Posted on July 13, 2018 at 22:03Hello community! I've got a problem with DMA and ADC (multi channel). I can't find solution why function
HAL_ADC_Start_DMA returns 0's to the 'adc_value' array. I have connected to Nucleo F466RE board 3 sensors, and i want to measure and get 3 values. Thanks for any prompts.
#include 'stm32f4xx.h'
#include 'stm32f4xx_nucleo.h'
DMA_HandleTypeDef dma;
UART_HandleTypeDef uart;
uint32_t adc_value[3];
char result[20]='';
int main(void)
{
HAL_Init();
__HAL_RCC_DMA1_CLK_ENABLE();
__GPIOA_CLK_ENABLE();
__USART2_CLK_ENABLE();
__ADC1_CLK_ENABLE();
GPIO_InitTypeDef gpioANALOG;
gpioANALOG.Pin = GPIO_PIN_0|GPIO_PIN_4|GPIO_PIN_1;
gpioANALOG.Mode = GPIO_MODE_ANALOG;
gpioANALOG.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOA, &gpioANALOG);
GPIO_InitTypeDef gpioUART;
gpioUART.Pin = GPIO_PIN_3|GPIO_PIN_2;
gpioUART.Mode = GPIO_MODE_AF_PP;
gpioUART.Alternate = GPIO_AF7_USART2;
gpioUART.Speed = GPIO_SPEED_HIGH;
gpioUART.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOA, &gpioUART);
uart.Instance = USART2;
uart.Init.BaudRate = 9600;
uart.Init.WordLength = UART_WORDLENGTH_8B;
uart.Init.StopBits = UART_STOPBITS_1;
uart.Init.Parity = UART_PARITY_NONE;
uart.Init.Mode = UART_MODE_TX_RX;
uart.Init.HwFlowCtl = UART_HWCONTROL_NONE;
uart.Init.OverSampling = UART_OVERSAMPLING_16;
HAL_UART_Init(&uart);
ADC_HandleTypeDef adc;
adc.Instance = ADC1;
adc.Init.ContinuousConvMode = ENABLE;
adc.Init.ExternalTrigConv = ADC_SOFTWARE_START;
adc.Init.DataAlign = ADC_DATAALIGN_RIGHT;
adc.Init.ScanConvMode = ENABLE;
adc.Init.DiscontinuousConvMode = DISABLE;
adc.Init.NbrOfConversion = 3;
HAL_ADC_Init(&adc);
ADC_ChannelConfTypeDef adcChannel;
adcChannel.Channel = ADC_CHANNEL_0;
adcChannel.Rank = 1;
adcChannel.SamplingTime = ADC_SAMPLETIME_480CYCLES;
HAL_ADC_ConfigChannel(&adc, &adcChannel);
adcChannel.Channel = ADC_CHANNEL_1;
adcChannel.Rank = 2;
adcChannel.SamplingTime = ADC_SAMPLETIME_480CYCLES;
HAL_ADC_ConfigChannel(&adc, &adcChannel);
adcChannel.Channel = ADC_CHANNEL_2;
adcChannel.Rank = 3;
adcChannel.SamplingTime = ADC_SAMPLETIME_480CYCLES;
HAL_ADC_ConfigChannel(&adc, &adcChannel);
dma.Instance = DMA1_Stream1;
dma.Init.Direction = DMA_PERIPH_TO_MEMORY;
dma.Init.PeriphInc = DMA_PINC_ENABLE;
dma.Init.MemInc = DMA_MINC_ENABLE;
dma.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD;
dma.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD;
dma.Init.Mode = DMA_CIRCULAR;
dma.Init.Priority = DMA_PRIORITY_HIGH;
HAL_DMA_Init(&dma);
__HAL_LINKDMA(&adc,DMA_Handle,dma);
HAL_ADC_Start_DMA(&adc,(uint32_t*)adc_value,3);
sprintf(result,'ADC: %lu \n\r',adc_value[0]);
HAL_UART_Transmit(&uart,result,sizeof(result),100);
while(1)
{
}
}
