多路AD DMA模式，输出问题，在线求救？

只看该作者 · 2016-9-9 16:33

ADC初始化

void MX_ADC_Init(void)
{

ADC_ChannelConfTypeDef sConfig;
GPIO_InitTypeDef GPIO_InitStruct;
/* Peripheral clock enable */

__HAL_RCC_GPIOA_CLK_ENABLE();
__HAL_RCC_ADC1_CLK_ENABLE();

GPIO_InitStruct.Pin = GPIO_PIN_6|GPIO_PIN_7;
GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
GPIO_InitStruct.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

hadc.Instance = ADC1;
if (HAL_ADC_DeInit(&hadc) != HAL_OK)
{
      Error_Handler();
}

hadc.Instance = ADC1;
hadc.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV4;
hadc.Init.Resolution = ADC_RESOLUTION_12B;
hadc.Init.DataAlign = ADC_DATAALIGN_RIGHT;
hadc.Init.ScanConvMode = ADC_SCAN_ENABLE;
hadc.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
hadc.Init.LowPowerAutoWait = DISABLE;
hadc.Init.LowPowerAutoPowerOff = DISABLE;
hadc.Init.ContinuousConvMode = ENABLE;
hadc.Init.DiscontinuousConvMode = DISABLE;
hadc.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
hadc.Init.DMAContinuousRequests = ENABLE;
hadc.Init.Overrun = ADC_OVR_DATA_PRESERVED;
if (HAL_ADC_Init(&hadc) != HAL_OK)
{
      Error_Handler();
}

/* ### - 2 - Start calibration ############################################ */
if (HAL_ADCEx_Calibration_Start(&hadc) != HAL_OK)
{
      Error_Handler();
}

/**Configure for the selected ADC regular channel to be converted.
*/
sConfig.Channel = ADC_CHANNEL_6;
sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
sConfig.SamplingTime = ADC_SAMPLETIME_239CYCLES_5;

if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
{
      Error_Handler();
}

sConfig.Channel = ADC_CHANNEL_7;
sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
sConfig.SamplingTime = ADC_SAMPLETIME_239CYCLES_5;

if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
{
      Error_Handler();
}
/* ### - 4 - Start conversion in DMA mode ################################# */
if (HAL_ADC_Start(&hadc) != HAL_OK)
{
      Error_Handler();
}

}

DMA初始化

static void MX_DMA_Init(void)
{
/* DMA controller clock enable */
__HAL_RCC_DMA1_CLK_ENABLE();

/* DMA interrupt init */
/* DMA1_Channel1_IRQn interrupt configuration */
HAL_NVIC_SetPriority(DMA1_Channel1_IRQn, 0, 0);
HAL_NVIC_EnableIRQ(DMA1_Channel1_IRQn);

}

__IO uint32_t ADC_Value[2];
uint32_t ad0,ad1;

int main(void)

{

.....//此处省略一些

MX_ADC6_Init();
HAL_ADC_Start_DMA(&hadc, (uint32_t*)&ADC_Value, 2);

while(1)

{

      HAL_Delay(500);
      ad0 = ADC_Value[0];

      ad1 = ADC_Value[1];

      printf("\r\n******** ADC DMA Example ********\r\n\r\n");

      printf(" AD0 value = %1.3fV \r\n", ad0*3.3f/4096);

      printf(" AD1 value = %1.3fV \r\n", ad1*3.3f/4096);
   }

}

输出结果：

******** ADC DMA Example ********

AD0 value = 0.000V
AD1 value = 0.000V

然而这两个引脚是都有电压的。求救呀？

只看该作者 · 2016-9-9 16:57

有人在吗？？

只看该作者 · 2016-9-12 10:06

电子技术论坛算是没人了

只看该作者 · 2016-9-12 11:15

代码太长没看，输出值为零，的话，看看转换速度是不是太快了。

只看该作者 · 2016-9-12 14:42

你DMA配置了吗？