FATFS

FATFS構造体は、個々の論理ドライブのダイナミック・ワーク・エリアを保持し、f_mount()でFatFsモジュールに登録されます。標準状態では次のようなメンバになっています。アプリケーションから書き換え可能なメンバはありません。

FatFs

typedef struct _FATFS {
    WORD    id;             /* File system mount ID */
    WORD    n_rootdir;      /* Number of root directory entries */
    DWORD   winsect;        /* Current sector appearing in the win[] */
    DWORD   sects_fat;      /* Sectors per fat */
    DWORD   max_clust;      /* Maximum cluster# + 1 */
    DWORD   fatbase;        /* FAT start sector */
    DWORD   dirbase;        /* Root directory start sector (cluster# for FAT32) */
    DWORD   database;       /* Data start sector */
    DWORD   last_clust;     /* Last allocated cluster */
    DWORD   free_clust;     /* Number of free clusters */
    BYTE    fs_type;        /* FAT type (0:Not mounted) */
    BYTE    sects_clust;    /* Sectors per cluster */
    BYTE    n_fats;         /* Number of FAT copies */
    BYTE    drive;          /* Physical drive number */
    BYTE    winflag;        /* win[] dirty flag (1:must be written back) */
    BYTE    pad1;
    BYTE    win[512];       /* Disk access window for Directory/FAT */
} FATFS;

Tiny-FatFs

typedef struct _FATFS {
    WORD    id;             /* File system mount ID */
    WORD    n_rootdir;      /* Number of root directory entries */
    DWORD   winsect;        /* Current sector appearing in the win[] */
    DWORD   fatbase;        /* FAT start sector */
    DWORD   dirbase;        /* Root directory start sector */
    DWORD   database;       /* Data start sector */
    CLUST   sects_fat;      /* Sectors per fat */
    CLUST   max_clust;      /* Maximum cluster# + 1 */
    CLUST   last_clust;     /* Last allocated cluster */
    CLUST   free_clust;     /* Number of free clusters */
    BYTE    fs_type;        /* FAT type (0:Not mounted) */
    BYTE    sects_clust;    /* Sectors per cluster */
    BYTE    n_fats;         /* Number of FAT copies */
    BYTE    winflag;        /* win[] dirty flag (1:must be written back) */
    BYTE    win[512];       /* Disk access window for Directory/FAT/File */
} FATFS;