C Low-Level I/O functions

最新推荐文章于 2023-09-08 23:07:50 发布
原创 最新推荐文章于 2023-09-08 23:07:50 发布 · 2.4k 阅读 · 1 ·
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文章标签：

#c #descriptor #stream #parsing #io #buffer

本文探讨了低级文件I/O的重要性和应用场景，特别是在处理大量二进制数据、直接使用文件描述符进行操作以及在子进程中传递描述符时的优势。文章还列举了一些仅能在低级I/O中实现的功能，并提供了相关资源链接。

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以前在看别人的很多代码时候，经常看到低级的C语言文件I/O函数。不过自己却从来还没有用到过低级的I/O函数。在纯C里面就f开头的stream用得多。这次要做SIDB在底层实现数据库存储文件，就得必须依靠低级文件I/O才能做了。因为低级文件I/O提供了某些功能，而高级文件I/O函数中没有。

  这是我在网上找到为什么要使用低级IO的一些原因:

摘自: http://www.linuxtopia.org/online_books/programming_books/gnu_libc_guide/Low_002dLevel-I_002fO.html

  • For reading binary files in large chunks.
  • For reading an entire file into core before parsing it.
  • To perform operations other than data transfer, which can only be done with a descriptor. (You can use fileno to get the descriptor corresponding to a stream.)
  • To pass descriptors to a child process. (The child can create its own stream to use a descriptor that it inherits, but cannot inherit a stream directly.)

 

下面是我总结一些文件必须使用Low-Level的I/O函数的原因:

1. 低级IO没有提供buffer,而我们使用f开头以及C++等很多文件操作，都是带缓冲的。
2. 低级IO在功能上更加强大。据我所知，诸如_filelength和_chsize，获取文件的长度和改变文件的长度，这两个函数，在高级文件IO中是找不到的。

关于Low-Level的文件I/O资料，可以在下面网址找到：
http://www.chemie.fu-berlin.de/chemnet/use/info/libc/libc_8.html
http://www.gnu.org/software/libc/manual/html_node/Low_002dLevel-I_002fO.html
http://www.informit.com/guides/content.aspx?g=cplusplus&seqNum=208
http://www.thinkage.ca/english/gcos/expl/c/lib/open.html

 
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“/* USER CODE BEGIN Header */ /** ****************************************************************************** * @file : main.c * @brief : Main program body ****************************************************************************** * @attention * * Copyright (c) 2025 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 */ /* 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 */ /* 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 */ //HAL_GPIO_WritePin(LED_GPIO_Port,LED_Pin,GPIO_PIN_RESET); /* USER CODE END 2 */ /* Infinite loop */ /* USER CODE BEGIN WHILE */ while (1) { /* USER CODE END WHILE */ HAL_GPIO_WritePin(LED_GPIO_Port,LED_Pin,GPIO_PIN_RESET); /* USER CODE BEGIN 3 */ } /* USER CODE END 3 */ } /** * @brief System Clock Configuration * @retval None */ void SystemClock_Config(void) { RCC_OscInitTypeDef RCC_OscInitStruct = {0}; 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} } /* 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 */ ”“/* USER CODE BEGIN Header */ /** ****************************************************************************** * @file gpio.c * @brief This file provides code for the configuration * of all used GPIO pins. ****************************************************************************** * @attention * * Copyright (c) 2025 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 "gpio.h" /* USER CODE BEGIN 0 */ /* USER CODE END 0 */ /*----------------------------------------------------------------------------*/ /* Configure GPIO */ /*----------------------------------------------------------------------------*/ /* USER CODE BEGIN 1 */ /* USER CODE END 1 */ /** Configure pins as * Analog * Input * Output * EVENT_OUT * EXTI */ void MX_GPIO_Init(void) { GPIO_InitTypeDef GPIO_InitStruct = {0}; 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/* USER CODE BEGIN EFP */ /* USER CODE END EFP */ /* Private defines -----------------------------------------------------------*/ #define LED_Pin GPIO_PIN_5 #define LED_GPIO_Port GPIOB /* USER CODE BEGIN Private defines */ /* USER CODE END Private defines */ #ifdef __cplusplus } #endif #endif /* __MAIN_H */ ”这是我的代码
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```c #include "stm32f10x.h" int main(void) { // 必须首先使能AFIO时钟 RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE); // 禁用JTAG（释放PB3、PB4、PB5），但保留SWD（用于调试） GPIO_...
main.c：“/* USER CODE END Header */ /* Includes ------------------------------------------------------------------*/ #include "main.h" #include "tim.h" #include "usart.h" #include "gpio.h" /* Private includes ----------------------------------------------------------*/ /* USER CODE BEGIN Includes */ /* 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 */ /* 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 */ 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(); MX_USART1_UART_Init(); /* USER CODE BEGIN 2 */ /* USER CODE END 2 */ /* Infinite loop */ /* USER CODE BEGIN WHILE */ while (1) { /* USER CODE END WHILE */ /* USER CODE BEGIN 3 */ } /* USER CODE END 3 */ } 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(); } } /* USER CODE BEGIN 4 */ /* USER CODE END 4 */ 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 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 */” gpio.c：“/* Includes ------------------------------------------------------------------*/ #include "gpio.h" /* USER CODE BEGIN 0 */ /* USER CODE END 0 */ /*----------------------------------------------------------------------------*/ /* Configure GPIO */ /*----------------------------------------------------------------------------*/ /* USER CODE BEGIN 1 */ /* USER CODE END 1 */ void MX_GPIO_Init(void) { GPIO_InitTypeDef GPIO_InitStruct = {0}; /* GPIO Ports Clock Enable */ __HAL_RCC_GPIOC_CLK_ENABLE(); __HAL_RCC_GPIOA_CLK_ENABLE(); __HAL_RCC_GPIOB_CLK_ENABLE(); /*Configure GPIO pin Output Level */ HAL_GPIO_WritePin(GPIOC, GPIO_PIN_0|GPIO_PIN_1, GPIO_PIN_RESET); /*Configure GPIO pins : PC0 PC1 */ GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1; GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP; GPIO_InitStruct.Pull = GPIO_NOPULL; GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH; HAL_GPIO_Init(GPIOC, &GPIO_InitStruct); } /* USER CODE BEGIN 2 */ /* USER CODE END 2 */ ” tim.c：“/* Includes ------------------------------------------------------------------*/ #include "tim.h" /* USER CODE BEGIN 0 */ /* USER CODE END 0 */ TIM_HandleTypeDef htim2; /* TIM2 init function */ void MX_TIM2_Init(void) { /* USER CODE BEGIN TIM2_Init 0 */ /* USER CODE END TIM2_Init 0 */ TIM_MasterConfigTypeDef sMasterConfig = {0}; TIM_OC_InitTypeDef sConfigOC = {0}; /* USER CODE BEGIN TIM2_Init 1 */ /* USER CODE END TIM2_Init 1 */ htim2.Instance = TIM2; htim2.Init.Prescaler = 71; htim2.Init.CounterMode = TIM_COUNTERMODE_UP; htim2.Init.Period = 1000; htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1; htim2.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE; if (HAL_TIM_PWM_Init(&htim2) != HAL_OK) { Error_Handler(); } sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET; sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE; if (HAL_TIMEx_MasterConfigSynchronization(&htim2, &sMasterConfig) != HAL_OK) { Error_Handler(); } sConfigOC.OCMode = TIM_OCMODE_PWM1; sConfigOC.Pulse = 500; sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH; sConfigOC.OCFastMode = TIM_OCFAST_DISABLE; if (HAL_TIM_PWM_ConfigChannel(&htim2, &sConfigOC, TIM_CHANNEL_1) != HAL_OK) { Error_Handler(); } /* USER CODE BEGIN TIM2_Init 2 */ /* USER CODE END TIM2_Init 2 */ HAL_TIM_MspPostInit(&htim2); } void HAL_TIM_PWM_MspInit(TIM_HandleTypeDef* tim_pwmHandle) { if(tim_pwmHandle->Instance==TIM2) { /* USER CODE BEGIN TIM2_MspInit 0 */ /* USER CODE END TIM2_MspInit 0 */ /* TIM2 clock enable */ __HAL_RCC_TIM2_CLK_ENABLE(); /* TIM2 interrupt Init */ HAL_NVIC_SetPriority(TIM2_IRQn, 0, 0); HAL_NVIC_EnableIRQ(TIM2_IRQn); /* USER CODE BEGIN TIM2_MspInit 1 */ /* USER CODE END TIM2_MspInit 1 */ } } void HAL_TIM_MspPostInit(TIM_HandleTypeDef* timHandle) { GPIO_InitTypeDef GPIO_InitStruct = {0}; if(timHandle->Instance==TIM2) { /* USER CODE BEGIN TIM2_MspPostInit 0 */ /* USER CODE END TIM2_MspPostInit 0 */ __HAL_RCC_GPIOA_CLK_ENABLE(); /**TIM2 GPIO Configuration PA0-WKUP ------> TIM2_CH1 */ GPIO_InitStruct.Pin = GPIO_PIN_0; GPIO_InitStruct.Mode = GPIO_MODE_AF_PP; GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW; HAL_GPIO_Init(GPIOA, &GPIO_InitStruct); /* USER CODE BEGIN TIM2_MspPostInit 1 */ /* USER CODE END TIM2_MspPostInit 1 */ } } void HAL_TIM_PWM_MspDeInit(TIM_HandleTypeDef* tim_pwmHandle) { if(tim_pwmHandle->Instance==TIM2) { /* USER CODE BEGIN TIM2_MspDeInit 0 */ /* USER CODE END TIM2_MspDeInit 0 */ /* Peripheral clock disable */ __HAL_RCC_TIM2_CLK_DISABLE(); /* TIM2 interrupt Deinit */ HAL_NVIC_DisableIRQ(TIM2_IRQn); /* USER CODE BEGIN TIM2_MspDeInit 1 */ /* USER CODE END TIM2_MspDeInit 1 */ } } /* USER CODE BEGIN 1 */ /* USER CODE END 1 */ ” usart.c：“/* Includes ------------------------------------------------------------------*/ #include "usart.h" /* USER CODE BEGIN 0 */ /* USER CODE END 0 */ UART_HandleTypeDef huart1; /* USART1 init function */ void MX_USART1_UART_Init(void) { /* USER CODE BEGIN USART1_Init 0 */ /* USER CODE END USART1_Init 0 */ /* USER CODE BEGIN USART1_Init 1 */ /* USER CODE END USART1_Init 1 */ 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(); } /* USER CODE BEGIN USART1_Init 2 */ /* USER CODE END USART1_Init 2 */ } void HAL_UART_MspInit(UART_HandleTypeDef* uartHandle) { GPIO_InitTypeDef GPIO_InitStruct = {0}; if(uartHandle->Instance==USART1) { /* USER CODE BEGIN USART1_MspInit 0 */ /* USER CODE END USART1_MspInit 0 */ /* USART1 clock enable */ __HAL_RCC_USART1_CLK_ENABLE(); __HAL_RCC_GPIOB_CLK_ENABLE(); /**USART1 GPIO Configuration PB6 ------> USART1_TX PB7 ------> USART1_RX */ GPIO_InitStruct.Pin = GPIO_PIN_6; GPIO_InitStruct.Mode = GPIO_MODE_AF_PP; GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH; HAL_GPIO_Init(GPIOB, &GPIO_InitStruct); GPIO_InitStruct.Pin = GPIO_PIN_7; GPIO_InitStruct.Mode = GPIO_MODE_INPUT; GPIO_InitStruct.Pull = GPIO_NOPULL; HAL_GPIO_Init(GPIOB, &GPIO_InitStruct); __HAL_AFIO_REMAP_USART1_ENABLE(); /* USART1 interrupt Init */ HAL_NVIC_SetPriority(USART1_IRQn, 0, 0); HAL_NVIC_EnableIRQ(USART1_IRQn); /* USER CODE BEGIN USART1_MspInit 1 */ /* USER CODE END USART1_MspInit 1 */ } } void HAL_UART_MspDeInit(UART_HandleTypeDef* uartHandle) { if(uartHandle->Instance==USART1) { /* USER CODE BEGIN USART1_MspDeInit 0 */ /* USER CODE END USART1_MspDeInit 0 */ /* Peripheral clock disable */ __HAL_RCC_USART1_CLK_DISABLE(); /**USART1 GPIO Configuration PB6 ------> USART1_TX PB7 ------> USART1_RX */ HAL_GPIO_DeInit(GPIOB, GPIO_PIN_6|GPIO_PIN_7); /* USART1 interrupt Deinit */ HAL_NVIC_DisableIRQ(USART1_IRQn); /* USER CODE BEGIN USART1_MspDeInit 1 */ /* USER CODE END USART1_MspDeInit 1 */ } } /* USER CODE BEGIN 1 */ /* USER CODE END 1 */ ” stm32f1xx_it.c：“/* Includes ------------------------------------------------------------------*/ #include "main.h" #include "stm32f1xx_it.h" /* Private includes ----------------------------------------------------------*/ /* USER CODE BEGIN Includes */ /* USER CODE END Includes */ /* Private typedef -----------------------------------------------------------*/ /* USER CODE BEGIN TD */ /* USER CODE END TD */ /* 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 */ /* USER CODE END PV */ /* Private function prototypes -----------------------------------------------*/ /* USER CODE BEGIN PFP */ /* USER CODE END PFP */ /* Private user code ---------------------------------------------------------*/ /* USER CODE BEGIN 0 */ /* USER CODE END 0 */ /* External variables --------------------------------------------------------*/ extern TIM_HandleTypeDef htim2; extern UART_HandleTypeDef huart1; /* USER CODE BEGIN EV */ /* USER CODE END EV */ void NMI_Handler(void) { /* USER CODE BEGIN NonMaskableInt_IRQn 0 */ /* USER CODE END NonMaskableInt_IRQn 0 */ /* USER CODE BEGIN NonMaskableInt_IRQn 1 */ while (1) { } /* USER CODE END NonMaskableInt_IRQn 1 */ } void HardFault_Handler(void) { /* USER CODE BEGIN HardFault_IRQn 0 */ /* USER CODE END HardFault_IRQn 0 */ while (1) { /* USER CODE BEGIN W1_HardFault_IRQn 0 */ /* USER CODE END W1_HardFault_IRQn 0 */ } } void MemManage_Handler(void) { /* USER CODE BEGIN MemoryManagement_IRQn 0 */ /* USER CODE END MemoryManagement_IRQn 0 */ while (1) { /* USER CODE BEGIN W1_MemoryManagement_IRQn 0 */ /* USER CODE END W1_MemoryManagement_IRQn 0 */ } } void BusFault_Handler(void) { /* USER CODE BEGIN BusFault_IRQn 0 */ /* USER CODE END BusFault_IRQn 0 */ while (1) { /* USER CODE BEGIN W1_BusFault_IRQn 0 */ /* USER CODE END W1_BusFault_IRQn 0 */ } } void UsageFault_Handler(void) { /* USER CODE BEGIN UsageFault_IRQn 0 */ /* USER CODE END UsageFault_IRQn 0 */ while (1) { /* USER CODE BEGIN W1_UsageFault_IRQn 0 */ /* USER CODE END W1_UsageFault_IRQn 0 */ } } void SVC_Handler(void) { /* USER CODE BEGIN SVCall_IRQn 0 */ /* USER CODE END SVCall_IRQn 0 */ /* USER CODE BEGIN SVCall_IRQn 1 */ /* USER CODE END SVCall_IRQn 1 */ } void DebugMon_Handler(void) { /* USER CODE BEGIN DebugMonitor_IRQn 0 */ /* USER CODE END DebugMonitor_IRQn 0 */ /* USER CODE BEGIN DebugMonitor_IRQn 1 */ /* USER CODE END DebugMonitor_IRQn 1 */ } void PendSV_Handler(void) { /* USER CODE BEGIN PendSV_IRQn 0 */ /* USER CODE END PendSV_IRQn 0 */ /* USER CODE BEGIN PendSV_IRQn 1 */ /* USER CODE END PendSV_IRQn 1 */ } void SysTick_Handler(void) { /* USER CODE BEGIN SysTick_IRQn 0 */ /* USER CODE END SysTick_IRQn 0 */ HAL_IncTick(); /* USER CODE BEGIN SysTick_IRQn 1 */ /* USER CODE END SysTick_IRQn 1 */ } void RCC_IRQHandler(void) { /* USER CODE BEGIN RCC_IRQn 0 */ /* USER CODE END RCC_IRQn 0 */ /* USER CODE BEGIN RCC_IRQn 1 */ /* USER CODE END RCC_IRQn 1 */ } void TIM2_IRQHandler(void) { /* USER CODE BEGIN TIM2_IRQn 0 */ /* USER CODE END TIM2_IRQn 0 */ HAL_TIM_IRQHandler(&htim2); /* USER CODE BEGIN TIM2_IRQn 1 */ /* USER CODE END TIM2_IRQn 1 */ } void USART1_IRQHandler(void) { /* USER CODE BEGIN USART1_IRQn 0 */ /* USER CODE END USART1_IRQn 0 */ HAL_UART_IRQHandler(&huart1); /* USER CODE BEGIN USART1_IRQn 1 */ /* USER CODE END USART1_IRQn 1 */ } /* USER CODE BEGIN 1 */ /* USER CODE END 1 */” main.h：“/* Define to prevent recursive inclusion -------------------------------------*/ #ifndef __MAIN_H #define __MAIN_H #ifdef __cplusplus extern "C" { #endif /* Includes ------------------------------------------------------------------*/ #include "stm32f1xx_hal.h" /* Private includes ----------------------------------------------------------*/ /* USER CODE BEGIN Includes */ /* USER CODE END Includes */ /* Exported types ------------------------------------------------------------*/ /* USER CODE BEGIN ET */ /* USER CODE END ET */ /* Exported constants --------------------------------------------------------*/ /* USER CODE BEGIN EC */ /* USER CODE END EC */ /* Exported macro ------------------------------------------------------------*/ /* USER CODE BEGIN EM */ /* USER CODE END EM */ /* Exported functions prototypes ---------------------------------------------*/ void Error_Handler(void); /* USER CODE BEGIN EFP */ /* USER CODE END EFP */ /* Private defines -----------------------------------------------------------*/ #define DIR_Pin GPIO_PIN_0 #define DIR_GPIO_Port GPIOC #define EN_Pin GPIO_PIN_1 #define EN_GPIO_Port GPIOC /* USER CODE BEGIN Private defines */ /* USER CODE END Private defines */ #ifdef __cplusplus } #endif #endif /* __MAIN_H */ ” gpio.h：“/* Define to prevent recursive inclusion -------------------------------------*/ #ifndef __GPIO_H__ #define __GPIO_H__ #ifdef __cplusplus extern "C" { #endif /* Includes ------------------------------------------------------------------*/ #include "main.h" /* USER CODE BEGIN Includes */ /* USER CODE END Includes */ /* USER CODE BEGIN Private defines */ /* USER CODE END Private defines */ void MX_GPIO_Init(void); /* USER CODE BEGIN Prototypes */ /* USER CODE END Prototypes */ #ifdef __cplusplus } #endif #endif /*__ GPIO_H__ */” tim.h：“/* Define to prevent recursive inclusion -------------------------------------*/ #ifndef __TIM_H__ #define __TIM_H__ #ifdef __cplusplus extern "C" { #endif /* Includes ------------------------------------------------------------------*/ #include "main.h" /* USER CODE BEGIN Includes */ /* USER CODE END Includes */ extern TIM_HandleTypeDef htim2; /* USER CODE BEGIN Private defines */ /* USER CODE END Private defines */ void MX_TIM2_Init(void); void HAL_TIM_MspPostInit(TIM_HandleTypeDef *htim); /* USER CODE BEGIN Prototypes */ /* USER CODE END Prototypes */ #ifdef __cplusplus } #endif #endif /* __TIM_H__ */ ” usart.h：“/* Define to prevent recursive inclusion -------------------------------------*/ #ifndef __USART_H__ #define __USART_H__ #ifdef __cplusplus extern "C" { #endif /* Includes ------------------------------------------------------------------*/ #include "main.h" /* USER CODE BEGIN Includes */ /* USER CODE END Includes */ extern UART_HandleTypeDef huart1; /* USER CODE BEGIN Private defines */ /* USER CODE END Private defines */ void MX_USART1_UART_Init(void); /* USER CODE BEGIN Prototypes */ /* USER CODE END Prototypes */ #ifdef __cplusplus } #endif #endif /* __USART_H__ */” stm32f1xx_it.h：“/* Define to prevent recursive inclusion -------------------------------------*/ #ifndef __STM32F1xx_IT_H #define __STM32F1xx_IT_H #ifdef __cplusplus extern "C" { #endif /* Private includes ----------------------------------------------------------*/ /* USER CODE BEGIN Includes */ /* USER CODE END Includes */ /* Exported types ------------------------------------------------------------*/ /* USER CODE BEGIN ET */ /* USER CODE END ET */ /* Exported constants --------------------------------------------------------*/ /* USER CODE BEGIN EC */ /* USER CODE END EC */ /* Exported macro ------------------------------------------------------------*/ /* USER CODE BEGIN EM */ /* USER CODE END EM */ /* Exported functions prototypes ---------------------------------------------*/ void NMI_Handler(void); 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