fs(4) — UTek 4.0



FS(4)                   COMMAND REFERENCE                   FS(4)



NAME
     fs - standard floppy disk driver for SCSI floppy disk drives

DESCRIPTION
     The fs device provides access to the standard flexible disk
     drive. It uses 5 1/4 inch, double-sided, double- or high-
     density, soft-sectored, pre-formatted flexible disks. The
     characteristics of the two supported media are:

           Type               Double-density   High-density
           ________________________________________________
           tracks/inch                 4              96
           bytes/sector              512             512
           sectors/track               9              15
           tracks/side                40              80
           sides/diskette              2               2
           bytes/diskette         368640         1228800
           sectors/diskette          720            2400

     Both formats are compatible with the de facto industry
     standard for Personal Computing media.

     When the fs device is opened, UTek tests the diskette to see
     whether it is formatted as a double-density or high-density
     medium. It performs all operations on the diskette in the
     appropriate mode, until the device is reopened.  If the
     diskette is not formatted, only the whole disk partition may
     be opened, and the only operation allowed is formatting.

     The standard name for the flexible disk is fs02. Device
     naming conventions specify a two-letter description of the
     device, followed by the slot number, followed by the device
     number. The slot number for the standard floppy disk drive
     is 0 since its SCSI interface is on the main board. The
     device number for the standard floppy disk drive is 2 since
     it is configured as the first unit at SCSI bus address 1.

     Although floppy disks are not actually partitioned, they are
     accessed as if they follow the partitioning scheme for hard
     disks. Only partitions  a  and  p  (appended to the device
     name) are accessible.  Partition  a  refers to all of the
     data space and is used for all normal data operations.
     Partition  p  refers to the whole disk and is used for
     formatting operations.

     The flexible disk may only be accessed in character (raw)
     mode.  The character device name is the standard name with
     an  r  prefixed.  Standard device names rdf and IB rdfp are
     linked to rfs02a and rfs02p, respectively, for ease of use
     and compatibility with previous UTek products.





Printed 4/6/89                                                  1



FS(4)                   COMMAND REFERENCE                   FS(4)



     Use scsifmt(8) on /dev/rdfp to format floppy disks.  This
     can be done at any time.

     UTek does not support access to the block floppy device due
     to concerns for system integrity.

FILES
     /dev/rfs02a, /dev/rdf
                       raw files

     /dev/rfs02p, /dev/rdfp
                       formatting

     /dev/fs02a, /dev/df
                       block files

DIAGNOSTICS
     The following errors may be returned.

     [EBUSY] Drive not ready (on a read or write).

     [ENXIO] Nonexistent drive (on open); or (on a read or write)
             offset is too large or not on a sector boundary.

     [EIO]   A physical error other than ``not ready''.

CAVEATS
     Due to limitations of the electrical interface between the
     controller and drive, the fs driver is unable to determine
     directly what capacity drive or floppy disk is being used.
     Operation mistakes such as formatting a high-density
     diskette as double-density or vice versa can't be prevented.
     The former mistake will lose capacity; the latter will lose
     data integrity or create data errors.

     The only way that the driver can determine capacity is to
     examine the readability of the formatted diskette.

     The high-capacity floppy drives shipped as the standard
     floppy drive on all workstations with a standard SCSI
     interface are capable of reliably reading and writing
     double- and high-density diskettes.  Due to limitations of
     the electromechanical design of the high-capacity drives,
     standard (360K only) drives can't reliably read double-
     density (360K) diskettes written by such drives.

SEE ALSO
     ds(4), and scsifmt(8).







Printed 4/6/89                                                  2

%%index%%
na:192,112;
de:304,2985;3553,229;
fi:3782,329;
di:4111,404;
ca:4515,1065;
se:5580,133;
%%index%%000000000120

Museum

Related Articles