dparam(ADM) 19 June 1992 dparam(ADM) Name dparam, dkinit - display/change hard disk characteristics Syntax dparam [ -w ] dparam /dev/rhd[0|1]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. (dkinit provides a menu-driven front end to dparam. For full details on the use of dkinit, please refer to the System Administrator's Guide.) -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 reduced write current cylinder hardware specific, consult your hardware manual write precompensation cylinder hardware specific, consult your hardware manual ecc number of bits of error correction on I/O transfers, consult your hardware manual control 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. Value added dparam is an extension of AT&T System V provided by The Santa Cruz Opera- tion, Inc.