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[操作系统]记STM32F030多通道ADC DMA读取乱序问题

  • 问题描述
    通过 uint16_t ConvData[8]保存DMA搬运的ADC转换数值,但是这个数组数值的顺序总是和ADC不是顺序对应的。比如用7个通道的ADC,当设置ADC_InitStructure.ADC_ScanDirection = ADC_ScanDirection_Backward,是对应顺序是:0->0,1->7,2->6…7->1 ; 当设置ADC_InitStructure.ADC_ScanDirection = ADC_ScanDirection_Upward,是对应顺序是:0->7,1->0,2->1…7->6 。
  • 问题原因
    F0的ADC在使用之前需要校准。这个7位的校准值也是放在ADC_DR中的,它也会触发DMA请求。
    可以参照F0的ADC-DMA例程,先做ADC校准、然后再设置DMA,再使能ADC的DMA。
  • 实例代码
void ADC1_DMA_Init(void){  GPIO_InitTypeDef GPIO_InitStructure;  DMA_InitTypeDef DMA_InitStructure;  ADC_InitTypeDef ADC_InitStructure;  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);  GPIO_InitStructure.GPIO_Pin = 0x00ff;  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;  GPIO_Init(GPIOA, &GPIO_InitStructure);  RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);  ADC_DeInit(ADC1); //ADC恢复默认设置  ADC_StructInit(&ADC_InitStructure); //初始化ADC结构  ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b; //12位精度  ADC_InitStructure.ADC_ContinuousConvMode = ENABLE; //规定模式装换工作在连续模式  ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;  ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; //数据对其为右对齐  ADC_InitStructure.ADC_ScanDirection = ADC_ScanDirection_Upward; // ADC_ScanDirection_Backward; //ADC的扫描方向  ADC_Init(ADC1, &ADC_InitStructure);  ADC_ChannelConfig(ADC1, ADC_Channel_0, ADC_SampleTime_239_5Cycles); /* Convert the ADC1 Channel 11 with 239.5 Cycles as sampling time */  ADC_ChannelConfig(ADC1, ADC_Channel_1, ADC_SampleTime_239_5Cycles); /* Convert the ADC1 Channel 11 with 239.5 Cycles as sampling time */  ADC_ChannelConfig(ADC1, ADC_Channel_2, ADC_SampleTime_239_5Cycles); /* Convert the ADC1 Channel 11 with 239.5 Cycles as sampling time */  ADC_ChannelConfig(ADC1, ADC_Channel_3, ADC_SampleTime_239_5Cycles); /* Convert the ADC1 Channel 11 with 239.5 Cycles as sampling time */  ADC_ChannelConfig(ADC1, ADC_Channel_4, ADC_SampleTime_239_5Cycles); /* Convert the ADC1 Channel 11 with 239.5 Cycles as sampling time */  ADC_ChannelConfig(ADC1, ADC_Channel_5, ADC_SampleTime_239_5Cycles); /* Convert the ADC1 Channel 11 with 239.5 Cycles as sampling time */  ADC_ChannelConfig(ADC1, ADC_Channel_6, ADC_SampleTime_239_5Cycles); /* Convert the ADC1 Channel 11 with 239.5 Cycles as sampling time */  ADC_ChannelConfig(ADC1, ADC_Channel_7, ADC_SampleTime_239_5Cycles); /* Convert the ADC1 Channel 11 with 239.5 Cycles as sampling time */  ADC_GetCalibrationFactor(ADC1); /* ADC Calibration */  ADC_Cmd(ADC1, ENABLE); /* Enable ADCperipheral[PerIdx] */  while (!ADC_GetFlagStatus(ADC1, ADC_FLAG_ADRDY))    ; /* Wait the ADCEN falg */  //设置DMA要在校准ADC之后
  DMA_DeInit(DMA1_Channel1); /* DMA1 Channel1 Config */  DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t) 0x40012440; //ADC1->DR; //外设地址  DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t) RegularConvData_Tab; //内存地址  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC; //外设作为数据传输的来源  DMA_InitStructure.DMA_BufferSize = 8; //  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; //外设地址寄存器不变  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; //内存地址寄存器不变  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord; //数据宽度为16位  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord; //数据宽度为16位  DMA_InitStructure.DMA_Mode = DMA_Mode_Circular; //DMA_Mode_Circular;  DMA_InitStructure.DMA_Priority = DMA_Priority_High; //DMA_Priority设定DMA通道x的软件优先级  DMA_InitStructure.DMA_M2M = DMA_M2M_Disable; //DMA通道x没有设置为内存到内存传输  DMA_Init(DMA1_Channel1, &DMA_InitStructure);  DMA_Cmd(DMA1_Channel1, ENABLE);/* DMA1 Channel1 enable */  DMA_ITConfig(DMA1_Channel1, DMA_IT_TC, ENABLE);  ADC_DMARequestModeConfig(ADC1, ADC_DMAMode_Circular); /* Enable ADC_DMA */  ADC_DMACmd(ADC1, ENABLE);  ADC_StartOfConversion(ADC1); /* ADC1 regular Software Start Conv */}