DPARAM(C) XENIX System V DPARAM(C)
Name
dparam - Displays/changes hard disk characteristics.
Syntax
dparam [ -w ]
dparam /dev/rhd[01]0 [characteristics]
Description
The dparam command displays or changes the hard disk
characteristics currently in effect. These changes go into
effect immediately and are also written to the master boot
block for subsequent boots. If a non-standard hard disk is
used, this utility must be called before accessing the
drive.
-w Causes a copy of /etc/masterboot to be copied to
disk to ensure that non-standard hard disks are
supported for the specified drive. This call must
precede a call to write non-standard disk parameters
for the desired parameters to be saved correctly in
the masterboot block.
When called without options or disk characteristics, dparam
prints the current disk characteristics (on the standard
output) for the specified hard disk. These values are
printed in the same order as the argument list.
When writing characteristics for the specified hard disk,
dparam changes the current disk controller status and
updates the masterboot block. The argument ordering is
critical and must be entered as specified below. All
characteristics must be entered when writing disk
characteristics, otherwise an error is returned. Hard disk
characteristics (in respective order) are:
number of cylinders total number of
cylinders on the hard
disk
number of heads number of heads
write cylinder hardware specific,
consult your hardware
manual
write precompensation cylinder hardware specific,
consult your hardware
manual
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DPARAM(C) XENIX System V DPARAM(C)
ecc number of bits of
error correction on
I/O transfers, consult
your hardware manual
control very hardware
specific, consult your
hardware manual
landing zone cylinder where to park heads
after shutting down
the system
number of sectors per track number of sectors per
track on the hard disk
Examples
dparam -w
dparam /dev/rhd10
dparam /dev/rhd00 700 4 256 180 5 0 640 17
Notes
This utility changes the kernel's view of the hard disk
parameters. It may be subject to restrictions imposed by the
hardware configuration.
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