STM32F FREERTOS SPI-FLASH FATFS可以写文件，无法打开文件或者无法读文件的问题
这两天终于把SPI FLASH的FATFS文件系统搞好了。总结这一过程，得出以下经验：
1. 先将SPI FALSH底层驱动调好，并好好做测试。自己写一个程序，写入然后读出进行校验，确认数据是OK，并且确认整片FLASH是可用的。 之前驱动没写好，PAGE和SECTOR搞错了，导致部分文件只能写入一部分，后面部分不正确，一开始还以为是内存异常，找了好久。
2. user_diskio.c文件里的USER_initialize、USER_status、USER_read、USER_write这4大函数，一定要写好。前面2个函数没什么，主要是后面两个函数容易出错，或者容易让人大意出问题。因为USER_read和USER_write这两个函数传递进来的sector就是扇区（@param sector: Sector address (LBA)），而不是扇区地址。而底层驱动（我从网上下载的）采用的是扇区所在的物理地址，两种要做好对应关系。否则，可能出现可以绑定、但是无法读写的情况。
3. USER_ioctl函数中，获取命令为GET_BLOCK_SIZE是，根据字面理解返回的是块的长度尺寸，例如64K，但是应该返回的是块里面扇区的数量。
4. 第一次使用FLASH或上电需要格式化文件系统，这个是常识了，当然过后就不再需要了，除非FLASH出现异常。发现网上有人提出问题无法保存数据的问题，结果是每次上电都格式化了。res = f_mkfs(USERPath, 1, 4096);
注意以上问题后，FATFS就可以用了。
相关代码：
/**
******************************************************************************
* @file user_diskio.c
* @brief This file includes a diskio driver skeleton to be completed by the user.
******************************************************************************
* 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.
*
******************************************************************************
*/
#ifdef USE_OBSOLETE_USER_CODE_SECTION_0
/*
* Warning: the user section 0 is no more in use (starting from CubeMx version 4.16.0)
* To be suppressed in the future.
* Kept to ensure backward compatibility with previous CubeMx versions when
* migrating projects.
* User code previously added there should be copied in the new user sections before
* the section contents can be deleted.
*/
/* USER CODE BEGIN 0 */
/* USER CODE END 0 */
#endif
/* USER CODE BEGIN DECL */
/* Includes ------------------------------------------------------------------*/
#include
#include "ff_gen_drv.h"
#include "w25qx.h"
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Disk status */
static volatile DSTATUS Stat = STA_NOINIT;
extern void MX_SPI1_Init(void);
/* USER CODE END DECL */
/* Private function prototypes -----------------------------------------------*/
DSTATUS USER_initialize (BYTE pdrv);
DSTATUS USER_status (BYTE pdrv);
DRESULT USER_read (BYTE pdrv, BYTE *buff, DWORD sector, UINT count);
#if _USE_WRITE == 1
DRESULT USER_write (BYTE pdrv, const BYTE *buff, DWORD sector, UINT count);
#endif /* _USE_WRITE == 1 */
#if _USE_IOCTL == 1
DRESULT USER_ioctl (BYTE pdrv, BYTE cmd, void *buff);
#endif /* _USE_IOCTL == 1 */
Diskio_drvTypeDef USER_Driver =
{
USER_initialize,
USER_status,
USER_read,
#if _USE_WRITE
USER_write,
#endif /* _USE_WRITE == 1 */
#if _USE_IOCTL == 1
USER_ioctl,
#endif /* _USE_IOCTL == 1 */
};
/* Private functions ---------------------------------------------------------*/
/**
* @brief Initializes a Drive
* @param pdrv: Physical drive number (0..)
* @retval DSTATUS: Operation status
*/
DSTATUS USER_initialize (
BYTE pdrv /* Physical drive nmuber to identify the drive */
)
{
switch (pdrv)
{
case 0 :
MX_SPI1_Init(); //初始化SPI FLASH
return RES_OK;
case 1 :
return RES_OK;
case 2 :
return RES_OK;
case 3 :
return RES_OK;
default:
return STA_NOINIT;
}
}
/**
* @brief Gets Disk Status
* @param pdrv: Physical drive number (0..)
* @retval DSTATUS: Operation status
*/
DSTATUS USER_status (
BYTE pdrv /* Physical drive number to identify the drive */
)
{
switch (pdrv)
{
case 0 :
return RES_OK;
case 1 :
return RES_OK;
case 2 :
return RES_OK;
default:
return STA_NOINIT;
}
}
/**
* @brief Reads Sector(s)
* @param pdrv: Physical drive number (0..)
* @param *buff: Data buffer to store read data
* @param sector: Sector address (LBA)
* @param count: Number of sectors to read (1..128)
* @retval DRESULT: Operation result
*/
DRESULT USER_read (
BYTE pdrv, /* Physical drive nmuber to identify the drive */
BYTE *buff, /* Data buffer to store read data */
DWORD sector, /* Sector address in LBA */
UINT count /* Number of sectors to read */
)
{
/* USER CODE HERE */ //HUANGDADAO
UINT i = 0;
for(i = 0; i < count; i ++)
{
BSP_W25Qx_Read_Sector(buff, sector*SECTOR_SIZE);
sector++;
buff+=SECTOR_SIZE;
}
return RES_OK;
}
/**
* @brief Writes Sector(s)
* @param pdrv: Physical drive number (0..)
* @param *buff: Data to be written
* @param sector: Sector address (LBA)
* @param count: Number of sectors to write (1..128)
* @retval DRESULT: Operation result
*/
#if _USE_WRITE == 1
DRESULT USER_write (
BYTE pdrv, /* Physical drive nmuber to identify the drive */
const BYTE *buff, /* Data to be written */
DWORD sector, /* Sector address in LBA */
UINT count /* Number of sectors to write */
)
{
/* USER CODE HERE */
UINT i = 0;
for(i = 0; i < count; i ++)
{
BSP_W25Qx_Write_Sector((uint8_t*)buff,sector*SECTOR_SIZE);
sector ++;
buff += SECTOR_SIZE;
}
return RES_OK;
}
#endif /* _USE_WRITE == 1 */
/**
* @brief I/O control operation
* @param pdrv: Physical drive number (0..)
* @param cmd: Control code
* @param *buff: Buffer to send/receive control data
* @retval DRESULT: Operation result
*/
#if _USE_IOCTL == 1
DRESULT USER_ioctl (
BYTE pdrv, /* Physical drive nmuber (0..) */
BYTE cmd, /* Control code */
void *buff /* Buffer to send/receive control data */
)
{
DRESULT res = RES_OK;
switch(cmd)
{
case CTRL_SYNC :
break;
case CTRL_TRIM:
break;
case GET_BLOCK_SIZE:
*(DWORD*)buff = BLOCK_SIZE;
break;
case GET_SECTOR_SIZE:
*(DWORD*)buff = SECTOR_SIZE;
break;
case GET_SECTOR_COUNT:
*(DWORD*)buff = SECTOR_COUNT;
break;
default:
res = RES_PARERR;
break;
}
return res;
}
#endif /* _USE_IOCTL == 1 */
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/