DEVICEHIGH= (CONFIG.SYS Command)
Purpose: Loads a device driver into upper▲ memory on 386-based and better
Uses: Use to maximize the amount of conventional▲ memory available for
Use DEVICE= to install drivers into conventional▲ memory.
Syntax: DEVICEHIGH=[d:][path]filename.ext [drvrParms]
or: DEVICEHIGH [/L:loadOpts [/S]]=[d:][path]filename.ext [drvrParms]
d:\path\filename.ext is the drive, path, filename and extension of the file
that contains the device driver program code. If you omit the
drive and/or path, the file must be in the root of the boot disk.
The file usually has an extension of .SYS, .BIN, or .EXE and the
extension must be specified.
drvrParms are switches and options needed by the device driver. They vary
from driver to driver.
/L:loadOpts specifies a UMB region and minimum size needs for the driver.
/L and /S are normally used only by the Memmaker command when it
optimizes memory use in your CONFIG.SYS file.
When /L is omitted, DOS loads the driver into the largest
available UMB▲ region and gives it access to that entire region.
If no UMB is large enough for the driver, it is loaded into
For hand-optimizing the /L settings, the actual syntax is:
rgn is a UMB region number (0 to n; 0 is conventional▲ memory and
n varies depending upon your memory configuration. Use Mem
/F to obtain a list of free UMB regions on your system).
minSize specifies the amount of memory that the driver will need.
It is used for cases when the driver needs more memory than
is identified by the load module.
;rgn[,minSize]... When a driver can make use of more than one
memory block, you can specify additional regions and sizes
on the command line.
/S may be used in conjunction with /L. It is normally used only by
Memmaker, after it analyses the driver's use of memory. It
causes DOS to shrink the specified UMB to a smaller size,
thereby minimizing driver memory use.
■ When this is used, DOS has set the allocation strategy to
FIRST_FIT_HIGH as it loads the driver. See DOS fn 58H for related
■ If your device driver allocates memory and you wish to direct where
that memory will be, use fns 5803H and 5801H.
See Also: CONFIG.SYS Commands