How to install FreeDos onto a usb stick?

Unfortunately the current information on the FreeDOS Wiki is not up to date, but with the help from FreeDos Developer Jim Hall I could find the solution:

  1. Download the USB “Full” installer from the FreeDOS page.
  2. Unpack the downloaded zip
  3. Use a USB formatting tool (for example rufus) to write the image to USB (take care to write over the right drive)
  4. Move the directory D:\FDSETUP\BIN to D:\BIN
  5. Edit first and last two lines in D:\FDCONFIG.SYS as follows

    !COUNTRY=001,858:\BIN\COUNTRY.SYS
    !LASTDRIVE=Z
    !BUFFERS=20
    !FILES=40
    
    DOS=HIGH
    DOS=UMB
    DOSDATA=UMB
    
    DEVICE=\BIN\HIMEMX.EXE
    
    SHELLHIGH=COMMAND.COM \BIN /E:2048 /P=\AUTOEXEC.BAT
    
  6. Edit D:\AUTOEXEC.BAT as follows (Windows will hide this file, but you can open it by directly giving the filename). Only the line setting the DOSDIR needs to be changed and some display code at the end of AUTOEXEC.BAT are to be removed

    @echo off
    SET DOSDIR=
    SET LANG=
    SET PATH=%dosdir%\BIN
    
    SET DIRCMD=/P /OGN /Y
    
    rem SET TEMP=%dosdir%\TEMP
    rem SET TMP=%TEMP%
    
    rem SET NLSPATH=%dosdir%\NLS
    rem SET HELPPATH=%dosdir%\HELP
    rem SET BLASTER=A220 I5 D1 H5 P330
    rem SET COPYCMD=/-Y
    
    DEVLOAD /H /Q %dosdir%\BIN\UDVD2.SYS /D:FDCD0001
    
    SHSUCDX /QQ /D3
    
    rem SHSUCDHD /QQ /F:FDBOOTCD.ISO
    
    FDAPM APMDOS
    
    rem SHARE
    
    rem NLSFUNC %dosdir%\BIN\COUNTRY.SYS
    rem DISPLAY CON=(EGA),858,2)
    rem MODE CON CP PREP=((858) %dosdir%\CPI\EGA.CPX)
    rem KEYB US,858,%dosdir%\bin\keyboard.sys
    rem CHCP 858
    rem PCNTPK INT=0x60
    rem DHCP
    rem MOUSE
    
    rem DEVLOAD /H /Q %dosdir%\BIN\UIDE.SYS /H /D:FDCD0001 /S5
    
    SHSUCDX /QQ /~ /D:?SHSU-CDR,D /D:?SHSU-CDH,D /D:?FDCD0001,D /D:?FDCD0002,D /D:?FDCD0003,D
    
    rem MEM /C /N
    
    SHSUCDX /D
    
    rem DOSLFN
    
    rem LBACACHE.COM buf 20 flop
    
    SET AUTOFILE=%0
    SET CFGFILE=\FDCONFIG.SYS
    alias reboot=fdapm warmboot
    alias reset=fdisk /reboot
    alias halt=fdapm poweroff
    alias shutdown=fdapm poweroff
    
    rem alias cfg=edit %cfgfile%
    rem alias auto=edit %0
    
    vecho /p Done processing startup files /fCyan FDCONFIG.SYS /a7 and /fCyan AUTOEXEC.BAT /a7/p
    
  7. Delete D:\SETUP.BAT

  8. Done, safe your files and safely remove the USB stick

Boot and test

The USB key now boots directly into FreeDOS and loads into high memory, leaving roughly 600KB of common memory for programs.