/* USER CODE BEGIN PV */ /* Private variables ---------------------------------------------------------*/ /* USER CODE END PV */

在嵌入式系统开发中，/* USER CODE BEGIN PV */ 和 /* USER CODE END PV */ 是用来放置用户自定义的私有变量的注释块。

在这个注释块内部，用户可以定义和声明私有变量，这些变量将在代码生成器生成的代码中保留。这样做的目的是为了方便用户在代码生成器更新或重新生成代码时，不会丢失他们自己添加的变量。

用户可以在 /* USER CODE BEGIN PV */ 注释块内添加自己需要的私有变量，例如局部变量、全局变量、结构体等。而在 /* USER CODE END PV */ 注释块之后的代码将会由代码生成器生成。

这种方式可以确保用户的自定义代码不会被覆盖或丢失，同时也方便了代码的维护和更新。

相关问题

基于stm32f103c8t6 hc-sr501

基于STM32F103C8T6最小系统板驱动HC-SR501红外人体传感模块的方法如下：

1. 首先，需要在CubeMX中配置PA1引脚为输入模式，并使能GPIOA时钟。

2. 在代码中使用HAL库的GPIO读取PA1引脚的电平状态，即可获取HC-SR501模块输出的人体检测信号。

3. 可以根据读取到的人体检测信号状态来控制其他模块的工作，例如控制LED灯亮灭等。

示例代码如下：

#include "main.h"
#include "stm32f1xx_hal.h"

/* USER CODE BEGIN Includes */

/* USER CODE END Includes */

/* Private variables ---------------------------------------------------------*/
TIM_HandleTypeDef htim2;

/* USER CODE BEGIN PV */
/* Private variables ---------------------------------------------------------*/
GPIO_PinState sensorState;
/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_TIM2_Init(void);

/* USER CODE BEGIN PFP */
/* Private function prototypes -----------------------------------------------*/

/* USER CODE END PFP */

/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

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();
  /* USER CODE BEGIN 2 */
  HAL_TIM_Base_Start(&htim2);
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    sensorState = HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_1);
    if(sensorState == GPIO_PIN_SET)
    {
      // 人体检测到信号
      HAL_GPIO_WritePin(GPIOC, GPIO_PIN_13, GPIO_PIN_SET); // 点亮LED灯
      HAL_Delay(1000); // 延时1秒
    }
    else
    {
      // 人体未检测到信号
      HAL_GPIO_WritePin(GPIOC, GPIO_PIN_13, GPIO_PIN_RESET); // 熄灭LED灯
    }
  /* 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();
  }
}

/**
  * @brief TIM2 Initialization Function
  * @param None
  * @retval None
  */
static void MX_TIM2_Init(void)
{

  /* USER CODE BEGIN TIM2_Init 0 */

  /* USER CODE END TIM2_Init 0 */

  TIM_ClockConfigTypeDef sClockSourceConfig = {0};
  TIM_MasterConfigTypeDef sMasterConfig = {0};

  /* USER CODE BEGIN TIM2_Init 1 */

  /* USER CODE END TIM2_Init 1 */
  htim2.Instance = TIM2;
  htim2.Init.Prescaler = 7199;
  htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim2.Init.Period = 999;
  htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  if (HAL_TIM_Base_Init(&htim2) != HAL_OK)
  {
    Error_Handler();
  }
  sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
  if (HAL_TIM_ConfigClockSource(&htim2, &sClockSourceConfig) != HAL_OK)
  {
    Error_Handler();
  }
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  if (HAL_TIMEx_MasterConfigSynchronization(&htim2, &sMasterConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN TIM2_Init 2 */

  /* USER CODE END TIM2_Init 2 */

}

/**
  * @brief GPIO Initialization Function
  * @param None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOC_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOC, GPIO_PIN_13, GPIO_PIN_RESET);

  /*Configure GPIO pin : PA1 */
  GPIO_InitStruct.Pin = GPIO_PIN_1;
  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /*Configure GPIO pin : PC13 */
  GPIO_InitStruct.Pin = GPIO_PIN_13;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);

}

/**
  * @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 */
  while(1) 
  {
  }
  /* USER CODE END Error_Handler_Debug */
}

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

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

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

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

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

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

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

/**
  * @brief  This function is executed in case of SysTick timer interrupt.
  * @retval None
  */
void SysTick_Handler(void)
{
  /* USER CODE BEGIN SysTick_Handler_Debug */

  /* USER CODE END SysTick_Handler_Debug */
}