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This page needs major cleanup to make it easier to read, shorter, etc. The entry imported from FD-DOC had many edits by Eric, who was very wordy. Jhall1 16:13, 24 December 2008 (UTC)

Note about CDROM installer (FreeDOS 1.2)

What's the difference between the "standard" and "legacy" versions of the FreeDOS 1.2 install CDROM? Jerome Shidel mentioned this in a comment on Facebook, related to installing on Virtualbox, and I am repeating it here:

The CDs use two completely different boot methods. One FD12LGCY uses floppy emulation. The FD12CD informs the system to load a binary image as a boot loader.

The FD12LGCY version uses the original “El Torito” bootable CD specification. Basically, it is limited to booting a floppy image as a BIOS emulated drive. This method should work on ALL hardware that supports CD booting. But, it does not. In my opinion, I think most BIOS manufacturers and Virtual Machine developers don’t do much testing with this ancient version of the specification. For example, FreeDOS will lockup when a program access the data portion of the CD-ROM from any program outside of COMMAND.COM under VirtualBox. Wether that bug is in VirtualBox or on the FreeDOS side is unknown. The FD12CD image uses a much later method of booting. It loads a binary blob (SYSLINUX) as a boot loader. That runs MEMDISK which loads and emulates a floppy disk image. This is a much more complicated process. But, this method is preferred for newer hardware and works fine on VirtualBox. This is probably do to MEMDISK emulating the floppy instead of the BIOS. So, nearly all hardware prior to a Pentium II (I think) will not be able to boot using the more complex binary blob process. This leaves a narrow range of hardware that may have a CD-ROM and will require the FD12LGCY version (probably 386 thru Pentium II).