Installing Freedos 1.4 on Ubuntu 24.04

About a week ago, I came across this Hackaday post about a UEFI-wrapper project that re-enables legacy BIOS on UEFI-only systems. Coincidentally, FreeDOS v1.4 was just released, so I decided to repurpose an old laptop as a pure FreeDOS machine. Because DOS requires a BIOS runtime (no native UEFI support), most modern machines can’t run it natively.

I tried CSMwrap on my janky laptop, but things didn’t quite work. Since I mainly wanted to try FreeDOS rather than dive into a UEFI rabbit hole, I opted to run FreeDOS inside QEMU on Ubuntu 24.04 LTS. Below are the exact steps—including FAT16 partitioning, QEMU command-line options, and networking tweaks… Mainly, so I won’t forget what I did.

Why FAT16?
Classic DOS uses FAT16 (max partition ~2 GB), so we’ll create a 1.5 GB disk to stay well within limits.

All commands assume you’re in $HOME on Ubuntu 24.04 with sudo rights.

1. Download the FreeDOS ISOs

Grab both the Live CD and the Bonus CD:

wget https://www.ibiblio.org/pub/micro/pc-stuff/freedos/files/distributions/1.4/FD14-LiveCD.zip
wget https://www.ibiblio.org/pub/micro/pc-stuff/freedos/files/distributions/1.4/FD14-BonusCD.zip

Unzip them:

unzip FD14-LiveCD.zip
unzip FD14-BonusCD.zip

You should now have:

• FD14LIVE.iso (Live-CD installer)
• FD14BONUS.iso (extra utilities)

2. Install and Verify QEMU

sudo apt update
sudo apt install -y qemu-system-x86 qemu-utils

Confirm the version (e.g. 8.2.2):

qemu-system-x86_64 --version

3. Create a FAT16 Disk Image

qemu-img create -f raw ~/freedos16.img 1536M

• -f raw : raw disk image
• 1536M : 1.5 GB (well under FAT16’s 2 GB limit)

4. Boot the Live-CD and Partition

qemu-system-x86_64 \
  -enable-kvm \
  -m 512 \
  -drive file=~/freedos16.img,if=ide,format=raw,media=disk \
  -cdrom ~/FD14LIVE.iso \
  -boot order=d,once=d \
  -vga std

Where:

• -enable-kvm : uses hardware acceleration
• -m 512 : virtual machine (VM) gets 512 MB RAM
• if=ide : DOS-friendly IDE bus
• -boot order=d,once=d : boot from CD this time only
• -vga std : standard VGA card emulation

When the VM starts, choose Live environment and at the DOS prompt run:

fdisk

1. Press 1 – Create DOS partition
2. Press 1 – Primary DOS
3. Accept default size (full 1.5 GB)
4. Press Y – Write partition table
5. Press 4 – (Optional) List partitions

Reboot:

reboot

5. Install to Hard Disk

When it boots back into the Live-CD, choose Install to hard disk and walk through the FreeDOS installer (language, keyboard, target drive C:). Accept defaults or adjust as needed.

Once done, exit QEMU (Ctrl + Alt + Q) and proceed.

6. Create a Startup Script

Make a start_freedos.sh launcher so you don’t have to type the long QEMU command every time. I like nano as a simple to use text editor:

nano start_freedos.sh

Copy the following contents to the start_freedos.sh file:

#!/bin/bash
# ------------------------------------------------
# start_freedos.sh: launch FreeDOS VM in QEMU
# Usage: ./start_freedos.sh [-cdrom /path/to/iso]
# ------------------------------------------------

# Default CD-ROM ISO
CDROM="$HOME/FD14LIVE.iso"

# Parse -cdrom option
while [[ $# -gt 0 ]]; do
  case "$1" in
    -cdrom) CDROM="$2"; shift 2 ;;
    *)      break ;;
  esac
done

# Build QEMU command
QEMU_CMD=( qemu-system-x86_64
  -enable-kvm
  -m 512
  -drive file="$HOME/freedos16.img",if=ide,format=raw,media=disk
  -vga std
  -device sb16             # Sound Blaster 16 emulation
  -device adlib            # OPL-II FM synth emulation
  -usb                     # Enable the USB driver stack
  -device usb-tablet       # present an absolute‐position USB tablet to DOS
  -net nic,model=ne2k_isa
  -net user
  -display gtk
  -full-screen
)

# Pin to CPU core 3 for stability
exec taskset -c 3 "${QEMU_CMD[@]}"

This script:

• Pins the VM to CPU 3 (taskset)
• Adds Sound Blaster and AdLib support for DOS audio
• Enables NE2000 networking so you can use FreeDOS NET tools
• Makes sure the mouse works without being laggy.
• Launches in a fullscreen GTK window

Dont forget to make the script executable:

chmod +x ~/start_freedos.sh

7. QEMU Key Shortcuts

• Ctrl + Alt + F : toggle fullscreen
• Ctrl + Alt + Q : quit QEMU

8. Adding Games or Extra Files

The simplest way is to build an ISO from your game folder and mount it as D:.

# Install ISO builder
sudo apt install -y genisoimage

# Create game.iso from a directory
genisoimage -o ~/game.iso -J -r ~/PremierManager2/

Then launch:

~/start_freedos.sh -cdrom ~/game.iso

Here I am playing Premier Manager 2!

9. Using the Internet in FreeDOS

With NE2000 networking emulated, you can use the C:\NET tools. For example, there’s a Gopher client:

C:
CD \NET
GOPHERUS