欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识！
您现在的位置是： 首页  >  科技

STM32内部参考电压+DMA精准采集电池电压

程序员文章站 2022-06-22 19:27:22
最近项目又遇到了电池电压采集，锂电池的电压范围是4.2到2.8一般，当锂电池低于3.3V时，单片机供电电压会小于3.3V，那么电池电压参考计算4096就不能对应3.3,所以必须采用内部参考电压。（我项目中用到的是RP104N331 LDO，实际上当电池电压在3.5V左右时，LDO输出就已经不是3.3V，严重影响精度）VREFINT_CAL = *(__IO uint16_t *)(0X1FF80078);首先需要从数据手册知道VREFINT_CAL 的地址信息，读出16的值，所以这里采用了 uint1...

最近项目又遇到了电池电压采集，锂电池的电压范围是4.2到2.8一般，当锂电池低于3.3V时，单片机供电电压会小于3.3V，那么电池电压参考计算4096就不能对应3.3,所以必须采用内部参考电压。（我项目中用到的是RP104N331 LDO，实际上当电池电压在3.5V左右时，LDO输出就已经不是3.3V，严重影响精度）

VREFINT_CAL = *(__IO uint16_t *)(0X1FF80078);

首先需要从数据手册知道VREFINT_CAL 的地址信息，读出16的值，所以这里采用了 uint16_t
同时stm32 开启两路ADC，一路是要采集的ADC，一路是内部参考电压

	ADC_ChannelConfTypeDef sConfig = {0};
	VREFINT_CAL = *(__IO uint16_t *)(0X1FF80078);
	V_temp1 = 3.3 / 4096 * (float)ADC_buffer[0] / 0.6;
	VDDA = 3 * VREFINT_CAL/(float)ADC_buffer[1];
	V_temp2 = VDDA/4096 * (float)ADC_buffer[0] / 0.6;
	printf("VDDA %f \r\n",VDDA);
	printf("%f V %f V\r\n",V_temp1,V_temp2);
	printf("%d %d\r\n",ADC_buffer[0],ADC_buffer[1]);

V1是常规的3.3V作为参考电压，VDDA可以通过VREFINT_CAL 计算得出，V_temp2是以VDDA得出，经过开关电源测试，V_temp2误差基本保持在0.01V

由于我们采集双通道，所以采用DMA传输

这里有几个参数需要注意，一个是ClockPrescaler，我这里采用ADC_CLOCK_ASYNC_DIV128，分频不同居然采集的电压不同，而且误差极大，这里一直找不到相关原因，另一个是LowPowerFrequencyMode，由于这里分频比较大，导致采用时钟很低，所以ENABLE，具体低于多少打开手册有要求，但是实测使能或者不使能差别并不是很大，最后在初始化完成之后需要增加校准函数HAL_ADCEx_Calibration_Start

下面是adc.c源码,这里的DMA是连续采集，只需在主函数开启一次HAL_ADC_Start_DMA(&hadc, (uint32_t *)ADC_buffer, 2)

/**
  ******************************************************************************
  * File Name          : ADC.c
  * Description        : This file provides code for the configuration
  *                      of the ADC instances.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright (c) 2020 STMicroelectronics.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by ST under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************
  */

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

/* USER CODE BEGIN 0 */
__IO uint32_t uwADCxConvertedValue1 = 0;
__IO uint32_t uwADCxConvertedValue2 = 0;
__IO uint16_t VREFINT_CAL ;
float V_temp1,V_temp2,VDDA;
extern uint32_t ADC_buffer[2];
/* USER CODE END 0 */

ADC_HandleTypeDef hadc;
DMA_HandleTypeDef hdma_adc;

/* ADC init function */
void MX_ADC_Init(void)
{
  ADC_ChannelConfTypeDef sConfig = {0};

  /** Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion) 
  */
  hadc.Instance = ADC1;
  hadc.Init.OversamplingMode = DISABLE;
  hadc.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV128;
  hadc.Init.Resolution = ADC_RESOLUTION_12B;
  hadc.Init.SamplingTime = ADC_SAMPLETIME_12CYCLES_5;
  hadc.Init.ScanConvMode = ADC_SCAN_DIRECTION_FORWARD;
  hadc.Init.DataAlign = ADC_DATAALIGN_RIGHT;
  hadc.Init.ContinuousConvMode = ENABLE;
  hadc.Init.DiscontinuousConvMode = DISABLE;
  hadc.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
  hadc.Init.ExternalTrigConv = ADC_SOFTWARE_START;
  hadc.Init.DMAContinuousRequests = ENABLE;
  hadc.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
  hadc.Init.Overrun = ADC_OVR_DATA_PRESERVED;
  hadc.Init.LowPowerAutoWait = DISABLE;
  hadc.Init.LowPowerFrequencyMode = ENABLE;
  hadc.Init.LowPowerAutoPowerOff = DISABLE;
  if (HAL_ADC_Init(&hadc) != HAL_OK)
  {
    Error_Handler();
  }
	
	if (HAL_ADCEx_Calibration_Start(&hadc, ADC_SINGLE_ENDED) !=  HAL_OK)
		{
    Error_Handler();
		}
  /** Configure for the selected ADC regular channel to be converted. 
  */
  sConfig.Channel = ADC_CHANNEL_1;
  sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
  if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /** Configure for the selected ADC regular channel to be converted. 
  */
  sConfig.Channel = ADC_CHANNEL_VREFINT;
  if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }

}

void HAL_ADC_MspInit(ADC_HandleTypeDef* adcHandle)
{

  GPIO_InitTypeDef GPIO_InitStruct = {0};
  if(adcHandle->Instance==ADC1)
  {
  /* USER CODE BEGIN ADC1_MspInit 0 */

  /* USER CODE END ADC1_MspInit 0 */
    /* ADC1 clock enable */
    __HAL_RCC_ADC1_CLK_ENABLE();
  
    __HAL_RCC_GPIOA_CLK_ENABLE();
    /**ADC GPIO Configuration    
    PA1     ------> ADC_IN1 
    */
    GPIO_InitStruct.Pin = GPIO_PIN_1;
    GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

    /* ADC1 DMA Init */
    /* ADC Init */
    hdma_adc.Instance = DMA1_Channel1;
    hdma_adc.Init.Request = DMA_REQUEST_0;
    hdma_adc.Init.Direction = DMA_PERIPH_TO_MEMORY;
    hdma_adc.Init.PeriphInc = DMA_PINC_DISABLE;
    hdma_adc.Init.MemInc = DMA_MINC_ENABLE;
    hdma_adc.Init.PeriphDataAlignment = DMA_PDATAALIGN_WORD;
    hdma_adc.Init.MemDataAlignment = DMA_MDATAALIGN_WORD;
    hdma_adc.Init.Mode = DMA_CIRCULAR;
    hdma_adc.Init.Priority = DMA_PRIORITY_LOW;
    if (HAL_DMA_Init(&hdma_adc) != HAL_OK)
    {
      Error_Handler();
    }

    __HAL_LINKDMA(adcHandle,DMA_Handle,hdma_adc);

  /* USER CODE BEGIN ADC1_MspInit 1 */
//		if (HAL_ADCEx_Calibration_Start(&hadc, ADC_SINGLE_ENDED) !=  HAL_OK)
//		{
//    Error_Handler();
//		}
  /* USER CODE END ADC1_MspInit 1 */
  }
}

void HAL_ADC_MspDeInit(ADC_HandleTypeDef* adcHandle)
{

  if(adcHandle->Instance==ADC1)
  {
  /* USER CODE BEGIN ADC1_MspDeInit 0 */

  /* USER CODE END ADC1_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_ADC1_CLK_DISABLE();
  
    /**ADC GPIO Configuration    
    PA1     ------> ADC_IN1 
    */
    HAL_GPIO_DeInit(GPIOA, GPIO_PIN_1);

    /* ADC1 DMA DeInit */
    HAL_DMA_DeInit(adcHandle->DMA_Handle);
  /* USER CODE BEGIN ADC1_MspDeInit 1 */

  /* USER CODE END ADC1_MspDeInit 1 */
  }
} 

/* USER CODE BEGIN 1 */
void Acquisition_voltage()
{
	//float VDDA;
	ADC_ChannelConfTypeDef sConfig = {0};
	VREFINT_CAL = *(__IO uint16_t *)(0X1FF80078);
	V_temp1 = 3.3 / 4096 * (float)ADC_buffer[0] / 0.6;
	VDDA = 3 * VREFINT_CAL/(float)ADC_buffer[1];
	V_temp2 = VDDA/4096 * (float)ADC_buffer[0] / 0.6;
	printf("VDDA %f \r\n",VDDA);
	printf("%f V %f V\r\n",V_temp1,V_temp2);
	printf("%d %d\r\n",ADC_buffer[0],ADC_buffer[1]);
  
	
//	//printf("VREFINT_CAL %d \r\n",VREFINT_CAL);
	
	sConfig.Channel = ADC_CHANNEL_1;
  sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
  if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
//	
//	
//	if (HAL_ADC_Start(&hadc) != HAL_OK)
//  {
//    /* Start Conversation Error */
//    Error_Handler();
//  }
//	
//   HAL_ADC_PollForConversion(&hadc, 1000);
//  
//	/* Check if the continous conversion of regular channel is finished */
//	if ((HAL_ADC_GetState(&hadc) & HAL_ADC_STATE_REG_EOC) == HAL_ADC_STATE_REG_EOC)
//	{
//		/*##-6- Get the converted value of regular channel  ########################*/
//		uwADCxConvertedValue1 = HAL_ADC_GetValue(&hadc);
//		
//	}
//	
	printf("uwADCxConvertedValue1 %d\r\n",uwADCxConvertedValue1);
//	V_temp = 3.3 / 4096 * uwADCxConvertedValue1 / 0.6;
//	printf("V_temp %f V\r\n",V_temp);

	sConfig.Channel = ADC_CHANNEL_17;
  sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
  if (HAL_ADC_ConfigChannel(&hadc, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
//	
//	
//	if (HAL_ADC_Start(&hadc) != HAL_OK)
//  {
//    /* Start Conversation Error */
//    Error_Handler();
//  }
//	
//   HAL_ADC_PollForConversion(&hadc, 1000);
//  
//	/* Check if the continous conversion of regular channel is finished */
//	if ((HAL_ADC_GetState(&hadc) & HAL_ADC_STATE_REG_EOC) == HAL_ADC_STATE_REG_EOC)
//	{
//		/*##-6- Get the converted value of regular channel  ########################*/
//		uwADCxConvertedValue2 = HAL_ADC_GetValue(&hadc);
//	}
//	
//	printf("uwADCxConvertedValue2 %d\r\n",uwADCxConvertedValue2);
	
	
	
}
/* USER CODE END 1 */

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

本文地址：https://blog.csdn.net/qq_36097683/article/details/108580900

相关标签： c语言 单片机

上一篇： 采用机器学习方式对网站进行数据挖掘的经验指南

下一篇： Flash cs6怎么定义模板方法?

推荐阅读