FreeDOS Flash Drive

From Gentoo Linux Wiki

Almost every BIOS/firmware update needs DOS to work, this article aims to explain how to create a USB flash drive, used to boot on FreeDOS and run those medieval programs. (You will need to have a motherboard BIOS capable of booting from a USB device. Some may also need to enable this option from within their motherboard's BIOS setup screen as well.)

[edit] Requirements

There are several packages you'll need for this, sys-boot/syslinux, which provides various bootloaders (Syslinux, PXELinux, etc.), sys-boot/grub, The GNU GRUB 2 boot loader, sys-apps/util-linux which provides cfdisk(sys-apps/util-linux is part of @system, so you already have this) and last, sys-fs/dosfstools which provides the DOS filesystem tools(mkfs.vfat etc.).

Emerge these packages before continuing:

[edit] Setup

[edit] Partitioning

First thing you need to do is create a partition, let's assume the USB flash drive is /dev/sdb:

Remove everything, create a primary partition, set its type to 0E(W95 FAT16 (LBA)), mark it bootable, write the partition table and quit.

[edit] Formating

Now you can format the partition in FAT16, you can try FAT32 but FAT16 is recommended :

[edit] FreeDOS

There is a nice image of FreeDOS with all you need, you just have to copy a file from it to the partition:

[edit] MBR

Next thing you need to do is make the USB flash drive boot on something, that would be GRUB. You will also need a file from Syslinux to boot FreeDOS.

A nice configuration for GRUB :

default=0
timeout=10
root=(hd0,0)
title FreeDOS
        kernel /memdisk
        initrd /odin1440.img

And finally, you can install GRUB :

[edit] Last touch

Now you can copy your BIOS update/whatever to the USB flash drive (/mnt/usb).

Last step:

That's it, you can boot on your USB flash drive. Once you are in FreeDOS, your flash drive will be c:\, enjoy...

[edit] External links

Old howto upon which this one is based