STM32F249 ADC using EXTI11 + DMA

[bagasprima]

Posted on December 08, 2015 at 12:08

Hello,

I'm trying to use ADC with EXTI_ I have read many discussions before but still got an issue here. Here's the code I'm using:

static void ADC3_CH13_DMA_Config(void)
{
ADC_InitTypeDef ADC_InitStructure;
ADC_CommonInitTypeDef ADC_CommonInitStructure;
DMA_InitTypeDef DMA_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
/* Enable ADC3, DMA2 and GPIO clocks ****************************************/
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2 | RCC_AHB1Periph_GPIOC, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC3, ENABLE);
/* DMA2 Stream0 channel2 configuration **************************************/
DMA_InitStructure.DMA_Channel = DMA_Channel_2; 
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)ADC3_DR_ADDRESS;
DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)&uhADC3ConvertedValue;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
DMA_InitStructure.DMA_BufferSize = 1;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Disable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable; 
DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
DMA_Init(DMA2_Stream0, &DMA_InitStructure);
DMA_Cmd(DMA2_Stream0, ENABLE);
/* Configure ADC3 Channel13 pin as analog input ******************************/
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL ;
GPIO_Init(GPIOC, &GPIO_InitStructure);
/* ADC Common Init **********************************************************/
ADC_CommonInitStructure.ADC_Mode = ADC_Mode_Independent;
ADC_CommonInitStructure.ADC_Prescaler = ADC_Prescaler_Div2;
ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_Disabled;
ADC_CommonInitStructure.ADC_TwoSamplingDelay = ADC_TwoSamplingDelay_5Cycles;
ADC_CommonInit(&ADC_CommonInitStructure);
/* ADC3 Init ****************************************************************/
ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
ADC_InitStructure.ADC_ScanConvMode = DISABLE;
ADC_InitStructure.ADC_ContinuousConvMode = DISABLE;
ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_RisingFalling;
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_Ext_IT11; 
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
ADC_InitStructure.ADC_NbrOfConversion = 1;
ADC_Init(ADC3, &ADC_InitStructure);
/* ADC3 regular channel13 configuration *************************************/
ADC_RegularChannelConfig(ADC3, ADC_Channel_13, 1, ADC_SampleTime_3Cycles);
/* Enable DMA request after last transfer (Single-ADC mode) */
ADC_DMARequestAfterLastTransferCmd(ADC3, ENABLE);
/* Enable ADC3 DMA */
ADC_DMACmd(ADC3, ENABLE);
/* Enable ADC3 */
ADC_Cmd(ADC3, ENABLE);
}
static void EXTILine11_Config(void)
{
EXTI_InitTypeDef EXTI_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
//PC11 for external trigger
GPIO_StructInit(&GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL ;
GPIO_Init(GPIOC, &GPIO_InitStructure);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOC, EXTI_PinSource11);
//EXTI Configuration Line 11
EXTI_DeInit();
EXTI_StructInit(&EXTI_InitStructure);
EXTI_InitStructure.EXTI_Line = EXTI_Line11;
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Event;
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
EXTI_InitStructure.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStructure);
}

And here's the main program:

int main(void)
{ 
PWM_Config();
GPIO_Config();
EXTILine11_Config();
/*!< At this stage the microcontroller clock setting is already configured, 
this is done through SystemInit() function which is called from startup
file (startup_stm32f429_439xx.s) before to branch to application main.
To reconfigure the default setting of SystemInit() function, refer to
system_stm32f4xx.c file
*/
/* ADC3 configuration *******************************************************/
/* - Enable peripheral clocks */
/* - DMA2_Stream0 channel2 configuration */
/* - Configure ADC Channel13 pin as analog input */
/* - Configure ADC3 Channel13 */
ADC3_CH13_DMA_Config();
/* Start ADC3 Software Conversion */ 
ADC_SoftwareStartConv(ADC3);
while (1)
{
}
}

Those are the ADC functions I'm using, and I've printed the ADC readings as the results. But, it seems that the external trigger function is not working, and the reading stays still. Thanks before.

[Tesla DeLorean]

Posted on December 08, 2015 at 14:06

Got some sequencing issues here. You need to get all the clocks enabled first, so when you program the peripherals there clocks are actually running. Would appear that you configure GPIOC before you enable it's clock, and that's not going to work.

Perhaps you initialize them in code I can't see, impossible to tell with selective editing.

[bagasprima]

Posted on December 08, 2015 at 21:35 The original post was too long to process during our migration. Please click on the provided URL to read the original post. https://st--c.eu10.content.force.com/sfc/dist/version/download/?oid=00Db0000000YtG6&ids=0680X000006I6ii&d=%2Fa%2F0X0000000btx%2FUsD3tLS89mpZs5IMEXKNdRmg.6FfAWcwg40f5NytcZs&asPdf=false