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(fdutils.info)Timing parameters

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Timing Parameters
-----------------

   This section describes how to configure drive timings.  To set these
parameters, you need superuser privileges. All times are in "jiffy"
units (10 milliseconds), unless otherwise specified.

`--hlt  HLT'
     Set the head load time (in microseconds) for this floppy drive.
     The head load time describes how long the floppy controller waits
     after seeking or changing heads before allowing access to a track.

`--hut  HUT'
     Set the head unload time (in microseconds) for this floppy drive.
     The head unload time describes how long the floppy controller
     waits after an access before directing its attention to the other
     head, or before seeking.

`--srt  SRT'
     Set the step rate (in microseconds) for this floppy drive.  The
     step rate describes how long the drive head stays on one cylinder
     when seeking.  Setting this value to low (too fast seeks) may make
     seeks fail, because the motor doesn't follow fast enough.

`-u SPINUP-TIME'
`--spinup  SPINUP-TIME'
     Set the spinup time of the floppy drive. In order to do read or
     write to the floppy disk, it must spin. It takes a certain time
     for the motor to reach enough speed to read or write. This
     parameter describes this time. The floppy driver doesn't try to
     access the drive before the spinup time has elapsed. With modern
     controllers, you may set this time to zero, as the controller
     itself enforces the right delay.

`-o SPINDOWN-TIME'
`--spindown  SPINDOWN-TIME'
     Set the spindown time of this floppy drive. The motor is not
     stopped immediately after the operation completes, because there
     might be more operations following. The spindown time is the time
     the driver waits before switching off the motor.

`-O SPINDOWN-OFFSET'
`--spindown_offset  SPINDOWN-OFFSET'
     Set the spindown offset of this floppy drive. This parameter is
     used to set the position in which the disk stops. This is useful to
     minimize the next access time. (If the first sector is just near
     the head at the very moment at which the disk has reached enough
     speed, you win 200 milliseconds against the most unfavorable
     situation).

     This is done by clocking the time where the first I/O request
     completes, and using this time to calculate the current position of
     the disk.

`-s SELECT-DELAY'
`--select_delay  SELECT-DELAY'
     Set the SELECT DELAY of this floppy drive. This is the delay that
     the driver waits after selecting the drive and issuing the first
     command to it. For modern controllers/drives, you may set this to
     zero.

`-C CHECK-INTERVAL'
`--checkfreq  CHECK-INTERVAL'
     Set the maximal disk change check interval.  The disk change line
     is checked whenever a read or write to the device is issued, and
     it has not been checked for more than INTERVAL jiffies.