stm32f103c8t6驱动二氧化碳传感器

### STM32F103C8T6 驱动二氧化碳传感器示例代码和教程 #### 使用STM32F103C8T6驱动SCD4X二氧化碳传感器的概述 为了实现STM32F103C8T6微控制器与Sensirion SCD4X系列高精度二氧化碳、湿度及温度传感器之间的通信，可以采用USART1接口以9600的波特率进行数据交换[^1]。 #### 硬件连接说明 硬件连接方式如下： - **IIC 接口**: - `SCL` 连接到 PB6 - `SDA` 连接到 PB7 - **USART1 接口**: - 波特率为9600 - 下载工具：JLink用于将程序下载到系统板上[^4] #### 初始化配置 初始化过程中需确保正确配置GPIO端口以及开启相应的外设时钟。对于SCD4X传感器来说，还需要发送特定命令来启动连续测量模式。 ```c #include "stm32f1xx_hal.h" // 定义 I2C 地址 #define SCD4X_I2C_ADDRESS (uint16_t)(0x62) // 创建 I2C 句柄结构体实例 I2C_HandleTypeDef hi2c1; void SystemClock_Config(void); static void MX_GPIO_Init(void); static void MX_I2C1_Init(void); int main(void) { HAL_Init(); SystemClock_Config(); MX_GPIO_Init(); MX_I2C1_Init(); uint16_t data[2]; // 启动持续测量模式 uint8_t start_periodic_measurement_cmd[] = {0x21, 0xB1}; HAL_I2C_Master_Transmit(&hi2c1, SCD4X_I2C_ADDRESS << 1, start_periodic_measurement_cmd, sizeof(start_periodic_measurement_cmd), HAL_MAX_DELAY); while (1) { // 获取 CO2 测量值 uint8_t read_data_cmd[] = {0xEC, 0x05}; HAL_I2C_Master_Transmit(&hi2c1, SCD4X_I2C_ADDRESS << 1, read_data_cmd, sizeof(read_data_cmd), HAL_MAX_DELAY); HAL_Delay(1); // 添加短延时 HAL_I2C_Master_Receive(&hi2c1, SCD4X_I2C_ADDRESS << 1, (uint8_t *)data, sizeof(data), HAL_MAX_DELAY); float co2_ppm = ((float)data[0] * 256.0 + (float)data[1]); printf("CO2 Concentration: %.2f ppm\n", co2_ppm); HAL_Delay(5000); // 每隔五秒打印一次结果 } } /** * @brief System Clock Configuration */ void SystemClock_Config(void){ RCC_OscInitTypeDef RCC_OscInitStruct = {0}; RCC_ClkInitTypeDef RCC_ClkInitStruct = {0}; /* Initializes the CPU, AHB and APB busses clocks */ 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.PLLMUL = RCC_PLL_MUL9; if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) { Error_Handler(); } /* Initializes the CPU, AHB and APB busses 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(); } } /** * @brief GPIO Initialization Function */ static void MX_GPIO_Init(void) { __HAL_RCC_GPIOD_CLK_ENABLE(); /* Configure PD2 as output push-pull mode to drive LED */ GPIO_InitTypeDef GPIO_InitStruct = {0}; GPIO_InitStruct.Pin = GPIO_PIN_2; GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP; GPIO_InitStruct.Pull = GPIO_NOPULL; GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW; HAL_GPIO_Init(GPIOD, &GPIO_InitStruct); } /** * @brief I2C1 Initialization Function */ static void MX_I2C1_Init(void) { hi2c1.Instance = I2C1; hi2c1.Init.Timing = 0x20909CEC; 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; if (HAL_I2C_Init(&hi2c1) != HAL_OK) { Error_Handler(); } } ``` 上述代码展示了如何使用STM32CubeMX生成的基础框架，在此基础上增加了针对SCD4X传感器的操作指令。通过这种方式能够有效地获取并处理来自该设备的数据流。