其實本身是很容易實現的，但中途遇到了一個以往較少注意到的問題：堆棧空間。
參考這個：https://www.cnblogs.com/qsyll0916/p/8013136.html
總的來說，就是因爲堆空間分配不足，導致沒有足夠的空間給USB作緩衝。這個問題網上很多人遇到過，但是
解決這問題帖子沒找到。原子的HAL例程是將FLASH當成512字節扇區進行讀寫的，原因是爲了同時掛載SD卡（512）
而堆空間STM32默認就是0x200，512字節。所以原子哥沒有遇到這問題。至於硬石的代碼，我發現他的程序
誤以爲USB緩衝使用的是棧空間，當然，實際上使用的是堆空間。所以他修改了啓動文件的堆棧大小爲：
Stack_Size EQU 0x1200
Heap_Size EQU 0x200正確應爲：
Stack_Size EQU 0x200
Heap_Size EQU 0x1200因此，硬石的教程裏面沒有USB串行FLASH模擬U盤的章節，我猜測他是沒調通這個功能，哈哈。
言歸正傳，STM32CubeMX配置圖：
我的FLASH是複用SPI1，PB3、4、5引腳。CS引腳爲PB0
USB：選擇Device Only ， Mass Storage Class這兩個選項
RCC與SYS：SWD下載程序，以及選擇外部晶振
PA6、PA7：這個是我板子上的兩個LED的接口，不用理會。
SPI1複用PB3、4、5：先點PB3，然後在彈出的選項中選擇SPI1_SCK，PB4、5方法相同
然後再在左邊選項卡開啓SPI1，這樣SPI1就複用到PB3、4、5了。
時鐘樹配置：這個不貼圖了，配製成正確的時鐘就好。
Configuration:
首先修改SPI1的CS引腳，因爲默認SPI1是軟件控制的，我使用了PB0控制它：
USB Configuration
這裏修改了USB讀/寫緩衝區的大小，設爲4096。因爲我的串行FLASH的扇區爲4096字節。
當然，如果是SD卡，使用默認的512就可以了。
Project -> Setting
我使用的是MDK，文件名進行了修改，然後修改了堆的大小。
Code Generator：
把這個勾選上，不同外設建立不同.c .h文件。
至此，修改完成，可以生成代碼了。
生成代碼後，將DeBug裏面，Flash Download的Reset And Run勾上，因爲生成的工程默認不勾。
還有在Target裏面：Use MicroLIB
使用微軟的庫，這個默認是勾上的。你不用它的庫也可以手動取消掉。
生成的代碼文件裏面，主要修改："usbd_storage_if.c"
/**
******************************************************************************
* @file : usbd_storage_if.c
* @version : v1.0_Cube
* @brief : Memory management layer.
******************************************************************************
* This notice applies to any and all portions of this file
* that are not between comment pairs USER CODE BEGIN and
* USER CODE END. Other portions of this file, whether
* inserted by the user or by software development tools
* are owned by their respective copyright owners.
*
* Copyright (c) 2018 STMicroelectronics International N.V.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted, provided that the following conditions are met:
*
* 1. Redistribution 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 other
* contributors to this software may be used to endorse or promote products
* derived from this software without specific written permission.
* 4. This software, including modifications and/or derivative works of this
* software, must execute solely and exclusively on microcontroller or
* microprocessor devices manufactured by or for STMicroelectronics.
* 5. Redistribution and use of this software other than as permitted under
* this license is void and will automatically terminate your rights under
* this license.
*
* THIS SOFTWARE IS PROVIDED BY STMICROELECTRONICS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS, IMPLIED OR STATUTORY WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NON-INFRINGEMENT OF THIRD PARTY INTELLECTUAL PROPERTY
* RIGHTS ARE DISCLAIMED TO THE FULLEST EXTENT PERMITTED BY LAW. IN NO EVENT
* SHALL STMICROELECTRONICS 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 "usbd_storage_if.h"
#include "spi.h"
/* USER CODE BEGIN INCLUDE */
/* 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 512
#define STORAGE_BLK_SIZ 4096
/* 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 */
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)
{
if(SPI_FLASH_ReadID() == FLASH_ID)
return (USBD_OK);
else
return -1;
}
/**
* @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)
{
SPI_FLASH_BufferRead(buf, blk_addr*STORAGE_BLK_SIZ, blk_len*STORAGE_BLK_SIZ);
return (USBD_OK);
}
/**
* @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)
{
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);
}
/**
* @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****/
底層的SPI FLASH的函數，需要自己構建，我的代碼如下：
/**
******************************************************************************
* File Name : SPI.c
* Description : This file provides code for the configuration
* of the SPI instances.
******************************************************************************
* This notice applies to any and all portions of this file
* that are not between comment pairs USER CODE BEGIN and
* USER CODE END. Other portions of this file, whether
* inserted by the user or by software development tools
* are owned by their respective copyright owners.
*
* Copyright (c) 2018 STMicroelectronics International N.V.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted, provided that the following conditions are met:
*
* 1. Redistribution 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 other
* contributors to this software may be used to endorse or promote products
* derived from this software without specific written permission.
* 4. This software, including modifications and/or derivative works of this
* software, must execute solely and exclusively on microcontroller or
* microprocessor devices manufactured by or for STMicroelectronics.
* 5. Redistribution and use of this software other than as permitted under
* this license is void and will automatically terminate your rights under
* this license.
*
* THIS SOFTWARE IS PROVIDED BY STMICROELECTRONICS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS, IMPLIED OR STATUTORY WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NON-INFRINGEMENT OF THIRD PARTY INTELLECTUAL PROPERTY
* RIGHTS ARE DISCLAIMED TO THE FULLEST EXTENT PERMITTED BY LAW. IN NO EVENT
* SHALL STMICROELECTRONICS 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 "spi.h"
#include "gpio.h"
#define SPI_FLASH_PageSize 256
/* USER CODE BEGIN 0 */
/* USER CODE END 0 */
SPI_HandleTypeDef hspi1;
uint8_t d_read,d_send;
/* SPI1 init function */
void MX_SPI1_Init(void)
{
hspi1.Instance = SPI1;
hspi1.Init.Mode = SPI_MODE_MASTER;
hspi1.Init.Direction = SPI_DIRECTION_2LINES;
hspi1.Init.DataSize = SPI_DATASIZE_8BIT;
hspi1.Init.CLKPolarity = SPI_POLARITY_LOW;
hspi1.Init.CLKPhase = SPI_PHASE_1EDGE;
hspi1.Init.NSS = SPI_NSS_SOFT;
hspi1.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_2;
hspi1.Init.FirstBit = SPI_FIRSTBIT_MSB;
hspi1.Init.TIMode = SPI_TIMODE_DISABLE;
hspi1.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
hspi1.Init.CRCPolynomial = 10;
if (HAL_SPI_Init(&hspi1) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
}
void HAL_SPI_MspInit(SPI_HandleTypeDef* spiHandle)
{
GPIO_InitTypeDef GPIO_InitStruct;
if(spiHandle->Instance==SPI1)
{
/* USER CODE BEGIN SPI1_MspInit 0 */
/* USER CODE END SPI1_MspInit 0 */
/* SPI1 clock enable */
__HAL_RCC_SPI1_CLK_ENABLE();
/**SPI1 GPIO Configuration
PB3 ------> SPI1_SCK
PB4 ------> SPI1_MISO
PB5 ------> SPI1_MOSI
*/
GPIO_InitStruct.Pin = GPIO_PIN_3|GPIO_PIN_4|GPIO_PIN_5;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF5_SPI1;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
/* USER CODE BEGIN SPI1_MspInit 1 */
/* USER CODE END SPI1_MspInit 1 */
}
}
void HAL_SPI_MspDeInit(SPI_HandleTypeDef* spiHandle)
{
if(spiHandle->Instance==SPI1)
{
/* USER CODE BEGIN SPI1_MspDeInit 0 */
/* USER CODE END SPI1_MspDeInit 0 */
/* Peripheral clock disable */
__HAL_RCC_SPI1_CLK_DISABLE();
/**SPI1 GPIO Configuration
PB3 ------> SPI1_SCK
PB4 ------> SPI1_MISO
PB5 ------> SPI1_MOSI
*/
HAL_GPIO_DeInit(GPIOB, GPIO_PIN_3|GPIO_PIN_4|GPIO_PIN_5);
/* USER CODE BEGIN SPI1_MspDeInit 1 */
/* USER CODE END SPI1_MspDeInit 1 */
}
}
/********************************************FLASH API********************************************************/
//函數功能: 從串行Flash讀取一個字節數據
uint8_t SPI_FLASH_ReadByte(void)
{
if(HAL_SPI_TransmitReceive(&hspi1,&d_send,&d_read,1,0xFFFFFF)!=HAL_OK)
d_read=0xff;
return d_read;
}
// 函數功能: 往串行Flash讀取寫入一個字節數據並接收一個字節數據
uint8_t SPI_FLASH_SendByte(uint8_t byte)
{
if(HAL_SPI_TransmitReceive(&hspi1,&byte,&d_read,1,0xFFFFFF)!=HAL_OK)
return 1;
return 0;
}
//讀取Flash ID
uint32_t SPI_FLASH_ReadID(void)
{
uint32_t Temp = 0, Temp0 = 0, Temp1 = 0, Temp2 = 0;
/* 選擇串行FLASH: CS低電平 */
FLASH_L
/* 發送命令：讀取芯片型號ID */
SPI_FLASH_SendByte(0x9F);
Temp0 = SPI_FLASH_ReadByte();
Temp1 = SPI_FLASH_ReadByte();
Temp2 = SPI_FLASH_ReadByte();
/* 禁用串行Flash：CS高電平 */
FLASH_H
Temp = (Temp0 << 16) | (Temp1 << 8) | Temp2;
return Temp;
}
//從Flash讀取數據
void SPI_FLASH_BufferRead(uint8_t* pBuffer, uint32_t ReadAddr, uint16_t NumByteToRead)
{
FLASH_L
SPI_FLASH_SendByte(0x03);
SPI_FLASH_SendByte((ReadAddr & 0xFF0000) >> 16);
SPI_FLASH_SendByte((ReadAddr & 0xFF00) >> 8);
SPI_FLASH_SendByte(ReadAddr & 0xFF);
while (NumByteToRead--) /* 讀取數據 */
{
*pBuffer = SPI_FLASH_ReadByte();
pBuffer++;
}
FLASH_H
}
void SPI_FLASH_PageWrite(uint8_t* pBuffer,uint32_t addr,uint16_t NumByteToRead)
{
uint16_t i;
SPI_FLASH_WriteEnable(); //SET WEL
FLASH_L
SPI_FLASH_SendByte(0x02);
SPI_FLASH_SendByte((uint8_t)((addr)>>16)); //發送24bit地址
SPI_FLASH_SendByte((uint8_t)((addr)>>8));
SPI_FLASH_SendByte((uint8_t)addr);
for(i=0;i<NumByteToRead;i++)
{
SPI_FLASH_SendByte(pBuffer[i]);//循環寫數
}
FLASH_H //取消片選
SPI_FLASH_WaitForWriteEnd(); //等待寫入結束
}
//FLASH寫函數
void SPI_FLASH_BufferWrite(uint8_t* pBuffer,uint32_t WriteAddr,uint32_t NumByteToWrite)
{
uint32_t pageremain;
pageremain=256-WriteAddr%256; //單頁剩餘的字節數
if(NumByteToWrite<=pageremain)pageremain=NumByteToWrite;//不大於256個字節
while(1)
{
SPI_FLASH_PageWrite(pBuffer,WriteAddr,pageremain);
if(NumByteToWrite==pageremain)break;//寫入結束了
else //NumByteToWrite>pageremain
{
pBuffer+=pageremain;
WriteAddr+=pageremain;
NumByteToWrite-=pageremain; //減去已經寫入了的字節數
if(NumByteToWrite>256)pageremain=256; //一次可以寫入256個字節
else pageremain=NumByteToWrite; //不夠256個字節了
}
}
}
/* 函數功能: 擦除扇區 */
void SPI_FLASH_SectorErase(uint32_t SectorAddr)
{
SPI_FLASH_WriteEnable();
SPI_FLASH_WaitForWriteEnd();
FLASH_L
SPI_FLASH_SendByte(0x20);
SPI_FLASH_SendByte((SectorAddr & 0xFF0000) >> 16);
SPI_FLASH_SendByte((SectorAddr & 0xFF00) >> 8);
SPI_FLASH_SendByte(SectorAddr & 0xFF);
FLASH_H
SPI_FLASH_WaitForWriteEnd();
}
/* 函數功能: 擦除整個芯片 */
void SPI_FLASH_BulkErase(void)
{
SPI_FLASH_WriteEnable();
FLASH_L
SPI_FLASH_SendByte(0xC7);
FLASH_H
SPI_FLASH_WaitForWriteEnd();
}
//寫使能
void SPI_FLASH_WriteEnable(void)
{
FLASH_L
SPI_FLASH_SendByte(0x06);
FLASH_H
}
//等待寫入完畢
void SPI_FLASH_WaitForWriteEnd(void)
{
uint8_t FLASH_Status = 0;
FLASH_L
SPI_FLASH_SendByte(0x05);
do
{
FLASH_Status = SPI_FLASH_ReadByte();
}
while ((FLASH_Status & 0x01) == SET);
FLASH_H
}
/**
* 函數功能: 進入掉電模式
* 輸入參數: 無
* 返 回 值: 無
* 說 明：無
*/
void SPI_Flash_PowerDown(void)
{
FLASH_L
SPI_FLASH_SendByte(0xB9);
FLASH_H
}
/**
* 函數功能: 喚醒串行Flash
* 輸入參數: 無
* 返 回 值: 無
* 說 明：無
*/
void SPI_Flash_WAKEUP(void)
{
FLASH_L
SPI_FLASH_SendByte(0xAB);
FLASH_H
}
/**
* @}
*/
/**
* @}
*/
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/SPI.H：
/**
******************************************************************************
* File Name : SPI.h
* Description : This file provides code for the configuration
* of the SPI instances.
******************************************************************************
* This notice applies to any and all portions of this file
* that are not between comment pairs USER CODE BEGIN and
* USER CODE END. Other portions of this file, whether
* inserted by the user or by software development tools
* are owned by their respective copyright owners.
*
* Copyright (c) 2018 STMicroelectronics International N.V.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted, provided that the following conditions are met:
*
* 1. Redistribution 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 other
* contributors to this software may be used to endorse or promote products
* derived from this software without specific written permission.
* 4. This software, including modifications and/or derivative works of this
* software, must execute solely and exclusively on microcontroller or
* microprocessor devices manufactured by or for STMicroelectronics.
* 5. Redistribution and use of this software other than as permitted under
* this license is void and will automatically terminate your rights under
* this license.
*
* THIS SOFTWARE IS PROVIDED BY STMICROELECTRONICS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS, IMPLIED OR STATUTORY WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NON-INFRINGEMENT OF THIRD PARTY INTELLECTUAL PROPERTY
* RIGHTS ARE DISCLAIMED TO THE FULLEST EXTENT PERMITTED BY LAW. IN NO EVENT
* SHALL STMICROELECTRONICS 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.
*
******************************************************************************
*/
/* Define to prevent recursive inclusion -------------------------------------*/
#ifndef __spi_H
#define __spi_H
#ifdef __cplusplus
extern "C" {
#endif
/* Includes ------------------------------------------------------------------*/
#include "stm32f4xx_hal.h"
#include "main.h"
#define FLASH_ID 0xEF4015
#define FLASH_L GPIOB->BSRR = GPIO_PIN_0<<16U;
#define FLASH_H GPIOB->BSRR = GPIO_PIN_0;
/* USER CODE BEGIN Includes */
/* USER CODE END Includes */
extern SPI_HandleTypeDef hspi1;
/* USER CODE BEGIN Private defines */
/* USER CODE END Private defines */
extern void _Error_Handler(char *, int);
void MX_SPI1_Init(void);
/* USER CODE BEGIN Prototypes */
/* USER CODE END Prototypes */
#ifdef __cplusplus
}
#endif
#endif /*__ spi_H */
/***************FLASH API******************/
uint32_t SPI_FLASH_ReadID(void);
void SPI_FLASH_BufferWrite(uint8_t* pBuffer,uint32_t WriteAddr,uint32_t NumByteToWrite);
void SPI_FLASH_BufferRead(uint8_t* pBuffer, uint32_t ReadAddr, uint16_t NumByteToRead);
void SPI_FLASH_PageWrite(uint8_t* pBuffer, uint32_t WriteAddr, uint16_t NumByteToWrite);
void SPI_FLASH_SectorErase(uint32_t SectorAddr);
void SPI_FLASH_BulkErase(void);
void SPI_FLASH_WriteEnable(void);
void SPI_FLASH_WaitForWriteEnd(void);
void SPI_Flash_PowerDown(void);
void SPI_Flash_WAKEUP(void);
/**
* @}
*/
/**
* @}
*/
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
SPI代碼，大部分用的是硬石的。我自己也有寫，但就是想試試別人的代碼。當然他代碼也存在一些問題，他沒有將
uint8_t SPI_FLASH_ReadByte(void);
uint8_t SPI_FLASH_SendByte(uint8_t byte);的功能區分開，導致這兩個函數實現一樣的功能（SPI寄存器數據迴環），我修改了一下，使它們讀寫功能分開，
而且更精簡一些。
void SPI_FLASH_BufferWrite(uint8_t* pBuffer,uint32_t WriteAddr,uint32_t NumByteToWrite);這個函數的是原子的，因爲硬石寫得太囉嗦 - . -
修改完SPI以及"usbd_storage_if.c"，編譯過後燒寫進芯片。
燒寫完後需要重新插拔USB，然後就會彈出新的U盤，你U盤中沒有文件系統的話，會要求你格式化的。結果如圖：
我的FLASH是W25Q16，所以顯示2MB容量。