• 問題描述
  通過 uint16_t ConvData[8]保存DMA搬運的ADC轉(zhuǎn)換數(shù)值，但是這個數(shù)組數(shù)值的順序總是和ADC不是順序?qū)?yīng)的。比如用7個通道的ADC，當設(shè)置ADC_InitStructure.ADC_ScanDirection = ADC_ScanDirection_Backward，是對應(yīng)順序是：0->0,1->7,2->6…7->1 ； 當設(shè)置ADC_InitStructure.ADC_ScanDirection = ADC_ScanDirection_Upward，是對應(yīng)順序是：0->7,1->0,2->1…7->6 。

• 問題原因
  F0的ADC在使用之前需要校準。這個7位的校準值也是放在ADC_DR中的，它也會觸發(fā)DMA請求。
  可以參照F0的ADC-DMA例程，先做ADC校準、然后再設(shè)置DMA，再使能ADC的DMA。

/*********************************************************************************************************/

• 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恢復默認設(shè)置

• 
  

• ? ? ADC_StructInit(&ADC_InitStructure); //初始化ADC結(jié)構(gòu)

• 
  

• ? ? ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b; //12位精度

• ? ? ADC_InitStructure.ADC_ContinuousConvMode = ENABLE; //規(guī)定模式裝換工作在連續(xù)模式

• ? ? ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;

• ? ? ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; //數(shù)據(jù)對其為右對齊

• ? ? ADC_InitStructure.ADC_ScanDirection = ADC_ScanDirection_Upward; // ADC_ScanDirection_Backward; //ADC的掃描方向

• ? ? 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 */

• 
  

• ? ? //設(shè)置DMA要在校準ADC之后

• ? ? DMA_DeInit(DMA1_Channel1); /* DMA1 Channel1 Config */

• ? ? DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t) 0x40012440; //ADC1->DR; //外設(shè)地址

• ? ? DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t) RegularConvData_Tab; //內(nèi)存地址

• ? ? DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC; //外設(shè)作為數(shù)據(jù)傳輸?shù)膩碓?/p>

• ? ? DMA_InitStructure.DMA_BufferSize = 8; //

• ? ? DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; //外設(shè)地址寄存器不變

• ? ? DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; //內(nèi)存地址寄存器不變

• ? ? DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord; //數(shù)據(jù)寬度為16位

• ? ? DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord; //數(shù)據(jù)寬度為16位

• ? ? DMA_InitStructure.DMA_Mode = DMA_Mode_Circular; //DMA_Mode_Circular;

• ? ? DMA_InitStructure.DMA_Priority = DMA_Priority_High; //DMA_Priority設(shè)定DMA通道x的軟件優(yōu)先級

• ? ? DMA_InitStructure.DMA_M2M = DMA_M2M_Disable; //DMA通道x沒有設(shè)置為內(nèi)存到內(nèi)存?zhèn)鬏?/p>

• ? ? 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 */

• 
  

• }

/************************************ END ***********************************************/