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Again...ADC with 2 Channel with DMA not working!?

dawnofapril10
Associate II
Posted on October 15, 2015 at 06:03

Hi.I'm a newbie in ST and ARM.I tried to setup 2 Channel ADC with DMA but it's not working.Can somebody guide me?.I think i keep on making mistakes somewhere.Thanks!

/*Preprocessors Directives*/
#include <
stm32f0xx_adc.h
>
#include <
stm32f0xx_gpio.h
>
#include <
stm32f0xx_rcc.h
>
#include <
stm32f0xx_dma.h
>
/*APB memory address*/
#define ADC1_DR_Address 0x40012440
/*Variable declaration - ADC*/
volatile uint16_t ADC1_val[2];
/*Function Prototypes*/
void ADC_GPIO_DMA_CONFIG(void);
#define BLed GPIO_Pin_8;
int main(void)
{
//RCC_ClocksTypeDef RCC_Clocks;
//RCC_GetClocksFreq(&RCC_Clocks); 
//if (SysTick_Config(RCC_Clocks.HCLK_Frequency / 1000)) 
//while(1);
ADC_GPIO_DMA_CONFIG();
while(1)
{
if(ADC1_val[0] > 2000)
{
GPIOC->BRR = BLed;
}
else
{
GPIOC->BSRR = BLed;
}
}
}
/*Initialise Configurations for GPIO, ADC and DMA*/
void ADC_GPIO_DMA_CONFIG()
{
ADC_InitTypeDef ADC_InitStructure; 
DMA_InitTypeDef DMA_InitStructure; 
GPIO_InitTypeDef GPIO_InitStructure; 
SysTick_Config(SystemCoreClock/1000); 
/*************************************************/
/*Configure AHB Peripheral Clocks for PA.1 & PA.2*/
/* ANALOG INPUT PINS */
/*************************************************/
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1 | GPIO_Pin_2; 
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN; 
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL ; 
GPIO_Init(GPIOA, &GPIO_InitStructure);
/*************************************************/
/*Configure AHB Peripheral Clocks for PC.9 & PC.8*/
/* LEDS */
/*************************************************/
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOC, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8 | GPIO_Pin_9;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT; 
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; 
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_Level_1; 
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; 
GPIO_Init(GPIOC, &GPIO_InitStructure);
/************************************************/
/* Configure ADC and DMA in nested statements */
/* Somehow confusing but it works compared to */
/* seperate configuration methods */
/************************************************/
ADC_DeInit(ADC1); 
RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE); 
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1 , ENABLE); 
/************************************************/
/* DMA Configuration */
/************************************************/
DMA_DeInit(DMA1_Channel1);
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)ADC1_DR_Address; 
DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)ADC1_val; 
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStructure.DMA_BufferSize = 2; 
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; 
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_M2M = DMA_M2M_Disable;
DMA_Init(DMA1_Channel1, &DMA_InitStructure);
DMA_Cmd(DMA1_Channel1, ENABLE); 
ADC_DMARequestModeConfig(ADC1, ADC_DMAMode_Circular); 
ADC_DMACmd(ADC1, ENABLE); 
/************************************************/
/* ADC Configuration */
/************************************************/
ADC_StructInit(&ADC_InitStructure); /
ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; 
ADC_InitStructure.ADC_ScanDirection = ADC_ScanDirection_Backward;
ADC_Init(ADC1, &ADC_InitStructure);
/*ADC_Channel_1 ->PA.1 - Conversion period at 5 Cycles (enough for small impedance) */
ADC_ChannelConfig(ADC1, ADC_Channel_1 , ADC_SampleTime_55_5Cycles);
/*ADC_Channel_2 ->PA.2 - Conversion period at 5 Cycles (enough for small impedance) */
ADC_ChannelConfig(ADC1, ADC_Channel_2 , ADC_SampleTime_55_5Cycles);
ADC_GetCalibrationFactor(ADC1); 
ADC_Cmd(ADC1, ENABLE); 
while(!ADC_GetFlagStatus(ADC1, ADC_FLAG_ADEN)); 
ADC_StartOfConversion(ADC1); 
}

1 REPLY 1
Posted on October 15, 2015 at 06:44

I'm not using Cortex-M0 parts, but I've posted some code I think should be working. Start with that.

https://my.st.com/public/STe2ecommunities/mcu/Lists/cortex_mx_stm32/Flat.aspx?RootFolder=https://my.st.com/public/STe2ecommunities/mcu/Lists/cortex_mx_stm32/STM32F0%20ADC-DMA%20touble&FolderCTID=0x01200200770978C69A1141439FE559EB459D7580009C4E14902C3CDE46A77F0FFD06506F5B&currentviews=1766

Tips, buy me a coffee, or three.. PayPal Venmo Up vote any posts that you find helpful, it shows what's working..