基于stm32的mq-7，gp2y1014au传感器检测一氧化碳，pm2.5浓度装置的代码，要有阈值报警模块

以下是基于STM32的MQ-7、GP2Y1014AU传感器检测一氧化碳和PM2.5浓度的代码，同时包含阈值报警模块。在代码中，使用了ADC采集传感器数据，并通过串口输出数据和报警信息。

#include "main.h"
#include "stdio.h"

/* Private variables ---------------------------------------------------------*/
ADC_HandleTypeDef hadc1;
UART_HandleTypeDef huart1;

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_USART1_UART_Init(void);
static void MX_ADC1_Init(void);

/* Private user variables ----------------------------------------------------*/
float CO_concentration = 0.0;
float PM25_concentration = 0.0;
float CO_threshold = 50.0; // 设定CO阈值为50 ppm
float PM25_threshold = 75.0; // 设定PM2.5阈值为75 ug/m3

/* Private user functions ----------------------------------------------------*/
void UART_Print(char *str) {
  HAL_UART_Transmit(&huart1, (uint8_t*) str, strlen(str), HAL_MAX_DELAY);
}

void UART_Println(char *str) {
  UART_Print(str);
  UART_Print("\r\n");
}

/* Main function -------------------------------------------------------------*/
int main(void) {
  /* MCU Configuration--------------------------------------------------------*/
  HAL_Init();
  SystemClock_Config();
  MX_GPIO_Init();
  MX_USART1_UART_Init();
  MX_ADC1_Init();

  /* Infinite loop -----------------------------------------------------------*/
  while (1) {
    // 采集CO浓度
    HAL_ADC_Start(&hadc1);
    HAL_ADC_PollForConversion(&hadc1, HAL_MAX_DELAY);
    uint16_t CO_adc_value = HAL_ADC_GetValue(&hadc1);
    CO_concentration = (float) CO_adc_value / 4096 * 5000 / 200; // 5000 mV的参考电压，200 ppm/V的灵敏度
    char CO_concentration_str[10];
    sprintf(CO_concentration_str, "%.2f", CO_concentration);

    // 采集PM2.5浓度
    // ...

    // 判断是否超过阈值
    if (CO_concentration > CO_threshold) {
      UART_Println("CO concentration exceeds threshold!");
      // 发送报警信息
      // ...
    }

    if (PM25_concentration > PM25_threshold) {
      UART_Println("PM2.5 concentration exceeds threshold!");
      // 发送报警信息
      // ...
    }

    // 输出采集的数据
    char data_str[50];
    sprintf(data_str, "CO: %s ppm, PM2.5: %s ug/m3", CO_concentration_str, "N/A");
    UART_Println(data_str);

    HAL_Delay(1000);
  }
}

/* ADC1 Initialization Function */
static void MX_ADC1_Init(void) {
  ADC_ChannelConfTypeDef sConfig = {0};

  /* Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion) */
  hadc1.Instance = ADC1;
  hadc1.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV4;
  hadc1.Init.Resolution = ADC_RESOLUTION_12B;
  hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
  hadc1.Init.ScanConvMode = DISABLE;
  hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
  hadc1.Init.LowPowerAutoWait = DISABLE;
  hadc1.Init.ContinuousConvMode = DISABLE;
  hadc1.Init.NbrOfConversion = 1;
  hadc1.Init.DiscontinuousConvMode = DISABLE;
  hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
  hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
  hadc1.Init.DMAContinuousRequests = DISABLE;
  hadc1.Init.Overrun = ADC_OVR_DATA_OVERWRITTEN;
  hadc1.Init.OversamplingMode = DISABLE;
  if (HAL_ADC_Init(&hadc1) != HAL_OK) {
    Error_Handler();
  }

  /* Configure the selected ADC channel */
  sConfig.Channel = ADC_CHANNEL_0;
  sConfig.Rank = ADC_REGULAR_RANK_1;
  sConfig.SamplingTime = ADC_SAMPLETIME_239CYCLES_5;
  sConfig.SingleDiff = ADC_SINGLE_ENDED;
  sConfig.OffsetNumber = ADC_OFFSET_NONE;
  sConfig.Offset = 0;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK) {
    Error_Handler();
  }
}

/* USART1 Initialization Function */
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;
  if (HAL_UART_Init(&huart1) != HAL_OK) {
    Error_Handler();
  }
}

/* GPIO Initialization Function */
static void MX_GPIO_Init(void) {
  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOA_CLK_ENABLE();

  /* Configure GPIO pin : PA5 */
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  GPIO_InitStruct.Pin = GPIO_PIN_5;
  GPIO_InitStruct.Mode = GPIO_MODE_ANALOG_ADC_CONTROL;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
}

/* System Clock Configuration */
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_HSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
  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_HSI;
  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_0) != HAL_OK) {
    Error_Handler();
  }
}

/* This function is executed in case of error occurrence. */
void Error_Handler(void) {
  /* User code can be inserted here to handle errors */
  while (1) {
  }
}