DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;// ??????
  DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;//?????
  DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;         
  DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full;
  DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;//?????????
  DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;//????????
  DMA_Init(DMA_Streamx, &DMA_InitStructure);//???DMA Stream
               
        DMA_ITConfig(DMA2_Stream0,DMA_IT_TC, ENABLE);
        NVIC_InitStructure.NVIC_IRQChannel = DMA2_Stream0_IRQn;
        NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=1;//ÇàÕ¼óÅÏ輶3
        NVIC_InitStructure.NVIC_IRQChannelSubPriority =0;                //×óóÅÏ輶3
        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;                        //IRQí¨μàê1Äü
        NVIC_Init(&NVIC_InitStructure);       

}
//????DMA??
//DMA_StreamxMA???,DMA1_Stream0~7/DMA2_Stream0~7
//ndtr:?????  
void MYDMA_Enable(DMA_Stream_TypeDef *DMA_Streamx,u16 ndtr)
{

        DMA_Cmd(DMA_Streamx, DISABLE);                      //??DMA??
       
        while (DMA_GetCmdStatus(DMA_Streamx) != DISABLE){}        //??DMA?????  
               
        DMA_SetCurrDataCounter(DMA_Streamx,ndtr);          //?????  
        DMA_Cmd(DMA_Streamx, ENABLE);  
                 //??DMA??
}       
void DMA2_Stream0_IRQHandler(void)
{
        usart4.printf("flag ");
        if(DMA_GetFlagStatus(DMA2_Stream0,DMA_FLAG_TCIF0)!=RESET)//μè′yDMA2_Steam7′«êäíê3é
        {
               
               
                DMA_ClearFlag(DMA2_Stream0,DMA_FLAG_TCIF0);//Çå3yDMA2_Steam7′«êäíê3é±êÖ¾
        }       
}


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