Command: himemx
HIMEMX is the extended memory host for DOS (coordinates the usage of
XMS and HMA). HIMEMX has to be loaded in CONFIG.SYS / FDCONFIG.SYS.
Please place DEVICE=HIMEMX.EXE [options] before any driver using XMS.
Syntax:
HIMEMX [/MAX=####] [/METHOD:xxx] [/HMAMIN=n] [/NUMHANDLES=m]
[/VERBOSE] [/NOABOVE16] [/X] [/XMAX32]
Options:
/MAX=##### Limit memory controlled by XMM to ##### KB.
/METHOD:xxx Specifies the method to be used for A20 handling.
Possible values for xxx:
ALWAYSON Assume that A20 line is permanently ON
BIOS Use BIOS to toggle the A20 line
FAST Use port 92h, bypass INT 15h test
PS2 Use port 92h, bypass PS/2 test
KBC Use the keyboard controller
PORT92 Use port 92h always
/HMAMIN=n Specifies minimum number of KBs of HMA that a program
must request to gain access to the HMA (def: 0 KB).
/NUMHANDLES=m Number of XMS handles available (default: 48, min: 8,
max:128).
/VERBOSE Gives extra information.
/NOABOVE16 Do not use INT 15h function E801h to detect > 64 MB.
/X Do not use INT 15h function E820h to detect > 64 MB.
/X2MAX32 Limit XMS 2.0 free/avail. memory report to 32 MB-1 KB.
/? Shows the help.
Comments:
HIMEMX requires a 80386+ CPU. JEMM386 can be loaded after this
driver. Load HIMEMX as DEVICE=HIMEMX.EXE in CONFIG.SYS / FDCONFIG.SYS
(although it is an ".exe"-file!
For more informations see:
https://github.com/Baron-von-Riedesel/HimemX/blob/master/Readme.txt
OR:
https://gitlab.com/FreeDOS/base/himemx/-/tree/master/DOC/HIMEMX
OR:
C:\FREEDOS\DOC\HIMEMX\readme.txt (can be installed with FD live CD).
Examples:
IN CONFIG.SYS / FDCONFIG.SYS:
files=20
buffers=30
lastdrive=Z
break=off
DOS=high,umb
device=C:\FREEDOS\BIN\himemx.exe
device=C:\FREEDOS\BIN\jemm386.exe NOEMS
shellhigh=C:\FREEDOS\BIN\command.com C:\FREEDOS\BIN /E:1024
/p:C:\fdauto.bat
See also:
config.sys/fdconfig.sys
devload
(fdxms)
(fdxms286)
jemm386
jemmex
xmgr
Copyright © 2011 W. Spiegl, updated in 2022.
This file is derived from the FreeDOS Spec Command HOWTO.
See the file H2Cpying for copying conditions.