Provided by: fdutils_5.5-20060227-6_amd64 bug

NAME

       fd - floppy disk device

CONFIGURATION

       Floppy  drives  are  block  devices  with  major  number  2.   Typically they are owned by
       root.floppy and have either mode 0660 (access checking via group membership) or mode  0666
       (everybody  has  access).   For the following devices, n is the drive number.  It is 0 for
       the first drive, 1 for the second etc.  To  get  a  minor  number  for  a  specific  drive
       connected  to the first controller, add n to the minor base number.  If it is connected to
       the second controller, add n+128 to the minor base number.  Warning: If  you  use  formats
       with  more  tracks  than  supported by your drive, you may damage it mechanically.  Trying
       once if more tracks than the usual 40/80 are  supported  should  not  damage  it,  but  no
       warranty  is  given  for  that.   Don't create device entries for those formats to prevent
       their usage if you are not sure.

       Drive independent device files which automatically detect the media format and capacity:

       Name   Base minor #
       ────────────────────
       fdn    0

       5.25 inch double density device files:

       Name         Capac.   Cyl.   Sect.   Heads   Base minor #
       ──────────────────────────────────────────────────────────
       fdnd360      360K     40     9       2       4

       5.25 inch high density device files:

       Name         Capac.   Cyl.   Sect.   Heads   Base minor #
       ──────────────────────────────────────────────────────────
       fdnh360      360K     40     9       2       20
       fdnh410      410K     41     10      2       48
       fdnh420      420K     42     10      2       64
       fdnh720      720K     80     9       2       24
       fdnh880      880K     80     11      2       80
       fdnh1200     1200K    80     15      2       8
       fdnh1440     1440K    80     18      2       40
       fdnh1476     1476K    82     18      2       56
       fdnh1494     1494K    83     18      2       72
       fdnh1600     1600K    80     20      2       92

       3.5 inch double density device files:

       Name         Capac.   Cyl.   Sect.   Heads   Base minor #
       ──────────────────────────────────────────────────────────
       fdnu360      360K     80     9       1       12
       fdnu720      720K     80     9       2       16
       fdnu800      800K     80     10      2       120
       fdnu1040     1040K    80     13      2       84
       fdnu1120     1120K    80     14      2       88

       3.5 inch high density device files:

       Name         Capac.   Cyl.   Sect.   Heads   Base minor #
       ──────────────────────────────────────────────────────────
       fdnu360      360K     40     9       2       12
       fdnu720      720K     80     9       2       16
       fdnu820      820K     82     10      2       52
       fdnu830      830K     83     10      2       68
       fdnu1440     1440K    80     18      2       28

       fdnu1600     1600K    80     20      2       124
       fdnu1680     1680K    80     21      2       44
       fdnu1722     1722K    82     21      2       60
       fdnu1743     1743K    83     21      2       76
       fdnu1760     1760K    80     22      2       96
       fdnu1840     1840K    80     23      2       116
       fdnu1920     1920K    80     24      2       100

       3.5 inch extra density device files:

       Name         Capac.   Cyl.   Sect.   Heads   Base minor #
       ──────────────────────────────────────────────────────────
       fdnu2880     2880K    80     36      2       32
       fdnu3200     3200K    80     40      2       104
       fdnu3520     3520K    80     44      2       108
       fdnu3840     3840K    80     48      2       112

DESCRIPTION

       fd special files access the floppy disk drives in raw mode.  The following ioctl(2)  calls
       are supported by fd devices:

       FDCLRPRM
              clears the media information of a drive (geometry of disk in drive).

       FDSETPRM
              sets  the media information of a drive. The media information will be lost when the
              media is changed.

       FDDEFPRM
              sets the media information of a drive  (geometry  of  disk  in  drive).  The  media
              information  will  not  be  lost  when  the  media  is  changed.  This will disable
              autodetection. In order to re-enable autodetection, you have to issue an FDCLRPRM .

       FDGETDRVTYP
              returns the type of a drive (name parameter).  For formats which  work  in  several
              drive  types,  FDGETDRVTYP returns a name which is appropriate for the oldest drive
              type which supports this format.

       FDFLUSH
              invalidates the buffer cache for the given drive.

       FDSETMAXERRS
              sets  the  error  thresholds  for  reporting  errors,   aborting   the   operation,
              recalibrating, resetting, and reading sector by sector.

       FDSETMAXERRS
              gets the current error thresholds.

       FDGETDRVTYP
              gets the internal name of the drive.

       FDWERRORCLR
              clears the write error statistics.

       FDWERRORGET
              reads  the  write error statistics. These include the total number of write errors,
              the location and disk of the first write error, and the location and  disk  of  the
              last  write error. Disks are identified by a generation number which is incremented
              at (almost) each disk change.

       FDTWADDLE
              Switch the drive motor off for a few microseconds. This might be needed in order to
              access a disk whose sectors are too close together.

       FDSETDRVPRM
              sets various drive parameters.

       FDGETDRVPRM
              reads these parameters back.

       FDGETDRVSTAT
              gets the cached drive state (disk changed, write protected et al.)

       FDPOLLDRVSTAT
              polls the drive and return its state.

       FDGETFDCSTAT
              gets the floppy controller state.

       FDRESET
              resets the floppy controller under certain conditions.

       FDRAWCMD
              sends a raw command to the floppy controller.

       For  more  precise  information, consult also the <linux/fd.h> and <linux/fdreg.h> include
       files, as well as the manual page for floppycontrol.

NOTES

       The various formats allow to read and write many types of disks.  However, if a floppy  is
       formatted  with  a  too  small inter sector gap, performance may drop, up to needing a few
       seconds to access an entire track. To prevent this, use interleaved  formats.  It  is  not
       possible  to  read floppies which are formatted using GCR (group code recording), which is
       used by Apple II and Macintosh computers (800k disks).  Reading floppies  which  are  hard
       sectored  (one  hole  per  sector,  with  the  index  hole  being  a little skewed) is not
       supported.  This used to be common with older 8 inch floppies.

FILES

       /dev/fd*

AUTHORS

       Alain   Knaff   (Alain@linux.lu),   David   Niemi   (niemidc@tux.org),   Bill   Broadhurst
       (bbroad@netcom.com).

SEE ALSO

       floppycontrol(1), mknod(1), chown(1), getfdprm(1), superformat(1), mount(8), setfdprm(1)