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那位大神知道在移植 Fatfs时候是如何加载分区表的,
f_mount(0, &g_fs); /* Mount a logical drive */ //只是将文件系统的结构体指针指向对象
实际将U盘数据挂载到 这个结构体是怎样操作的?
/* File system object structure (FATFS) */
typedef struct {
BYTE fs_type; /* FAT sub-type (0:Not mounted) */
BYTE drv; /* Physical drive number */
BYTE csize; /* Sectors per cluster (1,2,4...128) */
BYTE n_fats; /* Number of FAT copies (1,2) */
BYTE wflag; /* win[] dirty flag (1:must be written back) */
BYTE fsi_flag; /* fsinfo dirty flag (1:must be written back) */
WORD id; /* File system mount ID */
WORD n_rootdir; /* Number of root directory entries (FAT12/16) */
#if _MAX_SS != 512
WORD ssize; /* Bytes per sector (512, 1024, 2048 or 4096) */
#endif
#if _FS_REENTRANT
_SYNC_t sobj; /* Identifier of sync object */
#endif
#if !_FS_READONLY
DWORD last_clust; /* Last allocated cluster */
DWORD free_clust; /* Number of free clusters */
DWORD fsi_sector; /* fsinfo sector (FAT32) */
#endif
#if _FS_RPATH
DWORD cdir; /* Current directory start cluster (0:root) */
#endif
DWORD n_fatent; /* Number of FAT entries (= number of clusters + 2) */
DWORD fsize; /* Sectors per FAT */
DWORD volbase; /* Volume start sector */
DWORD fatbase; /* FAT start sector */
DWORD dirbase; /* Root directory start sector (FAT32:Cluster#) */
DWORD database; /* Data start sector */
DWORD winsect; /* Current sector appearing in the win[] */
BYTE win[_MAX_SS]; /* Disk access window for Directory, FAT (and Data on tiny cfg) */
} FATFS;
/* File object structure (FIL) */
typedef struct {
FATFS* fs; /* Pointer to the related file system object (**do not change order**) */
WORD id; /* Owner file system mount ID (**do not change order**) */
BYTE flag; /* File status flags */
BYTE pad1;
DWORD fptr; /* File read/write pointer (0ed on file open) */
DWORD fsize; /* File size */
DWORD sclust; /* File data start cluster (0:no data cluster, always 0 when fsize is 0) */
DWORD clust; /* Current cluster of fpter */
DWORD dsect; /* Current data sector of fpter */
#if !_FS_READONLY
DWORD dir_sect; /* Sector containing the directory entry */
BYTE* dir_ptr; /* Pointer to the directory entry in the window */
#endif
#if _USE_FASTSEEK
DWORD* cltbl; /* Pointer to the cluster link map table (null on file open) */
#endif
#if _FS_LOCK
UINT lockid; /* File lock ID (index of file semaphore table Files[]) */
#endif
#if !_FS_TINY
BYTE buf[_MAX_SS]; /* File data read/write buffer */
#endif
} FIL; |
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