代码收藏家技术教程 2024-07-07

STM32应用中的NTC热敏电阻

记录一下怎么用STM32搭配NTC热敏电阻测温度

本文用到的是SM32F103C8T6 + 10K B3435 热敏电阻

接线图

红色的线就是接线部分（比较简陋）

cubemx配置

使用cubemx

1.晶振

3. ADC配置，我这里选择的是通道1 也就是PA0 其他默认

4.usart 配置用于串口的输出可以直观看到数据

5. 如果需要的话可以开个GPIO用于开始时候确认是否配置成功

9。最后点生成

写代码

在usart中添加串口重定向

/* USER CODE BEGIN Header */
/**
 ******************************************************************************
 * @file    usart.c
 * @brief   This file provides code for the configuration
 *          of the USART instances.
 ******************************************************************************
 * @attention
 *
 * Copyright (c) 2023 STMicroelectronics.
 * All rights reserved.
 *
 * This software is licensed under terms that can be found in the LICENSE file
 * in the root directory of this software component.
 * If no LICENSE file comes with this software, it is provided AS-IS.
 *
 ******************************************************************************
 */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "usart.h"

/* USER CODE BEGIN 0 */
#include "stdio.h"
/* 加入以下代码, 支持printf函数, 而不??要???择use MicroLIB */

#if 1

#if (__ARMCC_VERSION >= 6010050)           /* 使用AC6编译器时 */
__asm(".global __use_no_semihosting\n\t"); /* 声明不使用半主机模式 */
__asm(".global __ARM_use_no_argv \n\t");   /* AC6下需要声明main函数为无参数格式，否则部分例程可能出现半主机模式 */

#else
/* 使用AC5编译器时, 要在这里定义__FILE ?? 不使用半主机模式 */
#pragma import(__use_no_semihosting)

struct __FILE
{
  int handle;
  /* Whatever you require here. If the only file you are using is */
  /* standard output using printf() for debugging, no file handling */
  /* is required. */
};

#endif

/* 不使用半主机模式，至少需要重定义_ttywrch\_sys_exit\_sys_command_string函数,以同时兼容AC6和AC5模式 */
int _ttywrch(int ch)
{
  ch = ch;
  return ch;
}

/* 定义_sys_exit()以避免使用半主机模式 */
void _sys_exit(int x)
{
  x = x;
}

char *_sys_command_string(char *cmd, int len)
{
  return NULL;
}

/* FILE ?? stdio.h里面定义. */
FILE __stdout;

/* MDK下需要重定义fputc函数, printf函数??终会通过调用fputc输出字符串到串口 */
int fputc(int ch, FILE *f)
{
  while ((USART1->SR & 0X40) == 0)
    ; /* 等待上一个字符发送完?? */

  USART1->DR = (uint8_t)ch; /* 将要发???的字符 ch 写入到DR寄存?? */
  return ch;
}
#endif
/******************************************************************************************/

uint8_t g_rx_buffer[1];       /* HAL库使用的串口接收数据缓冲?? */
uint8_t g_usart1_rx_flag = 0; /* 串口接收到数据标?? */
/* USER CODE END 0 */

UART_HandleTypeDef huart1;

/* USART1 init function */

void MX_USART1_UART_Init(void)
{

  /* USER CODE BEGIN USART1_Init 0 */

  /* USER CODE END USART1_Init 0 */

  /* USER CODE BEGIN USART1_Init 1 */

  /* USER CODE END USART1_Init 1 */
  huart1.Instance = USART1;
  huart1.Init.BaudRate = 115200;
  huart1.Init.WordLength = UART_WORDLENGTH_8B;
  huart1.Init.StopBits = UART_STOPBITS_1;
  huart1.Init.Parity = UART_PARITY_NONE;
  huart1.Init.Mode = UART_MODE_TX_RX;
  huart1.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart1.Init.OverSampling = UART_OVERSAMPLING_16;
  if (HAL_UART_Init(&huart1) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN USART1_Init 2 */
  HAL_UART_Receive_IT(&huart1, (uint8_t *)g_rx_buffer, 1);
  /* USER CODE END USART1_Init 2 */
}

void HAL_UART_MspInit(UART_HandleTypeDef *uartHandle)
{

  GPIO_InitTypeDef GPIO_InitStruct = {0};
  if (uartHandle->Instance == USART1)
  {
    /* USER CODE BEGIN USART1_MspInit 0 */

    /* USER CODE END USART1_MspInit 0 */
    /* USART1 clock enable */
    __HAL_RCC_USART1_CLK_ENABLE();

    __HAL_RCC_GPIOA_CLK_ENABLE();
    /**USART1 GPIO Configuration
    PA9     ------> USART1_TX
    PA10     ------> USART1_RX
    */
    GPIO_InitStruct.Pin = GPIO_PIN_9;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

    GPIO_InitStruct.Pin = GPIO_PIN_10;
    GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

    /* USER CODE BEGIN USART1_MspInit 1 */
    HAL_NVIC_SetPriority(USART1_IRQn, 3, 0);
    HAL_NVIC_EnableIRQ(USART1_IRQn);
    /* USER CODE END USART1_MspInit 1 */
  }
}

void HAL_UART_MspDeInit(UART_HandleTypeDef *uartHandle)
{

  if (uartHandle->Instance == USART1)
  {
    /* USER CODE BEGIN USART1_MspDeInit 0 */

    /* USER CODE END USART1_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_USART1_CLK_DISABLE();

    /**USART1 GPIO Configuration
    PA9     ------> USART1_TX
    PA10     ------> USART1_RX
    */
    HAL_GPIO_DeInit(GPIOA, GPIO_PIN_9 | GPIO_PIN_10);

    /* USER CODE BEGIN USART1_MspDeInit 1 */

    /* USER CODE END USART1_MspDeInit 1 */
  }
}

/* USER CODE BEGIN 1 */
void USART1_IRQHandler(void)
{
  HAL_UART_IRQHandler(&huart1);
  HAL_UART_Receive_IT(&huart1, (uint8_t *)g_rx_buffer, 1);
}
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
  if (huart->Instance == USART1)
  {
    g_usart1_rx_flag = 1;
  }
}
/* USER CODE END 1 */

main.c

  uint32_t ADC_Value;
  double true_voltage;
  double result_ou;
  double temp;
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    HAL_ADC_Start(&hadc1);
    HAL_ADC_PollForConversion(&hadc1, 50);
    if (HAL_IS_BIT_SET(HAL_ADC_GetState(&hadc1), HAL_ADC_STATE_REG_EOC))
    {
      ADC_Value = HAL_ADC_GetValue(&hadc1);
      true_voltage = ADC_Value * 3.3f / 4096;
      printf("PA0 true Voltage value: %.4f \r\n", true_voltage);
      result_ou = (2000 * true_voltage) / (3.27 - true_voltage);
      printf("result_ou: %.4f\r\n", result_ou);
      temp = 1.0 / (log(result_ou / 10000) / 3435 + 1 / (273.15 + 25)) - 273.15;
      printf("temperature:%.4f\r\n", temp);
    }
    HAL_Delay(1000);
    /* USER CODE BEGIN 3 */
  }