ADC1输出

1万 · 2020-10-11 12:44

我的ADC1输出要么是2啊3啊8啊，要么就是输出4095或者4092或者4088，就是没有中间值，我测了我的AD端口当模拟输入为0V时，ADC1转换结果是2~8，当模拟输入0.16V时ADC1输出4084~4095，是PC0（模拟输入）最大也才1V，这个是哪哪了问题？麻烦帮我看看，谢谢了。

1万 · 2020-10-11 12:47

楼主程序可以公开吗？贴程序看下吧，这么说看不出什么原因

1万 · 2020-10-11 12:50

ADC初始化代码如下：
void Adc_Init(void)
{
ADC_InitTypeDef    ADC_InitStructure;
DMA_InitTypeDef    DMA_InitStructure;
GPIO_InitTypeDef    GPIO_InitStructure;

//时钟使能
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC|RCC_APB2Periph_ADC1, ENABLE );
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
RCC_ADCCLKConfig(RCC_PCLK2_Div6);
//IO初始化
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_1|GPIO_Pin_2|GPIO_Pin_3|GPIO_Pin_4|GPIO_Pin_5;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_Init(GPIOC, &GPIO_InitStructure);
  //DMA初始化
DMA_DeInit(DMA1_Channel1);
DMA_InitStructure.DMA_PeripheralBaseAddr = (u32)&(ADC1->DR);
DMA_InitStructure.DMA_MemoryBaseAddr = (u32)&ADCConvertedValue;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStructure.DMA_BufferSize = 12;
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_Medium;
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA1_Channel1, &DMA_InitStructure);

DMA_Cmd(DMA1_Channel1, ENABLE);
//ADC1初始化
ADC_DeInit(ADC1);
ADC_InitStructure.ADC_Mode = ADC_Mode_Independent;
ADC_InitStructure.ADC_ScanConvMode = ENABLE;
ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
ADC_InitStructure.ADC_NbrOfChannel = 6;
ADC_Init(ADC1, &ADC_InitStructure);

ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_239Cycles5 );
ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 2, ADC_SampleTime_239Cycles5 );
ADC_RegularChannelConfig(ADC1, ADC_Channel_2, 3, ADC_SampleTime_239Cycles5 );
ADC_RegularChannelConfig(ADC1, ADC_Channel_3, 4, ADC_SampleTime_239Cycles5 );
ADC_RegularChannelConfig(ADC1, ADC_Channel_4, 5, ADC_SampleTime_239Cycles5 );
ADC_RegularChannelConfig(ADC1, ADC_Channel_5, 6, ADC_SampleTime_239Cycles5 );

ADC_DMACmd(ADC1, ENABLE);

ADC_Cmd(ADC1, ENABLE);
ADC_ResetCalibration(ADC1);
while(ADC_GetResetCalibrationStatus(ADC1));
ADC_StartCalibration(ADC1);
while(ADC_GetCalibrationStatus(ADC1));

ADC_SoftwareStartConvCmd(ADC1, ENABLE);

}

2万 · 2020-10-11 12:54

/* Includes ------------------------------------------------------------------*/
#include "main.h"

/** @addtogroup STM32F7xx_HAL_Examples
  * @{
  */

/** @addtogroup ADC_RegularConversion_DMA
  * @{
  */

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* ADC handler declaration */
ADC_HandleTypeDef AdcHandle;

/* Variable used to get converted value */
__IO uint16_t uhADCxConvertedValue = 0;

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void Error_Handler(void);
static void MPU_Config(void);
static void CPU_CACHE_Enable(void);

/* Private functions ---------------------------------------------------------*/

/**
  * @brief  Main program.
  * @param  None
  * @retval None
  */
int main(void)
{
  ADC_ChannelConfTypeDef sConfig;

  /* Configure the MPU attributes as Write Through */
  MPU_Config();

  /* Enable the CPU Cache */
  CPU_CACHE_Enable();

  /* STM32F7xx HAL library initialization:
   - Configure the Flash prefetch
   - Systick timer is configured by default as source of time base, but user
      can eventually implement his proper time base source (a general purpose
      timer for example or other time source), keeping in mind that Time base
      duration should be kept 1ms since PPP_TIMEOUT_VALUEs are defined and
      handled in milliseconds basis.
   - Set NVIC Group Priority to 4
   - Low Level Initialization
   */
  HAL_Init();

  /* Configure the system clock to 216 MHz */
  SystemClock_Config();

  /* Configure LED1 */
  BSP_LED_Init(LED1);

  /*##-1- Configure the ADC peripheral #######################################*/
  AdcHandle.Instance       = ADCx;

  AdcHandle.Init.ClockPrescaler       = ADC_CLOCKPRESCALER_PCLK_DIV4;
  AdcHandle.Init.Resolution          = ADC_RESOLUTION_12B;
  AdcHandle.Init.ScanConvMode       = DISABLE;                      /* Sequencer disabled (ADC conversion on only 1 channel: channel set on rank 1) */
  AdcHandle.Init.ContinuousConvMode = ENABLE;                      /* Continuous mode disabled to have only 1 conversion at each conversion trig */
  AdcHandle.Init.DiscontinuousConvMode = DISABLE;                      /* Parameter discarded because sequencer is disabled */
  AdcHandle.Init.NbrOfDiscConversion = 0;
  AdcHandle.Init.ExternalTrigConvEdge  = ADC_EXTERNALTRIGCONVEDGE_NONE;       /* Conversion start trigged at each external event */
  AdcHandle.Init.ExternalTrigConv    = ADC_EXTERNALTRIGCONV_T1_CC1;
  AdcHandle.Init.DataAlign          = ADC_DATAALIGN_RIGHT;
  AdcHandle.Init.NbrOfConversion    = 1;
  AdcHandle.Init.DMAContinuousRequests = ENABLE;
  AdcHandle.Init.EOCSelection       = DISABLE;

  if (HAL_ADC_Init(&AdcHandle) != HAL_OK)
  {
/* ADC initialization Error */
Error_Handler();
  }

  /*##-2- Configure ADC regular channel ######################################*/
  sConfig.Channel    = ADC_CHANNEL_8;
  sConfig.Rank       = 1;
  sConfig.SamplingTime = ADC_SAMPLETIME_3CYCLES;
  sConfig.Offset    = 0;

  if (HAL_ADC_ConfigChannel(&AdcHandle, &sConfig) != HAL_OK)
  {
/* Channel Configuration Error */
Error_Handler();
  }

  /*##-3- Start the conversion process #######################################*/
  if(HAL_ADC_Start_DMA(&AdcHandle, (uint32_t*)&uhADCxConvertedValue, 1) != HAL_OK)
  {
/* Start Conversation Error */
Error_Handler();
  }

  /* Infinite loop */
  while (1)
  {
if (uhADCxConvertedValue > 2700)
{
   BSP_LED_Off(LED1);
}
else
{
   BSP_LED_On(LED1);
}
  }
}

/**
  * @brief  System Clock Configuration
  *       The system Clock is configured as follow :
  *          System Clock source          = PLL (HSE)
  *          SYSCLK(Hz)                   = 216000000
  *          HCLK(Hz)                      = 216000000
  *          AHB Prescaler                = 1
  *          APB1 Prescaler                = 4
  *          APB2 Prescaler                = 2
  *          HSE Frequency(Hz)             = 25000000
  *          PLL_M                         = 25
  *          PLL_N                         = 432
  *          PLL_P                         = 2
  *          PLL_Q                         = 9
  *          VDD(V)                      = 3.3
  *          Main regulator output voltage  = Scale1 mode
  *          Flash Latency(WS)             = 7
  * @param  None
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_ClkInitTypeDef RCC_ClkInitStruct;
  RCC_OscInitTypeDef RCC_OscInitStruct;
  HAL_StatusTypeDef ret = HAL_OK;

  /* Enable HSE Oscillator and activate PLL with HSE as source */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM = 25;
  RCC_OscInitStruct.PLL.PLLN = 432;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
  RCC_OscInitStruct.PLL.PLLQ = 9;

  ret = HAL_RCC_OscConfig(&RCC_OscInitStruct);
  if(ret != HAL_OK)
  {
while(1) { ; }
  }

  /* Activate the OverDrive to reach the 216 MHz Frequency */
  ret = HAL_PWREx_EnableOverDrive();
  if(ret != HAL_OK)
  {
while(1) { ; }
  }

  /* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 clocks dividers */
  RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;

  ret = HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_7);
  if(ret != HAL_OK)
  {
while(1) { ; }
  }
}

/**
  * @brief  This function is executed in case of error occurrence.
  * @param  None
  * @retval None
  */
static void Error_Handler(void)
{
  while (1)
  {
/* LED1 blinks */
BSP_LED_Toggle(LED1);
HAL_Delay(20);
  }
}

/**
  * @brief  Conversion complete callback in non blocking mode
  * @param  AdcHandle : AdcHandle handle
  * @NOTE This example shows a simple way to report end of conversion, and
  *       you can add your own implementation.
  * @retval None
  */
void HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef* AdcHandle)
{
  /* Turn LED1 on: Transfer process is correct */
  BSP_LED_On(LED1);
}

#ifdef  USE_FULL_ASSERT

/**
  * @brief  Reports the name of the source file and the source line number
  *       where the assert_param error has occurred.
  * @param  file: pointer to the source file name
  * @param  line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* User can add his own implementation to report the file name and line number,
   ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */

  /* Infinite loop */
  while (1)
  {
  }
}

#endif

/**
  * @brief  Configure the MPU attributes as Write Through for SRAM1/2.
  * @NOTE The Base Address is 0x20010000 since this memory interface is the AXI.
  *       The Region Size is 256KB, it is related to SRAM1 and SRAM2  memory size.
  * @param  None
  * @retval None
  */
static void MPU_Config(void)
{
  MPU_Region_InitTypeDef MPU_InitStruct;

  /* Disable the MPU */
  HAL_MPU_Disable();

  /* Configure the MPU attributes as WT for SRAM */
  MPU_InitStruct.Enable = MPU_REGION_ENABLE;
  MPU_InitStruct.BaseAddress = 0x20010000;
  MPU_InitStruct.Size = MPU_REGION_SIZE_256KB;
  MPU_InitStruct.AccessPermission = MPU_REGION_FULL_ACCESS;
  MPU_InitStruct.IsBufferable = MPU_ACCESS_NOT_BUFFERABLE;
  MPU_InitStruct.IsCacheable = MPU_ACCESS_CACHEABLE;
  MPU_InitStruct.IsShareable = MPU_ACCESS_NOT_SHAREABLE;
  MPU_InitStruct.Number = MPU_REGION_NUMBER0;
  MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
  MPU_InitStruct.SubRegionDisable = 0x00;
  MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_ENABLE;

  HAL_MPU_ConfigRegion(&MPU_InitStruct);

  /* Enable the MPU */
  HAL_MPU_Enable(MPU_PRIVILEGED_DEFAULT);
}

/**
  * @brief  CPU L1-Cache enable.
  * @param  None
  * @retval None
  */
static void CPU_CACHE_Enable(void)
{
  /* Enable I-Cache */
  SCB_EnableICache();

  /* Enable D-Cache */
  SCB_EnableDCache();
}

/**
  * @}
  */

/**
  * @}
  */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

1万 · 2020-10-11 13:10

要开启管脚的复用功能的时钟： RCC_APB2Periph_AFIO

1万 · 2020-10-11 13:14

ADC用的片上吗，参考电压是多少

1万 · 2020-10-11 13:17

我试了的，还是一样的结果，，，

1万 · 2020-10-11 13:20

片上AD电路是什么样的

1万 · 2020-10-11 13:24

你的AD输入电压是如何输入的，发电路上来看看

1万 · 2020-10-11 13:29

参考电压直接和3.3V电源电压接在一起，麻烦帮我分析下哪些地方可能出问题

1万 · 2020-10-11 13:33

你用表测量过AD相关管脚的电压了吗？

1万 · 2020-10-11 13:37

烧官方的例程看看。不应该吧，AD是很简单的

1万 · 2020-10-11 13:41

模拟输入口我都测量了，当时0.06V时候AD转换结果是8，模拟输入口电压接近0.16V时候AD结果是4085，就没有中间值，本身是个很简单的东西，各种都测了，现在没得办法，麻烦帮我分析下，不行只有换片子了，，，

1万 · 2020-10-11 13:44

另外，我用的是STM32F103VC -100脚的片子，，，前一版用STM32F103RB的片子AD没有问题，不知道是不是片子问题，，，

1万 · 2020-10-11 13:47

Vref+和Vref-管脚有测量过没？要在单片机的管脚上测量，不要在走线上测量

1万 · 2020-10-11 13:50

不要在走线上测量，以便确认硬件焊接没问题。

1万 · 2020-10-11 13:54

我都对比了不知道多少次了，，

2万 · 2020-10-11 13:59

你就一块PCBA吗？有的话，换一块试试。

1万 · 2020-10-11 14:02

很低级的错误，，我把通道10弄成通道0了

2万 · 2020-10-11 14:05

楼主问题解决了就好，感觉写的最多的就是初始化了，也是很容易忽视的地方。