Posted on April 01, 2017 at 20:22Hi,
Trying to do a ADC continuous scan with 4 sequential channels using DMA, ending up with one single DMA Transfer Complete Interrupt, though I am clearing the TC interrupt. The single transfer has the correct ADC result for all the 4 channels, but it fires just once alone. Read the Reference manual a few times, but cant find what I am indeed missing to get the Continuous Conversion working. Aargh! Obviously, I am missing something .. Is someone kind enough to lend a set of eyeballs, to find what I am missing ?
Thanks!
The output what I get:
DMA1_TC
::0 1653 0 1
extern char adcstr[50];
uint16_t ADCVal[4] = {0, 0, 0, 0};
void DMA1_Channel1_IRQHandler(void)
{
if (DMA_GetITStatus(DMA1_IT_TC1)) {
putstr(USART1, 'DMA1_TC\r');
sprintf((char*)adcstr, '::%d %d %d %d\r', ADCVal[0], ADCVal[1], ADCVal[2], ADCVal[3]);
putstr(USART1, adcstr);
DMA_ClearITPendingBit(DMA1_IT_TC1);
}
if (DMA_GetITStatus(DMA1_IT_TE1)) {
putstr(USART1, 'DMA1_TE\r');
DMA_ClearITPendingBit(DMA1_IT_TE1);
}
}
void adc_dmascan_init(void)
{
__IO uint32_t cal_factor = 0;
ADC_InitTypeDef adci;
ADC_CommonInitTypeDef adcc;
DMA_InitTypeDef dma;
/* ADC and GPIO clk config */
RCC_ADCCLKConfig(RCC_ADC12PLLCLK_Div2); /* ADC12 clock = PLLCLK/2 */
__ADC12_CLK_ENABLE(); /* enable ADC1 clock */
__ADC_VREG_ENABLE(ADC1); /* enable ADC voltage regulator */
delay(10); /* wait 10uS */
__ADC_CALMODE_SINGLE(ADC1); /* calibrate single ended */
__ADC_CALIBRATE(ADC1);
while (!__ADC_CAL_DONE(ADC1));
cal_factor = __ADC_CAL_FACTOR(ADC1);
/* setup DMA Ch:1 */
__DMA1_CLK_ENABLE();
dma.DMA_DIR = DMA_DIR_PeripheralSRC;
dma.DMA_Mode = DMA_Mode_Circular;
dma.DMA_PeripheralBaseAddr = (uint32_t)&ADC1->DR;
dma.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
dma.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
dma.DMA_MemoryBaseAddr = (uint32_t)&ADCVal;
dma.DMA_BufferSize = 4;
dma.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
dma.DMA_MemoryInc = DMA_MemoryInc_Enable;
dma.DMA_Mode = DMA_Mode_Normal;
DMA_Init(DMA1_Channel1, &dma);
DMA_ITConfig(DMA1_Channel1, DMA_IT_TC, ENABLE);
DMA_ITConfig(DMA1_Channel1, DMA_IT_TE, ENABLE);
NVIC_EnableIRQ(DMA1_Channel1_IRQn);
/* ADC Common Init */
adcc.ADC_Mode = ADC_Mode_Independent;
adcc.ADC_DMAAccessMode = ADC_DMAAccessMode_Disabled;
adcc.ADC_DMAMode = ADC_DMAMode_Circular;
adcc.ADC_Clock = ADC_Clock_AsynClkMode;
adcc.ADC_TwoSamplingDelay = 0;
ADC_CommonInit(ADC1, &adcc);
/* ADC Init */
ADC_StructInit(&adci);
adci.ADC_Resolution = ADC_Resolution_12b;
adci.ADC_ContinuousConvMode = ADC_ContinuousConvMode_Enable;
adci.ADC_DataAlign = ADC_DataAlign_Right;
adci.ADC_NbrOfRegChannel = 4;
adci.ADC_ExternalTrigConvEvent = ADC_ExternalTrigConvEvent_0;
adci.ADC_ExternalTrigEventEdge = ADC_ExternalTrigEventEdge_None;
adci.ADC_OverrunMode = ADC_OverrunMode_Disable;
adci.ADC_AutoInjMode = ADC_AutoInjec_Disable;
ADC_Init(ADC1, &adci);
/* Select channels to read */
ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 1, ADC_SampleTime_181Cycles5);
ADC_RegularChannelConfig(ADC1, ADC_Channel_2, 2, ADC_SampleTime_181Cycles5);
ADC_RegularChannelConfig(ADC1, ADC_Channel_3, 3, ADC_SampleTime_181Cycles5);
ADC_RegularChannelConfig(ADC1, ADC_Channel_4, 4, ADC_SampleTime_181Cycles5);
ADC_DMAConfig(ADC1, ADC_DMAMode_Circular);
ADC_DMACmd(ADC1, ENABLE);
ADC_Cmd(ADC1, ENABLE);
while (!ADC_GetFlagStatus(ADC1, ADC_FLAG_RDY));
DMA_Cmd(DMA1_Channel1, ENABLE);
ADC_StartConversion(ADC1);
}
