STM32L476RG：低功耗应用的理想选择—一个基于HAL库的温湿度采集系统

#include "main.h"



/* Private function prototypes */

void SystemClock_Config(void);

static void MX_GPIO_Init(void);

static void MX_USART1_UART_Init(void);

static void MX_I2C1_Init(void);

void DHT22_Read(void);

void USART_Printf(const char *str);



/* Global variables */

UART_HandleTypeDef huart1;

I2C_HandleTypeDef hi2c1;



int main(void)

{

    /* MCU初始化 */

    HAL_Init();



    /* 配置系统时钟 */

    SystemClock_Config();



    /* 初始化外设 */

    MX_GPIO_Init();

    MX_USART1_UART_Init();

    MX_I2C1_Init();



    /* 无限循环 */

    while (1)

    {

        /* 读取温湿度传感器数据 */

        DHT22_Read();



        /* 延时1秒 */

        HAL_Delay(1000);

    }

}



/* 温湿度传感器读取函数 */

void DHT22_Read(void)

{

    uint8_t data[5];



    // 模拟读取DHT22数据

    if (HAL_I2C_Master_Transmit(&hi2c1, (0x5C << 1), data, sizeof(data), HAL_MAX_DELAY) == HAL_OK)

    {

        // 模拟传感器返回的温湿度数据

        float temperature = (float)(data[0] << 8 | data[1]) / 10.0;

        float humidity = (float)(data[2] << 8 | data[3]) / 10.0;



        /* 格式化输出温湿度数据 */

        char msg[50];

        snprintf(msg, sizeof(msg), "Temperature: %.2f C, Humidity: %.2f %%\r\n", temperature, humidity);

        USART_Printf(msg);

    }

    else

    {

        USART_Printf("I2C communication error\r\n");

    }

}



/* 串口输出函数 */

void USART_Printf(const char *str)

{

    HAL_UART_Transmit(&huart1, (uint8_t *)str, strlen(str), HAL_MAX_DELAY);

}



/* 系统时钟配置函数 */

void SystemClock_Config(void)

{

    RCC_OscInitTypeDef RCC_OscInitStruct = {0};

    RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};



    /* 配置HSE外部振荡器 */

    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 = 8;

    RCC_OscInitStruct.PLL.PLLN = 160;

    RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV4;

    RCC_OscInitStruct.PLL.PLLQ = 4;

    HAL_RCC_OscConfig(&RCC_OscInitStruct);



    /* 配置系统时钟 */

    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_DIV2;

    RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

    HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4);

}



/* GPIO初始化函数 */

static void MX_GPIO_Init(void)

{

    __HAL_RCC_GPIOA_CLK_ENABLE();

}



/* USART1初始化函数 */

static void MX_USART1_UART_Init(void)

{

    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;

    HAL_UART_Init(&huart1);

}



/* I2C1初始化函数 */

static void MX_I2C1_Init(void)

{

    hi2c1.Instance = I2C1;

    hi2c1.Init.Timing = 0x10909CEC;

    hi2c1.Init.OwnAddress1 = 0;

    hi2c1.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;

    hi2c1.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;

    hi2c1.Init.OwnAddress2 = 0;

    hi2c1.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;

    hi2c1.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;

    HAL_I2C_Init(&hi2c1);

}