stm32f103zet6_串口实现-DHT11-tim1(定时)

1思路

1打开时钟

1.1使用定时器实现us级的计时

1.2在打开串口

1,3在DHT11驱动中修改引脚

stm32cudeMX 配置

1打开时钟

2打开串口

3打开tim1(定时器)

4生成代码

代码设置

1导入DHT11库(tim.h是定时器的文件系统自动生成的)

DHT11.c

#include "dht11.h"
#include "tim.h"
 
void DHT11_IO_IN(void)
{
	GPIO_InitTypeDef GPIO_InitStructure;
	
	GPIO_InitStructure.Pin = GPIO_PIN_1;
	GPIO_InitStructure.Mode = GPIO_MODE_INPUT;
	HAL_GPIO_Init(GPIOA,&GPIO_InitStructure);
}
 
void DHT11_IO_OUT(void)
{
	GPIO_InitTypeDef GPIO_InitStructure;
	GPIO_InitStructure.Pin = GPIO_PIN_1;
	GPIO_InitStructure.Mode = GPIO_MODE_OUTPUT_PP;
	GPIO_InitStructure.Speed = GPIO_SPEED_FREQ_HIGH;
	HAL_GPIO_Init(GPIOA,&GPIO_InitStructure);
}
 
 
//复位DHT11
void DHT11_Rst(void)	   
{                 
	DHT11_IO_OUT(); 	//设置为输出
	DHT11_DQ_OUT_LOW; 	//拉低DQ
	HAL_Delay(20);    	//拉低至少18ms
	DHT11_DQ_OUT_HIGH; 	//DQ=1 
	delay_us(30);     	//主机拉高20~40us
}
 
//等待DHT11的回应
//返回1:未检测到DHT11的存在
//返回0:存在
uint8_t DHT11_Check(void) 	   
{   
	uint8_t retry=0;
	DHT11_IO_IN();      //设置为输出	 
	while (DHT11_DQ_IN&&retry<100)//DHT11会拉低40~80us
	{
		retry++;
		delay_us(1);
	};	 
	if(retry>=100)return 1;
	else retry=0;
	while (!DHT11_DQ_IN&&retry<100)//DHT11拉低后会再次拉高40~80us
	{
		retry++;
		delay_us(1);
	};
	if(retry>=100)return 1;	    
	return 0;
}
 
//从DHT11读取一个位
//返回值：1/0
uint8_t DHT11_Read_Bit(void) 			 
{
 	uint8_t retry=0;
	while(DHT11_DQ_IN&&retry<100)//等待变为低电平
	{
		retry++;
		delay_us(1);
	}
	retry=0;
	while(!DHT11_DQ_IN&&retry<100)//等待变高电平
	{
		retry++;
		delay_us(1);
	}
	delay_us(40);//等待40us
	if(DHT11_DQ_IN)return 1;
	else return 0;		   
}
 
//从DHT11读取一个字节
//返回值：读到的数据
uint8_t DHT11_Read_Byte(void)    
{        
	uint8_t i,dat;
	dat=0;
	for (i=0;i<8;i++) 
	{
   		dat<<=1; 
	    dat|=DHT11_Read_Bit();
    }						    
    return dat;
}
 
//从DHT11读取一次数据
//temp:温度值(范围:0~50°)
//humi:湿度值(范围:20%~90%)
//返回值：0,正常;1,读取失败
uint8_t DHT11_Read_Data(uint16_t *temp,uint16_t *humi)    
{        
 	uint8_t buf[5];
	uint8_t i;
	DHT11_Rst();
	if(DHT11_Check()==0)
	{
		for(i=0;i<5;i++)//读取40位数据
		{
			buf[i]=DHT11_Read_Byte();
		}
		if((buf[0]+buf[1]+buf[2]+buf[3])==buf[4])
		{
			*humi=(buf[0]<<8) + buf[1];
			*temp=(buf[2]<<8) + buf[3];
		}
	}else return 1;
	return 0;	    
}
 
//初始化DHT11的IO口 DQ 同时检测DHT11的存在
//返回1:不存在
//返回0:存在     	 
uint8_t DHT11_Init(void)
{ 
  DHT11_Rst();
	return DHT11_Check();
}

DHT11.h

#ifndef __DHT11_H__
#define __DHT11_H__
#include "main.h"
#define DHT11_DQ_OUT_HIGH HAL_GPIO_WritePin(GPIOA,GPIO_PIN_1,GPIO_PIN_SET)
#define DHT11_DQ_OUT_LOW 	HAL_GPIO_WritePin(GPIOA,GPIO_PIN_1,GPIO_PIN_RESET)
#define DHT11_DQ_IN	 HAL_GPIO_ReadPin(GPIOA,GPIO_PIN_1)
 
//IO方向设置
void DS18B20_IO_IN(void);
void DS18B20_IO_OUT(void);
	
uint8_t DHT11_Init(void);//初始化DHT11
uint8_t DHT11_Read_Data(uint16_t *temp,uint16_t *humi);//读取温湿度
uint8_t DHT11_Read_Byte(void);//读出一个字节
uint8_t DHT11_Read_Bit(void);//读出一个位
uint8_t DHT11_Check(void);//检测是否存在DHT11
void DHT11_Rst(void);//复位DHT11  
 
#endif

2在定时文件中添加计时

利用定时实现数

在tim.c中末尾添加如下函数利用定时其2实现的

/* USER CODE BEGIN 1 */
void delay_us(uint16_t us)
{
    uint16_t differ = 0xffff-us-5;                
    __HAL_TIM_SET_COUNTER(&htim2,differ);    
    HAL_TIM_Base_Start(&htim2);        
    
    while(differ < 0xffff-5)
    {   
        differ = __HAL_TIM_GET_COUNTER(&htim2);     
    }
    HAL_TIM_Base_Stop(&htim2);
}

void delay_ms(uint16_t ms){
		for(int i=0;i<ms;i++){
				delay_us(1000);
		}
}

void delay_s(uint16_t s){
		for(int i=0;i<s;i++){
				delay_ms(1000);
		}
}
/* USER CODE END 1 */

tim.h

/* USER CODE BEGIN Includes */
void delay_us(uint16_t us);
void delay_ms(uint16_t ms);
void delay_s(uint16_t s);
/* USER CODE END Includes */

3调用DHT11函数

添加库文件

/* USER CODE BEGIN Includes */
#include "DHT11.h"
#include "stdio.h"
/* USER CODE END Includes */

main函数

int main(void)
{

  /* USER CODE BEGIN 1 */

  /* USER CODE END 1 */

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_TIM2_Init();
  MX_USART1_UART_Init();
  /* USER CODE BEGIN 2 */
	uint16_t wen_du;//温度
	uint16_t shi_du;//湿度
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
		if(DHT11_Init()){//判断是否有DHT11
			uint8_t data[]={"没有检测到DHT11"};
			HAL_UART_Transmit(&huart1,data,sizeof(data),20);
		}else{
			//采集数据
			DHT11_Init();
			DHT11_Read_Data(&wen_du,&shi_du);
			//存储数据
			char DHT11_data1[2];
			char DHT11_data2[2];
			char DHT11_data3[2];
			char DHT11_data4[2];
			//数据转换//转换成字符
			sprintf(DHT11_data1,"%d",(wen_du>>8));//温度高8位
			sprintf(DHT11_data2,"%d",(wen_du&0xff));//温度低8位
			sprintf(DHT11_data3,"%d",(shi_du>>8));//湿度高8位
			sprintf(DHT11_data4,"%d",(shi_du&0xff));//湿度低8位
			//符号
			uint8_t wen_du_zi[]={"温度为："};
			uint8_t shi_du_zi[]={"湿度为："};
			uint8_t dian[]={"."};
			uint8_t bai_fen_hao[]={"%"};
			uint8_t wen_du_fu[]={"°C"};
			//显示数据
			HAL_UART_Transmit(&huart1,wen_du_zi,sizeof(wen_du_zi),20);//温度为
			HAL_UART_Transmit(&huart1,(uint8_t*)DHT11_data1,sizeof(DHT11_data1),20);//整数
			HAL_UART_Transmit(&huart1,dian,1,20);
			HAL_UART_Transmit(&huart1,(uint8_t*)DHT11_data2,sizeof(DHT11_data2),20);//小数
			HAL_UART_Transmit(&huart1,wen_du_fu,4,20);//符号
			delay_s(1);
			HAL_UART_Transmit(&huart1,shi_du_zi,sizeof(shi_du_zi),20);//湿度为
			HAL_UART_Transmit(&huart1,(uint8_t*)DHT11_data3,sizeof(DHT11_data3),20);//整数
			HAL_UART_Transmit(&huart1,dian,1,20);
			HAL_UART_Transmit(&huart1,(uint8_t*)DHT11_data4,sizeof(DHT11_data4),20);//小数
			HAL_UART_Transmit(&huart1,bai_fen_hao,1,20);//符号
		}
		
		delay_s(1);
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}

main.h文件

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2024 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 "main.h"
#include "tim.h"
#include "usart.h"
#include "gpio.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "DHT11.h"
#include "stdio.h"
/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */

/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/

/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{

  /* USER CODE BEGIN 1 */

  /* USER CODE END 1 */

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_TIM2_Init();
  MX_USART1_UART_Init();
  /* USER CODE BEGIN 2 */
	uint16_t wen_du;//温度
	uint16_t shi_du;//湿度
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
		if(DHT11_Init()){//判断是否有DHT11
			uint8_t data[]={"没有检测到DHT11"};
			HAL_UART_Transmit(&huart1,data,sizeof(data),20);
		}else{
			//采集数据
			DHT11_Init();
			DHT11_Read_Data(&wen_du,&shi_du);
			//存储数据
			char DHT11_data1[2];
			char DHT11_data2[2];
			char DHT11_data3[2];
			char DHT11_data4[2];
			//数据转换//转换成字符
			sprintf(DHT11_data1,"%d",(wen_du>>8));//温度高8位
			sprintf(DHT11_data2,"%d",(wen_du&0xff));//温度低8位
			sprintf(DHT11_data3,"%d",(shi_du>>8));//湿度高8位
			sprintf(DHT11_data4,"%d",(shi_du&0xff));//湿度低8位
			//符号
			uint8_t wen_du_zi[]={"温度为："};
			uint8_t shi_du_zi[]={"湿度为："};
			uint8_t dian[]={"."};
			uint8_t bai_fen_hao[]={"%"};
			uint8_t wen_du_fu[]={"°C"};
			//显示数据
			HAL_UART_Transmit(&huart1,wen_du_zi,sizeof(wen_du_zi),20);//温度为
			HAL_UART_Transmit(&huart1,(uint8_t*)DHT11_data1,sizeof(DHT11_data1),20);//整数
			HAL_UART_Transmit(&huart1,dian,1,20);
			HAL_UART_Transmit(&huart1,(uint8_t*)DHT11_data2,sizeof(DHT11_data2),20);//小数
			HAL_UART_Transmit(&huart1,wen_du_fu,4,20);//符号
			delay_s(1);
			HAL_UART_Transmit(&huart1,shi_du_zi,sizeof(shi_du_zi),20);//湿度为
			HAL_UART_Transmit(&huart1,(uint8_t*)DHT11_data3,sizeof(DHT11_data3),20);//整数
			HAL_UART_Transmit(&huart1,dian,1,20);
			HAL_UART_Transmit(&huart1,(uint8_t*)DHT11_data4,sizeof(DHT11_data4),20);//小数
			HAL_UART_Transmit(&huart1,bai_fen_hao,1,20);//符号
		}
		
		delay_s(1);
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
  {
    Error_Handler();
  }
}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
  __disable_irq();
  while (1)
  {
  }
  /* USER CODE END Error_Handler_Debug */
}

#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 CODE BEGIN 6 */
  /* 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) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

本人的下载资源中有完整的项目（免费下载）