stm32f030ADC单次单通道采样

void adc1_dma_init(void)
{
    ADC_InitTypeDef     ADC_InitStruct;
 // DMA_InitTypeDef     DMA_InitStruct;
    GPIO_InitTypeDef    GPIO_InitStruct;
    
    ADC_DeInit(ADC1);
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);
//    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1 , ENABLE);
    //RCC_ADCCLKConfig(RCC_ADCCLK_PCLK_Div4);
    
    GPIO_InitStruct.GPIO_Pin = GPIO_Pin_3|GPIO_Pin_4|GPIO_Pin_5|GPIO_Pin_1;
  //GPIO_InitStruct.GPIO_Pin = GPIO_Pin_1;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AN;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL ;
  GPIO_Init(GPIOA, &GPIO_InitStruct);

    ADC_DeInit(ADC1); 
    ADC_DMACmd(ADC1, DISABLE);
    ADC_StructInit(&ADC_InitStruct);
    
    ADC_InitStruct.ADC_Resolution = ADC_Resolution_12b;
  ADC_InitStruct.ADC_ContinuousConvMode = DISABLE;
    ADC_InitStruct.ADC_ExternalTrigConv = ADC_ExternalTrigConv_T1_TRGO;
  ADC_InitStruct.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
  ADC_InitStruct.ADC_DataAlign = ADC_DataAlign_Right;
  ADC_InitStruct.ADC_ScanDirection = ADC_ScanDirection_Backward;
  ADC_Init(ADC1, &ADC_InitStruct); 
    
    
     ADC_ChannelConfig(ADC1, ADC_Channel_1, ADC_SampleTime_1_5Cycles);
//     ADC_ChannelConfig(ADC1, ADC_Channel_3, ADC_SampleTime_55_5Cycles);
//     ADC_ChannelConfig(ADC1, ADC_Channel_4, ADC_SampleTime_55_5Cycles);
//     ADC_ChannelConfig(ADC1, ADC_Channel_5, ADC_SampleTime_55_5Cycles);
     
     ADC_GetCalibrationFactor(ADC1);
//   ADC_DMACmd(ADC1, ENABLE);
     
     ADC_Cmd(ADC1, ENABLE);
     while(ADC_GetFlagStatus(ADC1, ADC_FLAG_ADEN)==RESET);
     
     
   ADC_StartOfConversion(ADC1);
     while(ADC_GetFlagStatus(ADC1,ADC_FLAG_EOC)==RESET); 
     
     adc_data=ADC_GetConversionValue(ADC1);
}

void adc_chanlset(uint32_t ADC_Channel)
{
    ADC_ChannelConfig(ADC1,ADC_Channel,ADC_SampleTime_1_5Cycles);
}

int haveadval()
{
     ADC_StartOfConversion(ADC1);
     while(ADC_GetFlagStatus(ADC1,ADC_FLAG_EOC)==RESET); 
     adc_data=ADC_GetConversionValue(ADC1);
     return adc_data;
}