【STM32G431RBTx】备战蓝桥杯嵌入式→扩展模块→DHT11
文章目录
-
- 前言
- 一、软件准备
- 二、DHT11
-
- 1.扩展板上模块的原理图以及我们需要配置的元素
- 2.CubeMx的配置步骤
- 3.代码修改以及应用
-
- 方法1.以移植F103驱动包为方法
-
- ①.在工程中添加大赛提供的G431的ds18b20驱动包和F103的DHT11的驱动包
- ②.复制ds18b20的初始化部分到dht11的初始化部分，并修改GPIO的引脚。
- ②.复制ds18b20的改变引脚为输入功能部分到dht11的改变引脚为输入功能部分，并修改GPIO的引脚。
- ③.复制ds18b20的改变引脚为输出功能部分到dht11的改变引脚为输出功能部分，并修改GPIO的引脚。
- ④.修改dht11.c中的dht11_read函数。
- ⑤.修改dht11.c中的延时函数的宏定义。
- ⑥.添加main.h到dht11.h
- ⑦在main.c中编写测试代码
- ⑧将ds18b20驱动从工程中移除(这一步可以不做)
- 方法2.直接使用G431的DHT11例程驱动
-
- ①.在工程中添加大赛提供的G431的DHT11例程中的dht11.c和dht11.h
- ②.在dht11.c中添加u8的宏定义
- ③.在dht11.c中的DHT11_Read_Data函数中修改并添加形参，以及形参赋值的语句
- ④.在dht11.h中添加DHT11_Read_Data函数的新声明，同时将所有u8修改位unsigned char
- ⑤在main.c中编写测试代码
- 方法3.修改大赛提供的驱动包(此方法在2023.6.3更新)
-
- ①.在工程中添加大赛提供的G431的dht11驱动包并修改名称为:dht11.c和dht11.h
- ②.修改头文件如图所示。
- ③.修改C文件中包含头文件名称为dht11.h。
- ④.修改C文件中延时函数的i值(80Mhz修改为16，如果使用其他主频记得以比例替换)。
- ⑤.修改C文件中的接收字节函数。
- ⑥.在C文件中增加复位和检查函数。
- ⑦.在C文件中增加读取温湿度函数。
- ⑧.在main.c文件中增加头文件和变量声明。
- ⑨.在main.c文件中增加测试代码。
- 三、测试代码
-
- 方法一
- 方法二:
- 方法三:
- 四、演示效果
-
- 方法一
- 方法二
- 方法三(偷了个懒方法二三其实现象差不多的)
- 五、工程链接
- 六、总结
前言
我们学完了DS18B20的应用之后，就开始学习DHT11的应用。
DHT11给我的感觉有点怪
第一就是使用时需要占用大量时间(测试了一下，一次读取花了20ms左右，相当于两次按键消抖所花的时间)
第二就是现在官方提供的驱动包只有F103版本的，对于G431只有DHT11的例程，没有专门的驱动包。
第三就是现在比赛中从来就没有考过DHT11的应用(不过为了保险起见还是要做准备)
本篇文章将会讲述如何应用F103的驱动包和G431大赛官方所给的例程来应用DHT11(比赛选一种方法就可以)。
一、软件准备
1、MDK4或者MDK5（可到官网或者其他途径获取，本人使用的是MDK5）
2、Cubemx（可到官网自行下载）
3、安装G4的包（1.2.0，1.3.0以及1.4.0均可）
4、串口调试助手（COM）
二、DHT11
1.扩展板上模块的原理图以及我们需要配置的元素
DHT11部分原理图:
模块在扩展板的布局:
分析:没什么好说的，知道HDQ连接的是PA7引脚就行。
2.CubeMx的配置步骤
RCC配置:略
设置调试接口:设置为Serial Wire
到此配置完成，不需要配置IO口。
生成工程:点击GENERATE CODE生成工程。
3.代码修改以及应用
方法1.以移植F103驱动包为方法
①.在工程中添加大赛提供的G431的ds18b20驱动包和F103的DHT11的驱动包
(我的ds18b20驱动包，是根据ds18b20篇的文章修改过的，其实不修改也没关系，反正后面都要移除掉的)
②.复制ds18b20的初始化部分到dht11的初始化部分，并修改GPIO的引脚。
②.复制ds18b20的改变引脚为输入功能部分到dht11的改变引脚为输入功能部分，并修改GPIO的引脚。
③.复制ds18b20的改变引脚为输出功能部分到dht11的改变引脚为输出功能部分，并修改GPIO的引脚。
④.修改dht11.c中的dht11_read函数。
画红框的部分都要修改为hal库的相应函数(原来的都是标准库函数)
⑤.修改dht11.c中的延时函数的宏定义。
⑥.添加main.h到dht11.h
⑦在main.c中编写测试代码
添加头文件:
参数定义:
液晶初始化:
读取部分:
这里的注释写错了，应该是不能小于108!!!
⑧将ds18b20驱动从工程中移除(这一步可以不做)
至此代码修改和编写已经完成可以下载到板子上进行测试了。
方法2.直接使用G431的DHT11例程驱动
由于目前为止，G431还没有给出专门的DHT11驱动，这里就假设例程中的驱动包是大赛给出的专门的驱动包来使用。
①.在工程中添加大赛提供的G431的DHT11例程中的dht11.c和dht11.h
②.在dht11.c中添加u8的宏定义
③.在dht11.c中的DHT11_Read_Data函数中修改并添加形参，以及形参赋值的语句
④.在dht11.h中添加DHT11_Read_Data函数的新声明，同时将所有u8修改位unsigned char
⑤在main.c中编写测试代码
添加头文件:
液晶初始化:
读取部分:
至此代码修改和编写已经完成可以下载到板子上进行测试了。
方法3.修改大赛提供的驱动包(此方法在2023.6.3更新)
①.在工程中添加大赛提供的G431的dht11驱动包并修改名称为:dht11.c和dht11.h
②.修改头文件如图所示。
③.修改C文件中包含头文件名称为dht11.h。
④.修改C文件中延时函数的i值(80Mhz修改为16，如果使用其他主频记得以比例替换)。
⑤.修改C文件中的接收字节函数。
⑥.在C文件中增加复位和检查函数。
⑦.在C文件中增加读取温湿度函数。
⑧.在main.c文件中增加头文件和变量声明。
⑨.在main.c文件中增加测试代码。
至此代码修改和编写已经完成可以下载到板子上进行测试了。
三、测试代码
代码修改完成之后，添加lcd.h, lcd.c, fonts.h到工程中以方便显示。
方法一
dht11.h:
#ifndef __DHT11_H
#define __DHT11_H
#include "main.h"
void dht11_init (void );
void delay(unsigned int n);
unsigned int dht11_read(void);
#endif
dht11.c
#include "dht11.h"
#define delay_us(X) delayd(X*120/5)
void delayd(unsigned int n)
{
while (n--);
}
void dht11_init (void )
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
/* GPIO Ports Clock Enable */
__HAL_RCC_GPIOA_CLK_ENABLE();
GPIO_InitStruct.Pin = GPIO_PIN_7;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH ;
GPIO_InitStruct.Pull = GPIO_PULLUP ;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
}
void mode_input(void )
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
/* GPIO Ports Clock Enable */
GPIO_InitStruct.Pin = GPIO_PIN_7;
GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
GPIO_InitStruct.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
}
void mode_output(void )
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
GPIO_InitStruct.Pin = GPIO_PIN_7;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
GPIO_InitStruct.Pull = GPIO_NOPULL ;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
}
unsigned int dht11_read(void)
{
int i;
long long val;
int timeout;
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_7, GPIO_PIN_RESET);
delay_us(18000); //pulldown for 18ms
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_7, GPIO_PIN_SET);
delay_us( 20 ); //pullup for 30us
mode_input();
//等待DHT11拉高，80us
timeout = 5000;
while( (! HAL_GPIO_ReadPin (GPIOA, GPIO_PIN_7)) && (timeout > 0) ) timeout--; //wait HIGH
//等待DHT11拉低，80us
timeout = 5000;
while( HAL_GPIO_ReadPin (GPIOA, GPIO_PIN_7) && (timeout > 0) ) timeout-- ; //wait LOW
#define CHECK_TIME 28
for(i=0;i<40;i++)
{
timeout = 5000;
while( (! HAL_GPIO_ReadPin (GPIOA, GPIO_PIN_7)) && (timeout > 0) ) timeout--; //wait HIGH
delay_us(CHECK_TIME);
if ( HAL_GPIO_ReadPin (GPIOA, GPIO_PIN_7) )
{
val=(val<<1)+1;
} else {
val<<=1;
}
timeout = 5000;
while( HAL_GPIO_ReadPin (GPIOA, GPIO_PIN_7) && (timeout > 0) ) timeout-- ; //wait LOW
}
mode_output();
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_7, GPIO_PIN_SET);
if (((val>>32)+(val>>24)+(val>>16)+(val>>8) -val ) & 0xff ) return 0;
else return val>>8;
}
main.h:没有修改故不放出
main.c:
/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file : main.c
* @brief : Main program body
******************************************************************************
* @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 "main.h"
#include "gpio.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "dht11.h"
#include "lcd.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 */
unsigned int DHT11_Value; //read函数接收参数
unsigned int DHT11Tick; //控制每隔一段时间读取的Tick
unsigned char tempi; //温度整数部分
unsigned char tempf; //温度小数部分
unsigned char humii; //湿度整数部分
unsigned char humif; //湿度小数部分
float temp; //温度;
float humi; //湿度
char text[30];
/* 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();
/* USER CODE BEGIN 2 */
LCD_Init();
LCD_Clear(Black);
LCD_SetBackColor(Black);
LCD_SetTextColor(White);
DHT11_Value = dht11_read(); //提前读取防止刚上电一瞬间出现0。
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
if(uwTick - DHT11Tick > 120) //每隔120ms读取一次(不能小于108)
{
DHT11Tick = uwTick;
DHT11_Value = dht11_read();
tempi = DHT11_Value >> 8 & 0xff;
tempf = DHT11_Value >> 0 & 0xff;
humii = DHT11_Value >> 24 & 0xff;
humif = DHT11_Value >> 16 & 0xff;
temp = tempi + tempf / 10.0;
humi = humii + humif / 10.0;
}
sprintf(text, "Temp:%.1f", temp);
LCD_DisplayStringLine(Line0, text);
sprintf(text, "Humi:%.1f", humi);
LCD_DisplayStringLine(Line1, text);
}
/* USER CODE END 3 */
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
/** Configure the main internal regulator output voltage
*/
HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1);
/** 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.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV3;
RCC_OscInitStruct.PLL.PLLN = 20;
RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
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_DIV1;
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 */
方法二:
dht11.h:
#ifndef __DHT11_H
#define __DHT11_H
#include "main.h"
#define DHT11_PIN_PORT GPIOA
#define DHT11_PIN GPIO_PIN_7
#define DHT11_PIN_CLOCK __HAL_RCC_GPIOA_CLK_ENABLE()
#define DHT11_PIN_OUT_H HAL_GPIO_WritePin(DHT11_PIN_PORT, DHT11_PIN, GPIO_PIN_SET)
#define DHT11_PIN_OUT_L HAL_GPIO_WritePin(DHT11_PIN_PORT, DHT11_PIN, GPIO_PIN_RESET)
#define DHT11_PIN_IN HAL_GPIO_ReadPin(DHT11_PIN_PORT, DHT11_PIN)
unsigned char DHT11_Init(void);//初始化DHT11
unsigned char DHT11_Read_Data(unsigned char *tempi, unsigned char *tempf, unsigned char *humii, unsigned char *humif); //读取温湿度
unsigned char DHT11_Read_Byte(void);//读出一个字节
unsigned char DHT11_Read_Bit(void);//读出一个位
unsigned char DHT11_Check(void);//检测是否存在DHT11
void DHT11_Rst(void);//复位DHT11
#endif
dht11.c
#include "dht11.h"
#define u8 unsigned char
#define Delay_us(X) delay((X)*80/5)
void delay(unsigned int n)
{
while(n--);
}
void DHT11_PIN_OUT(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
/**/
GPIO_InitStruct.Pin = DHT11_PIN;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
HAL_GPIO_Init(DHT11_PIN_PORT, &GPIO_InitStruct);
}
void DHT11_PIN_INPUT(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
DHT11_PIN_CLOCK;
/**/
GPIO_InitStruct.Pin = DHT11_PIN;
GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
GPIO_InitStruct.Pull = GPIO_PULLUP;
HAL_GPIO_Init(DHT11_PIN_PORT, &GPIO_InitStruct);
}
//复位DHT11
void DHT11_Rst(void)
{
DHT11_PIN_OUT(); //设置为输出
DHT11_PIN_OUT_L; //低电平
HAL_Delay(20); //拉低至少18ms
DHT11_PIN_OUT_H; //高电平
Delay_us(60); //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
u8 DHT11_Check(void)
{
u8 re = 0;
DHT11_PIN_INPUT(); //设置为输出
while (DHT11_PIN_IN && re < 100) //DHT11会拉低40~80us
{
re++;
Delay_us(1);
};
if(re >= 100)return 1;
else re = 0;
while (!DHT11_PIN_IN && re < 100) //DHT11拉低后会再次拉高40~80us
{
re++;
Delay_us(1);
};
if(re >= 100)return 1;
return 0;
}
//DHT11读取一个位
u8 DHT11_Read_Bit(void)
{
u8 re = 0;
while(DHT11_PIN_IN && re < 110) //等待变为低电平
{
re++;
Delay_us(1);
}
re = 0;
while(!DHT11_PIN_IN && re < 110) //等待变为高电平
{
re++;
Delay_us(1);
}
Delay_us(80);//等待40us
if(DHT11_PIN_IN)return 1;
else return 0;
}
//从DHT11读取一个字节
u8 DHT11_Read_Byte(void)
{
u8 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
u8 DHT11_Read_Data(u8 *tempi, u8 *tempf, u8 *humii, u8 *humif)
{
u8 buf[5];
u8 i;
DHT11_Rst();
if(DHT11_Check() == 0)
{
for(i = 0; i < 5; i++)
{
buf[i] = DHT11_Read_Byte();
}
if((buf[0] + buf[1] + buf[2] + buf[3]) == buf[4])
{
*humii = buf[0];
*humif = buf[1];
*tempi = buf[2];
*tempf = buf[3];
}
}
else return 1;
return 0;
}
//初始化DHT11的IO口，同时检测DHT11的存在
u8 DHT11_Init(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
DHT11_PIN_CLOCK;;
GPIO_InitStruct.Pin = DHT11_PIN;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
HAL_GPIO_Init(DHT11_PIN_PORT, &GPIO_InitStruct);
DHT11_Rst();
return DHT11_Check();
}
main.h:没有修改故不放出
main.c:
/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file : main.c
* @brief : Main program body
******************************************************************************
* @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 "main.h"
#include "gpio.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "lcd.h"
#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 */
unsigned char tempi;
unsigned char humii;
unsigned char tempf;
unsigned char humif;
float temp;
float humi;
char text[30];
/* 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();
/* USER CODE BEGIN 2 */
LCD_Init();
LCD_Clear(Black);
LCD_SetBackColor(Black);
LCD_SetTextColor(White);
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
DHT11_Read_Data(&tempi, &tempf, &humii, &humif); //可以不用每隔一段时间采集一次，
//但是不能放入中断执行
temp = tempi + tempf / 10.0;
humi = humii + humif / 10.0;
sprintf(text, "temp:%.2fhumi:%.2f", temp, humi);
LCD_DisplayStringLine(Line0, text);
}
/* USER CODE END 3 */
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
/** Configure the main internal regulator output voltage
*/
HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1);
/** 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.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV3;
RCC_OscInitStruct.PLL.PLLN = 20;
RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
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_DIV1;
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 */
方法三:
dht11.h:
#ifndef __DHT11_H
#define __DHT11_H
#include "main.h"
#define HDQ GPIO_PIN_7
typedef struct {
uint8_t humidity_high;
uint8_t humidity_low;
uint8_t temperature_high;
uint8_t temperature_low;
}dht11Data;
void dht11Init(void);
void dht11Read(void);
#endif
dht11.c:
#include "dht11.h"
dht11Data dht11;
//
static void usDelay(uint32_t us)
{
uint16_t i = 0;
while(us--){
i = 16; /******************************/
while(i--);
}
}
//
void outDQ(uint8_t i)
{
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.Pin = HDQ;
GPIO_InitStructure.Speed = GPIO_SPEED_FREQ_HIGH;
GPIO_InitStructure.Mode = GPIO_MODE_OUTPUT_PP;
HAL_GPIO_Init(GPIOA, &GPIO_InitStructure);
if(!i)
HAL_GPIO_WritePin(GPIOA, HDQ, GPIO_PIN_RESET);
else
HAL_GPIO_WritePin(GPIOA, HDQ, GPIO_PIN_SET);
}
//
void inDQ(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.Pin = HDQ;
GPIO_InitStructure.Mode = GPIO_MODE_INPUT;
GPIO_InitStructure.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOA, &GPIO_InitStructure);
}
//
void dht11Init(void)
{
__HAL_RCC_GPIOA_CLK_ENABLE();
outDQ(1);
}
//
uint8_t recData(void)
{
uint8_t i,temp=0,j=220;
for(i=0; i<8; i++){
while(HAL_GPIO_ReadPin(GPIOA,HDQ)); /*****************/
while(!HAL_GPIO_ReadPin(GPIOA,HDQ));
usDelay(40);
if(HAL_GPIO_ReadPin(GPIOA,HDQ))
{
temp=(temp<<1)|1;
while(HAL_GPIO_ReadPin(GPIOA,HDQ)&&(j--));
}
else
{
temp=(temp<<1)|0;
}
}
return temp;
}
void dht11_rst(void)
{
outDQ(0);
HAL_Delay(20); //拉低至少18ms
outDQ(1);
usDelay(60); //主机拉高20-40us
}
unsigned char dht11_check(void)
{
unsigned char re = 0;
inDQ(); //设置为输入
while(HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_7) && re < 100) //DHT11会拉低40-80us
{
re++;
usDelay(1);
}
if(re >= 100) return 1;
else re = 0;
while(!HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_7) && re < 100) //DHT11拉低后会再拉高40-80us
{
re++;
usDelay(1);
}
if(re >= 100) return 1;
else return 0;
}
void dht11Read(void)
{
unsigned char buf[5];
dht11_rst();
if(dht11_check() == 0)
{
for(unsigned char i = 0; i < 5; i++)
{
buf[i] = recData();
}
if(buf[0] + buf[1] + buf[2] + buf[3] == buf[4])
{
dht11.humidity_high = buf[0];
dht11.humidity_low = buf[1];
dht11.temperature_high = buf[2];
dht11.temperature_low = buf[3];
}
}
}
main.h:没有修改故不放出
main.c:
/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file : main.c
* @brief : Main program body
******************************************************************************
* @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 "main.h"
#include "gpio.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "dht11.h"
#include "lcd.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 */
char text[30];
extern dht11Data dht11;
/* 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();
/* USER CODE BEGIN 2 */
LCD_Init();
LCD_Clear(Black);
LCD_SetBackColor(Black);
LCD_SetTextColor(White);
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
dht11Read();
sprintf(text, "humi:%.2f", dht11.humidity_high + dht11.humidity_low / 10.0);
LCD_DisplayStringLine(Line0, text);
sprintf(text, "temp:%.2f", dht11.temperature_high + dht11.temperature_low / 10.0);
LCD_DisplayStringLine(Line1, text);
}
/* USER CODE END 3 */
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
/** Configure the main internal regulator output voltage
*/
HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1);
/** 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.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV3;
RCC_OscInitStruct.PLL.PLLN = 20;
RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
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_DIV1;
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 */
四、演示效果
方法一
方法二
方法三(偷了个懒方法二三其实现象差不多的)
五、工程链接
DHT11模块方法1工程
DHT11模块方法2工程
DHT11模块方法3工程
六、总结
以上就是DHT11的配置过程，测试代码以及测试效果
以往的扩展板模块:
【STM32G431RBTx】备战蓝桥杯嵌入式→扩展模块→SEG
【STM32G431RBTx】备战蓝桥杯嵌入式→扩展模块→双路ADC/AO1, AO2
【STM32G431RBTx】备战蓝桥杯嵌入式→扩展模块→光敏电阻/TRAO, TRAO
【STM32G431RBTx】备战蓝桥杯嵌入式→扩展模块→AKEY
【STM32G431RBTx】备战蓝桥杯嵌入式→扩展模块→DS18B20