The FATFS structure (file system object) holds dynamic work area of individual logical drives. It is given by application program and registerd/unregisterd to the FatFs module with f_mount() function. Initialization is done on first API call after f_mount() function or media change. Application program must not modify any member in this structure.
++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[] flag (b0:win[] is dirty) */ + BYTE fsi_flag; /* FSINFO flags (b7:Disabled, b0:Dirty) */ + WORD id; /* File system mount ID */ + WORD n_rootdir; /* Number of root directory entries (FAT12/16) */ +#if _MAX_SS != _MIN_SS + WORD ssize; /* Sector size (512,1024,2048 or 4096) */ +#endif +#if _FS_REENTRANT + _SYNC_t sobj; /* Identifier of sync object */ +#endif +#if !_FS_READONLY + DWORD last_clust; /* FSINFO: Last allocated cluster */ + DWORD free_clust; /* FSINFO: Number of free clusters */ +#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 area start sector */ + DWORD dirbase; /* Root directory area start sector (FAT32: Cluster#) */ + DWORD database; /* Data area start sector */ + DWORD winsect; /* Current sector appearing in the win[] */ + BYTE win[_MAX_SS]; /* Disk access window for directory, FAT (and file data at tiny cfg) */ +} FATFS; ++