STM32F446移植USB驱动，实现外部FLASH模拟U盘嵌入式笔尖清风的博客-

USB（Universal Serial Bus通用串行总线）是一个外部总线标准，用于规范电脑与外部设备的连接和通讯，是应用在PC领域的接口技术，支持设备的即插即用和热插拔功能。STM32芯片自带有USB功能，带来了更多的可玩性，但也更加复杂，之前在STM32F103上实现了USB库的移植，由于F103的USB功能简单，移植比较顺利，具体的方法见本人的博客：STM32F1移植USB库实现外部FLASH模拟U盘功能。
相较于 STMF1，STM32F4 的功能大为增强，引入了 OTG 功能，最近入手了一块 NUCLEO-64 开发板，板载芯片是 STM32F446RET6，尝试在上面移植 USB 的 MSC 驱动。
在参考了野火和原子的例程后，没能成功移植官网的USB库，其中一个原因在于例程所使用的芯片是 STM32F429，这一芯片的时钟树结构与 STM32F446 存在差异。从 CubeMX 上可以看出，STM32F429 的 USB 时钟只能来自PLL，如图1，无法在运行于推荐的180MHz主频的情况下获得48MHz的USB 时钟，只能采取降频至144MHz，或超频至192MHz（野火和原子的例程采用的方法）。

图1. STM32F429IGTx时钟树
相比于此，STM32F446RE 的 USB 时钟来源可以选择 PLLSAIP，由 PLLSAI 倍频产生，这就同时满足了180MHz的运行频率和 USB 的48MHz时钟的要求。

图2. STM32F446RETx时钟树
由于与 PLLSAI 相关的资料和程序很少，而且 USB 库的移植相对来说确实麻烦，所以采用 CubeMX 来配置HAL库，实现外部FLASH 模拟U盘的功能。

移植过程
1、在 CubeMX 中选择相对应的芯片，配置 RCC，如下图：

2、在 Connectivity 中选择 USB_OTG_FS（全速模式），配置为 Device_Only 模式，如下图：

3、在 Middleware 中选择 USB_DEVICE，在 Class For FS IP 中选择 Mass Storage Class，由于采用的存储介质是 FLASH，所以MSC_MEDIA_PACKET 配置为 4096 bytes，如果是SD卡采用默认的 512 bytes 配置，如下图：

4、配置 USB 的 中断优先级为5，如下图：

5、配置时钟树，如下图：

6、配置堆空间 Minimum Heap Size 为 0x1200，作为 USB 的缓冲，如下图：

7、由于之前已经写好了外部 FLASH 移植 FATFS 的程序，不想重复折腾，这里将与 USB 驱动相关的文件拷贝出来，直接添加到之前的工程中。CubeMX 生成的与USB相关的文件位于：
“…MiddlewaresSTSTM32_USB_Device_Library”

…Src中的文件

…Inc中的文件

将上述文件拷贝至之前的移植FATFS文件系统的工程文件下，如下图

并将stm32f4xx_hal_msp.c文件也拷贝到User文件夹，打开工程添加USB库文件代码如下：

8、编译后存在两个错误：

这两个错误都是由于将函数定义为了静态函数，在 main.c 文件中将对应函数的 static 关键字去掉，并在 main.h 中声明 Error_Handler() 函数。
在 main.c 中的时钟初始化函数添加PLLSAI的设置，可以复制CubeMX生成工程中的 main.c 文件中的时钟初始化函数

void SystemClock_Config(void) {    RCC_ClkInitTypeDef RCC_ClkInitStruct;    RCC_OscInitTypeDef RCC_OscInitStruct;  RCC_PeriphCLKInitTypeDef PeriphClkInitStruct; /** Configure the main internal regulator output voltage     */ __HAL_RCC_PWR_CLK_ENABLE(); __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1); /* 使能HSE，配置HSE为PLL的时钟源，配置PLL的各种分频因子M N P Q    * PLLCLK = HSE/M*N/P = 12M / 25 *360 / 2 = 180M   */  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 = 360;    RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;   RCC_OscInitStruct.PLL.PLLQ = 7;   RCC_OscInitStruct.PLL.PLLR = 2; if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) { Error_Handler(); } /** Activate the Over-Drive mode     */ if (HAL_PWREx_EnableOverDrive() != HAL_OK) { Error_Handler(); } /** Initializes the CPU, AHB and APB busses clocks     */ /* 选择PLLCLK作为SYSCLK，并配置 HCLK, PCLK1 and PCLK2 的时钟分频因子    * SYSCLK = PLLCLK     = 180M   * HCLK   = SYSCLK / 1 = 180M   * PCLK2  = SYSCLK / 2 = 90M   * PCLK1  = SYSCLK / 4 = 45M   */    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_DIV4;    RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2; if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK) { Error_Handler(); }    PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_CLK48;    PeriphClkInitStruct.PLLSAI.PLLSAIM = 4;    PeriphClkInitStruct.PLLSAI.PLLSAIN = 96;    PeriphClkInitStruct.PLLSAI.PLLSAIQ = 2;    PeriphClkInitStruct.PLLSAI.PLLSAIP = RCC_PLLSAIP_DIV4;    PeriphClkInitStruct.PLLSAIDivQ = 1;    PeriphClkInitStruct.Clk48ClockSelection = RCC_CLK48CLKSOURCE_PLLSAIP; if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK) { Error_Handler(); } } 

9、在 usbd_storage_if.c 中添加底层读写 FLASH 的代码：

/* USER CODE BEGIN Header */ /**   ******************************************************************************   * @file           : usbd_storage_if.c   * @version        : v1.0_Cube   * @brief          : Memory management layer.   ******************************************************************************   * @attention   *   * <h2><center>&copy; Copyright (c) 2020 STMicroelectronics.   * All rights reserved.</center></h2>   *   * This software component is licensed by ST under Ultimate Liberty license   * SLA0044, the "License"; You may not use this file except in compliance with   * the License. You may obtain a copy of the License at:   *                             www.st.com/SLA0044   *   ******************************************************************************   */ /* USER CODE END Header */ /* Includes ------------------------------------------------------------------*/ #include "usbd_storage_if.h" /* USER CODE BEGIN INCLUDE */ #include "./flash/bsp_spi_flash.h" /* USER CODE END INCLUDE */ /* Private typedef -----------------------------------------------------------*/ /* Private define ------------------------------------------------------------*/ /* Private macro -------------------------------------------------------------*/ /* USER CODE BEGIN PV */ /* Private variables ---------------------------------------------------------*/ /* USER CODE END PV */ /** @addtogroup STM32_USB_OTG_DEVICE_LIBRARY   * @brief Usb device.   * @{   */ /** @defgroup USBD_STORAGE   * @brief Usb mass storage device module   * @{   */ /** @defgroup USBD_STORAGE_Private_TypesDefinitions   * @brief Private types.   * @{   */ /* USER CODE BEGIN PRIVATE_TYPES */ /* USER CODE END PRIVATE_TYPES */ /**   * @}   */ /** @defgroup USBD_STORAGE_Private_Defines   * @brief Private defines.   * @{   */ #define STORAGE_LUN_NBR                  1 #define STORAGE_BLK_NBR                  4096//0x10000 #define STORAGE_BLK_SIZ                  4096//0x200 /* USER CODE BEGIN PRIVATE_DEFINES */ /* USER CODE END PRIVATE_DEFINES */ /**   * @}   */ /** @defgroup USBD_STORAGE_Private_Macros   * @brief Private macros.   * @{   */ /* USER CODE BEGIN PRIVATE_MACRO */ /* USER CODE END PRIVATE_MACRO */ /**   * @}   */ /** @defgroup USBD_STORAGE_Private_Variables   * @brief Private variables.   * @{   */ /* USER CODE BEGIN INQUIRY_DATA_FS */ /** USB Mass storage Standard Inquiry Data. */ const int8_t STORAGE_Inquirydata_FS[] = {/* 36 */ /* LUN 0 */ 0x00, 0x80, 0x02, 0x02, (STANDARD_INQUIRY_DATA_LEN - 5), 0x00, 0x00, 0x00, 'S', 'T', 'M', ' ', ' ', ' ', ' ', ' ', /* Manufacturer : 8 bytes */ 'P', 'r', 'o', 'd', 'u', 'c', 't', ' ', /* Product      : 16 Bytes */ ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', '0', '.', '0' ,'1' /* Version      : 4 Bytes */ }; /* USER CODE END INQUIRY_DATA_FS */ /* USER CODE BEGIN PRIVATE_VARIABLES */ /* USER CODE END PRIVATE_VARIABLES */ /**   * @}   */ /** @defgroup USBD_STORAGE_Exported_Variables   * @brief Public variables.   * @{   */ extern USBD_HandleTypeDef hUsbDeviceFS; /* USER CODE BEGIN EXPORTED_VARIABLES */ /* USER CODE END EXPORTED_VARIABLES */ /**   * @}   */ /** @defgroup USBD_STORAGE_Private_FunctionPrototypes   * @brief Private functions declaration.   * @{   */ static int8_t STORAGE_Init_FS(uint8_t lun); static int8_t STORAGE_GetCapacity_FS(uint8_t lun, uint32_t *block_num, uint16_t *block_size); static int8_t STORAGE_IsReady_FS(uint8_t lun); static int8_t STORAGE_IsWriteProtected_FS(uint8_t lun); static int8_t STORAGE_Read_FS(uint8_t lun, uint8_t *buf, uint32_t blk_addr, uint16_t blk_len); static int8_t STORAGE_Write_FS(uint8_t lun, uint8_t *buf, uint32_t blk_addr, uint16_t blk_len); static int8_t STORAGE_GetMaxLun_FS(void); /* USER CODE BEGIN PRIVATE_FUNCTIONS_DECLARATION */ /* USER CODE END PRIVATE_FUNCTIONS_DECLARATION */ /**   * @}   */  USBD_StorageTypeDef USBD_Storage_Interface_fops_FS = {   STORAGE_Init_FS,   STORAGE_GetCapacity_FS,   STORAGE_IsReady_FS,   STORAGE_IsWriteProtected_FS,   STORAGE_Read_FS,   STORAGE_Write_FS,   STORAGE_GetMaxLun_FS, (int8_t *)STORAGE_Inquirydata_FS }; /* Private functions ---------------------------------------------------------*/ /**   * @brief  Initializes over USB FS IP   * @param  lun:   * @retval USBD_OK if all operations are OK else USBD_FAIL   */ int8_t STORAGE_Init_FS(uint8_t lun) { /* USER CODE BEGIN 2 */ SPI_FLASH_Init(); if (SPI_FLASH_ReadID() != sFLASH_ID) { //printf("errorrn"); return (USBD_FAIL); } return (USBD_OK); /* USER CODE END 2 */ } /**   * @brief  .   * @param  lun: .   * @param  block_num: .   * @param  block_size: .   * @retval USBD_OK if all operations are OK else USBD_FAIL   */ int8_t STORAGE_GetCapacity_FS(uint8_t lun, uint32_t *block_num, uint16_t *block_size) { /* USER CODE BEGIN 3 */ *block_num  = STORAGE_BLK_NBR; *block_size = STORAGE_BLK_SIZ; return (USBD_OK); /* USER CODE END 3 */ } /**   * @brief  .   * @param  lun: .   * @retval USBD_OK if all operations are OK else USBD_FAIL   */ int8_t STORAGE_IsReady_FS(uint8_t lun) { /* USER CODE BEGIN 4 */ if (SPI_FLASH_ReadID() == sFLASH_ID) { //printf("errorrn"); return (USBD_OK); } else { return (USBD_FAIL); } //return (USBD_OK); /* USER CODE END 4 */ } /**   * @brief  .   * @param  lun: .   * @retval USBD_OK if all operations are OK else USBD_FAIL   */ int8_t STORAGE_IsWriteProtected_FS(uint8_t lun) { /* USER CODE BEGIN 5 */ return (USBD_OK); /* USER CODE END 5 */ } /**   * @brief  .   * @param  lun: .   * @retval USBD_OK if all operations are OK else USBD_FAIL   */ int8_t STORAGE_Read_FS(uint8_t lun, uint8_t *buf, uint32_t blk_addr, uint16_t blk_len) { /* USER CODE BEGIN 6 */ SPI_FLASH_BufferRead(buf, blk_addr*STORAGE_BLK_SIZ, blk_len*STORAGE_BLK_SIZ); return (USBD_OK); /* USER CODE END 6 */ } /**   * @brief  .   * @param  lun: .   * @retval USBD_OK if all operations are OK else USBD_FAIL   */ int8_t STORAGE_Write_FS(uint8_t lun, uint8_t *buf, uint32_t blk_addr, uint16_t blk_len) { /* USER CODE BEGIN 7 */ SPI_FLASH_SectorErase(blk_addr*STORAGE_BLK_SIZ); SPI_FLASH_BufferWrite(buf, blk_addr*STORAGE_BLK_SIZ, blk_len*STORAGE_BLK_SIZ); return (USBD_OK); /* USER CODE END 7 */ } /**   * @brief  .   * @param  None   * @retval .   */ int8_t STORAGE_GetMaxLun_FS(void) { /* USER CODE BEGIN 8 */ return (STORAGE_LUN_NBR - 1); /* USER CODE END 8 */ } /* USER CODE BEGIN PRIVATE_FUNCTIONS_IMPLEMENTATION */ /* USER CODE END PRIVATE_FUNCTIONS_IMPLEMENTATION */ /**   * @}   */ /**   * @}   */ /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/ 

10、修改启动文件中的堆空间大小

11、在 stm32f4xx_it.c 添加 USB 中断服务函数

/**   ******************************************************************************   * @file    Templates/Src/stm32f4xx_it.c    * @author  MCD Application Team   * @brief   Main Interrupt Service Routines.   *          This file provides template for all exceptions handler and    *          peripherals interrupt service routine.   ******************************************************************************   * @attention   *   * <h2><center>&copy; COPYRIGHT(c) 2017 STMicroelectronics</center></h2>   *   * Redistribution and use in source and binary forms, with or without modification,   * are permitted provided that the following conditions are met:   *   1. Redistributions of source code must retain the above copyright notice,   *      this list of conditions and the following disclaimer.   *   2. Redistributions in binary form must reproduce the above copyright notice,   *      this list of conditions and the following disclaimer in the documentation   *      and/or other materials provided with the distribution.   *   3. Neither the name of STMicroelectronics nor the names of its contributors   *      may be used to endorse or promote products derived from this software   *      without specific prior written permission.   *   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE   * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.   *   ******************************************************************************   */ /* Includes ------------------------------------------------------------------*/ #include "main.h" #include "stm32f4xx_it.h" extern PCD_HandleTypeDef hpcd_USB_OTG_FS; /** @addtogroup STM32F4xx_HAL_Examples   * @{   */ /** @addtogroup Templates   * @{   */ /* Private typedef -----------------------------------------------------------*/ /* Private define ------------------------------------------------------------*/ /* Private macro -------------------------------------------------------------*/ /* Private variables ---------------------------------------------------------*/ /* Private function prototypes -----------------------------------------------*/ /* Private functions ---------------------------------------------------------*/ /******************************************************************************/ /*            Cortex-M4 Processor Exceptions Handlers                         */ /******************************************************************************/ /**   * @brief  This function handles NMI exception.   * @param  None   * @retval None   */ void NMI_Handler(void) { } /**   * @brief  This function handles Hard Fault exception.   * @param  None   * @retval None   */ void HardFault_Handler(void) { /* Go to infinite loop when Hard Fault exception occurs */ while (1) { } } /**   * @brief  This function handles Memory Manage exception.   * @param  None   * @retval None   */ void MemManage_Handler(void) { /* Go to infinite loop when Memory Manage exception occurs */ while (1) { } } /**   * @brief  This function handles Bus Fault exception.   * @param  None   * @retval None   */ void BusFault_Handler(void) { /* Go to infinite loop when Bus Fault exception occurs */ while (1) { } } /**   * @brief  This function handles Usage Fault exception.   * @param  None   * @retval None   */ void UsageFault_Handler(void) { /* Go to infinite loop when Usage Fault exception occurs */ while (1) { } } /**   * @brief  This function handles SVCall exception.   * @param  None   * @retval None   */ void SVC_Handler(void) { } /**   * @brief  This function handles Debug Monitor exception.   * @param  None   * @retval None   */ void DebugMon_Handler(void) { } /**   * @brief  This function handles PendSVC exception.   * @param  None   * @retval None   */ void PendSV_Handler(void) { } /**   * @brief  This function handles SysTick Handler.   * @param  None   * @retval None   */ void SysTick_Handler(void) { HAL_IncTick(); } /******************************************************************************/ /*                 STM32F4xx Peripherals Interrupt Handlers                   */ /*  Add here the Interrupt Handler for the used peripheral(s) (PPP), for the  */ /*  available peripheral interrupt handler's name please refer to the startup */ /*  file (startup_stm32f4xx.s).                                               */ /******************************************************************************/ /**   * @brief  This function handles PPP interrupt request.   * @param  None   * @retval None   */ /*void PPP_IRQHandler(void) { }*/ /**   * @}   */ /**   * @}   */ /**   * @brief This function handles USB On The Go FS global interrupt.   */ void OTG_FS_IRQHandler(void) { /* USER CODE BEGIN OTG_FS_IRQn 0 */ //printf("111rn"); /* USER CODE END OTG_FS_IRQn 0 */ HAL_PCD_IRQHandler(&hpcd_USB_OTG_FS); /* USER CODE BEGIN OTG_FS_IRQn 1 */ /* USER CODE END OTG_FS_IRQn 1 */ } /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/ 

12、在 main.c 中添加 USB 库相关头文件，并初始化 USB 外设

/**   ******************************************************************************   * @file    main.c   * @author  Asher   * @version V1.0   * @date    2020-05-16   * @brief   外部FLASH模拟U盘   ******************************************************************************   * @attention   *   * 实验平台:  STM32F446RET6    *    *    *   ******************************************************************************   */ /* Includes ------------------------------------------------------------------*/ #include "main.h" #include "./usart/bsp_usart.h" #include "./flash/bsp_spi_flash.h" #include "ff.h" #include "usb_device.h" #include "usbd_core.h" //函数声明 void SystemClock_Config(void); void Error_Handler(void); static void MX_GPIO_Init(void); //全局变量 FATFS fs; /* FatFs文件系统对象 */ FIL fnew; /* 文件对象 */ FRESULT res_flash; /* 文件操作结果 */ UINT fnum; /* 文件成功读写数量 */ BYTE ReadBuffer[1024]={0}; /* 读缓冲区 */ BYTE WriteBuffer[] = "FatFs文件系统测试数据。rn"; /* 写缓冲区*/ BYTE work[FF_MAX_SS]; /**   * @brief  Main program   * @param  None   * @retval None   */ int main(void) { HAL_Init(); SystemClock_Config(); //初始化USB MX_GPIO_Init(); MX_USB_DEVICE_Init(); //初始化串口 USART_Config(); printf("****** FatFs文件系统实验 ******rn"); //在外部SPI Flash挂载文件系统，文件系统挂载时会对SPI设备初始化 //初始化函数调用流程如下 //f_mount()->find_volume()->disk_initialize->SPI_FLASH_Init()  res_flash = f_mount(&fs,"0:",1); /*----------------------- 格式化测试 -----------------*/ /* 如果没有文件系统就格式化创建创建文件系统 */ if(res_flash == FR_NO_FILESYSTEM) { printf("》FLASH还没有文件系统，即将进行格式化...rn"); /* 格式化 */   res_flash = f_mkfs("0:",0,work,sizeof work); if(res_flash == FR_OK) { printf("》FLASH已成功格式化文件系统。rn"); /* 格式化后，先取消挂载 */    res_flash = f_mount(NULL,"0:",1); /* 重新挂载*/       res_flash = f_mount(&fs,"0:",1); } else { printf("《《格式化失败。(%d)》》rn",res_flash); while(1); } } else if(res_flash!=FR_OK) { printf("！！外部Flash挂载文件系统失败。(%d)rn",res_flash); printf("！！可能原因：SPI Flash初始化不成功。rn"); while(1); } else { printf("》文件系统挂载成功，可以进行读写测试rn"); } /*----------------------- 文件系统测试：写测试 -------------------*/ /* 打开文件，每次都以新建的形式打开，属性为可写 */ printf("rn****** 即将进行文件写入测试... ******rn");   res_flash = f_open(&fnew, "0:FatFs读写测试文件.txt",FA_CREATE_ALWAYS | FA_WRITE ); if ( res_flash == FR_OK ) { printf("》打开/创建FatFs读写测试文件.txt文件成功，向文件写入数据。rn"); /* 将指定存储区内容写入到文件内 */   res_flash=f_write(&fnew,WriteBuffer,sizeof(WriteBuffer),&fnum); if(res_flash==FR_OK) { printf("》文件写入成功，写入字节数据：%dn",fnum); printf("》向文件写入的数据为：rn%srn",WriteBuffer); } else { printf("！！文件写入失败：(%d)n",res_flash); } /* 不再读写，关闭文件 */ f_close(&fnew); } else { printf("！！打开/创建文件失败。(%d)rn",res_flash); } /*------------------- 文件系统测试：读测试 --------------------------*/ printf("****** 即将进行文件读取测试... ******rn");  res_flash = f_open(&fnew, "0:FatFs读写测试文件.txt",FA_OPEN_EXISTING | FA_READ); if(res_flash == FR_OK) { printf("》打开文件成功。rn");   res_flash = f_read(&fnew, ReadBuffer, sizeof(ReadBuffer), &fnum); if(res_flash==FR_OK) { printf("》文件读取成功,读到字节数据：%drn",fnum); printf("》读取得的文件数据为：rn%s rn", ReadBuffer); } else { printf("！！文件读取失败：(%d)n",res_flash); } } else { printf("！！打开文件失败。rn"); } /* 不再读写，关闭文件 */ f_close(&fnew); /* 不再使用文件系统，取消挂载文件系统 */ //f_mount(NULL,"0:",1); /* Infinite loop */ while (1) { } } /**   * @brief  System Clock Configuration   *         The system Clock is configured as follow :    *            System Clock source            = PLL (HSI)   *            SYSCLK(Hz)                     = 180000000   *            HCLK(Hz)                       = 180000000   *            AHB Prescaler                  = 1   *            APB1 Prescaler                 = 4   *            APB2 Prescaler                 = 2   *            HSE Frequency(Hz)              = 8000000   *            PLL_M                          = 8   *            PLL_N                          = 360   *            PLL_P                          = 2   *            PLL_Q                          = 7   *            PLL_R                          = 2   *            VDD(V)                         = 3.3   *            Main regulator output voltage  = Scale1 mode   *            Flash Latency(WS)              = 5   * @param  None   * @retval None   */ void SystemClock_Config(void) {   RCC_ClkInitTypeDef RCC_ClkInitStruct;   RCC_OscInitTypeDef RCC_OscInitStruct;  RCC_PeriphCLKInitTypeDef PeriphClkInitStruct; /** Configure the main internal regulator output voltage    */ __HAL_RCC_PWR_CLK_ENABLE(); __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1); /* 使能HSE，配置HSE为PLL的时钟源，配置PLL的各种分频因子M N P Q    * PLLCLK = HSE/M*N/P = 12M / 25 *360 / 2 = 180M   */   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 = 360;   RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;   RCC_OscInitStruct.PLL.PLLQ = 7;   RCC_OscInitStruct.PLL.PLLR = 2; if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) { Error_Handler(); } /** Activate the Over-Drive mode    */ if (HAL_PWREx_EnableOverDrive() != HAL_OK) { Error_Handler(); } /** Initializes the CPU, AHB and APB busses clocks    */ /* 选择PLLCLK作为SYSCLK，并配置 HCLK, PCLK1 and PCLK2 的时钟分频因子    * SYSCLK = PLLCLK     = 180M   * HCLK   = SYSCLK / 1 = 180M   * PCLK2  = SYSCLK / 2 = 90M   * PCLK1  = SYSCLK / 4 = 45M   */   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_DIV4;   RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2; if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK) { Error_Handler(); }    PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_CLK48;   PeriphClkInitStruct.PLLSAI.PLLSAIM = 4;   PeriphClkInitStruct.PLLSAI.PLLSAIN = 96;   PeriphClkInitStruct.PLLSAI.PLLSAIQ = 2;   PeriphClkInitStruct.PLLSAI.PLLSAIP = RCC_PLLSAIP_DIV4;   PeriphClkInitStruct.PLLSAIDivQ = 1;   PeriphClkInitStruct.Clk48ClockSelection = RCC_CLK48CLKSOURCE_PLLSAIP; if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK) { Error_Handler(); } } /**   * @brief GPIO Initialization Function   * @param None   * @retval None   */ static void MX_GPIO_Init(void) { /* GPIO Ports Clock Enable */ __HAL_RCC_GPIOH_CLK_ENABLE(); __HAL_RCC_GPIOA_CLK_ENABLE(); } /**   * @brief  This function is executed in case of error occurrence.   * @param  None   * @retval None   */ void Error_Handler(void) { /* User may add here some code to deal with this error */ while(1) { } } #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 can add his own implementation to report the file name and line number,      ex: printf("Wrong parameters value: file %s on line %drn", file, line) */ /* Infinite loop */ while (1) { } } #endif /**   * @}   */ /**   * @}   */ /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/ 

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