> On Dec 4, 2016, at 3:31 AM, Philip Hoefer <philscomputer...@gmail.com> wrote:
> [..]
> 4. The error message was invalid opcode, but scrolled very fast and 
> indefinitely. I have seen this before with modern linux distributions when an 
> old CPU is not supported.
> The note on the website is as follows:
> FD12CD.iso <http://www.freedos.org/download/download/FD12CD.iso> (full 
> installer CDROM) —If you have problems with this image, try FD12LGCY.iso 
> <http://www.freedos.org/download/download/FD12LGCY.iso>
> Using FD12LGCY, which I presume stands for legacy, works on a Pentium 200.

FD12LGCY does stand for Legacy. For the most part, both of the ISO images are 
identical. Except for one thing, the CD boot process. The good news is 
regardless of which CD you use. You will get the exact same version of FreeDOS 
and the exact same packages. The bad news, it appears both ISO versions are 
going to be required. 

Here is a little more information on the differences between the ISO versions. 

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). 

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