Command: sys / sys config
SYS makes a floppy disk or hard disk or another writable medium
bootable. SYS CONFIG configures the FreeDOS KERNEL.
Syntax:
SYS [source] drive: [bootsect] [{option}]
SYS [/?]
source = A:,B:,C:\KERNEL\BIN\,etc., The (optional) location of
the system files. If not given, the current directory
is assumed.
drive = A,B,C etc. The drive to make bootable.
bootsect The name of the 512-byte boot sector file image for drive:
to write to *instead* of real boot sector.
SYS CONFIG [drive][path]kernel.sys [option=value...]
SYS CONFIG [/help][/?]
SYS CONFIG
This will simply display the current settings for the file
KERNEL.SYS in the current directory. It is useful to see what
the options are currently set to, what options are supported,
and should show valid values along with defaults (defaults are
the valid values with a '*' next to them).
SYS CONFIG [drive][path]KERNEL.SYS
This form behaves as above, except will display the settings
for the kernel file you specify. Drive and path are optional,
and generally just a '\' will be used to indicate root directory
of current drive. KERNEL.SYS specifies the filename of the
kernel, which may not be "KERNEL.SYS", for example when testing
you want to alter KERNTEST.SYS and later copy (or rename) this
to KERNEL.SYS for booting.
Options:
SYS OPTIONS:
/BOTH The new boot sector will be written to the image file
and to the actual drive boot sector.
/BOOTONLY The boot sector (or image) will be updated, but the
KERNEL and COMMAND.COM will not be copied to the
destination.
/UPDATE Copy KERNEL and update boot sector (do *not* copy shell).
/OEM[:AUTO] Indicates boot sector, filenames, and load segment
to use.
/OEM:DE Use DEll Real Mode Kernel settings.
/OEM:DR Use DR DOS 7+ compatible settings.
/OEM:EDR Use Enhanced DR DOS 7+ compatible settings.
/OEM:FD Use FreeDOS compatible settings.
/OEM:MS Use MS-DOS compatible settings.
/OEM:PC Use PC-DOS compatible settings.
/OEM:Rx Use RxDOS compatible settings
/OEM:W9x Use MS Win9x DOS compatible settings.
Default is /OEM[:AUTO], select DOS based on existing
files.
/K name Gives the filename of the kernel file to be copied.
This option is only required when the kernel is not
called "kernel.sys"
/L segm The load segment, in hexadecimal, to use. The default
is 60.
/B btdrv : hex BIOS # of boot drive set in bs, 0=A:, 80=1st hd,...
/FORCE Override automatic selection of BIOS related settings.
/FORCE:AUTO Select LBA or CHS depending on BIOS availability.
/FORCE:BIOSDRV Use boot drive # provided by BIOS.
/FORCE:BSDRV Use boot drive # set in bootsector.
/FORCE:LBA Always use LBA.
/FORCE:CHS Always use CHS.
/NOBAKBS Skips copying boot sector to backup bs, FAT32 only
else ignored.
/SKFN filename Copy from filename to KERNEL.SYS; settings
same as /OEM:FD.
/SCFN filename Copy from filename to COMMAND.COM.
/BACKUPBS [path]filename Save current bs before overwriting.
/DUMPBS [path]filename Save current bs and exit.
/RESTORBS [path]filename Overwrite bs and exit.
/VERBOSE Display additional (debug) output.
/help Shows the help.
/? Shows the help.
SYS CONFIG OPTIONS:
/help Shows the help.
/? Shows the help.
Current options are:
DLASORT=0|1
This option is for specifying whether Drive Letter Assignment
should follow the normal MSDOS way of all primary partitions
across drives and then extended partitions, or the more logical
all partitions (primary and extended) on the 1st drive, then
repeat for all following drives (all primary and extended, then
try next drive). 0 corresponds to MS way and 1 corresponds to
first drive completely, then next ...
SHOWDRIVEASSIGNMENT=0|1
If 1 then the normal drive assignment information is displayed
upon booting. If 0 then this information is suppressed (not shown).
SKIPCONFIGSECONDS=# (maybe -128 to 127)
A negative value ( < 0 ) indicates that F5/F8 processing will
be skipped (the kernel won't check if you pressed these keys,
so you can't skip config file (CONFIG.SYS) processing). A 0
means you must have pressed the key precisely for when the
kernel checks for it - essentially skipping, though a well timed
finger will still get to use it. And any value greater than 0
is the number of seconds the kernel will display the prompt and
wait for you to press the key before assuming you didn't.
FORCELBA=0|1
If 1 then the kernel will use LBA (extended INT13) techniques
to address all partitions if possible, even if these have a
non-LBA partition type and are completely below cylinder 1023
(usually the 8GB boundary). This is 0 by default, for compati-
bility reasons. Setting this to 1 may bypass some buggy
BIOSes and gives slightly better performance.
GLOBALENABLELBASUPPORT=0|1
If 0 then LBA will be completely disabled, irrespective of the
FORCELBA setting. You need this if FreeDOS thinks you have LBA
available, but in reality you do not. This setting is set to
1 by default.
For more information about SYS CONFIG see:
http://www.fdos.org/kernel/.
Comments:
SYS:
The SYS command creates a bootsector on sector 0 of the diskette or
harddrive. Then it copies KERNEL.SYS and COMMAND.COM to the medium.
After this the computer is able to boot FreeDOS from this medium.
SYS CONFIG:
If no options are given, the current values are shown. /help or /?
displays the usage information. [drive][path]kernel.sys specifies the
kernel file to modify, if not given defaults to KERNEL.SYS.
Option=value ... specifies one or more options and the values to
set each to. If an option is given multiple times, the value set will
be the rightmost one.
Examples:
sys c: (from a diskette; the sys command and COMMAND.COM and KERNEL.SYS
should be on the diskette, after the execution the HD will be
bootable)
sys a: (from a HD or CD; the sys command and COMMAND.COM and KERNEL.SYS
should be on the source drive, after the execution the diskette
will be bootable)
See also:
command.com
format
fdisk
kernel
kernel-devel
label
vol
Copyright © 1998 Jim Hall, updated 2007 and 2020 by W. Spiegl.
This file is derived from the FreeDOS Spec Command HOWTO.
See the file H2Cpying for copying conditions.