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The need for DOS

There are still an awful lot of well written computer programs that need DOS to run in. If you have XP or Linux (or BeOS or OS2 or OSX) you can run quite a few of them running the excellent dosbox utility program, but there are still some that want a real dos environment.

I prefer not to play around with partitioning hard disks and setting bootable partitions (except on a new computer with nothing on it just yet) - you can do a lot of damage with those things.

There is a flavour of FreeDOS which comes charging over the hill to the rescue- you can boot from one floppy, and everything you need is there, no need to partition your hard disk at all.
As with ALL flavours of DOS if you do wish to use your hard disk, this one needs a FAT file system to write to - but if you have an NTFS XP hard drive, you may be able to avoid creating a FAT partition by running dos programs from cd, dvd or floppy. If you do this with a floppy disk, FreeDOS will be more stable if you copy the files cmd80x86.com and command.com from the FreeDOS floppy onto the program floppy as these files contain transient dos elements.

If you have a bit of hard disk set up to use a FAT file system, you can use that to install dos programs or to make data available to dos programs. My hard disks use several file systems (fat16, fat32, reisser 3, ext 2) to take advantage of each ones best features for various OS I use.

FreeDOS is free, and very useable.

NOTE that FreeDOS can support Soundblaster cards (dos drivers MAY be required!) or equivalent but does not support the more modern sound chips (so you may have no sound, whereas DosBox running in Linux or Windows will emulate a soundblaster).

I downloaded a 1.44M image file of Odin FreeDOS which is now a little long in the tooth (2004)- the image is copied in Linux using a simple cat command, read the docs. More recently (2007) and more powerfully, it has a replacement Balder (as in Balder, second son of Odin...) which also fits onto a single floppy. Copy on archive.org of Balder http page as original seems to have gone adrift.

Balder requires NO hard disk install, therefore requires no hard disk partition or other dangerous activity. Everything is on the floppy you boot from.

Freedos is also available as an iso for CD in a 39MB installable version - no live version just now. Note- now version 1.1. Note that installing Freedos may overwrite other operating systems or data on your computer. A live CD iso of version 1.0 is available at Freedos 1.0 live CD from Ibiblio- [ Mirror at gwdg.de ] download the 153MB iso. [ Another Live CD mirror at freebsd.org ] Remember to download the file fdfullcd.iso and burn that AS AN ISO NOT A FILE to a CD-R.

If you have chosen the newer Balder, the img file for Balder you have downloaded from the link above needs to be placed onto a real (formatted) floppy as a bootable image-
in Linux the command is:
dd    if=/fullpathto/wheretheimagefileis/balder10.img     of=/dev/fd0

where fd0 is the device name in my system for my floppy drive, which for the purpose of this command should be unmounted (a Linux thing). It will be fd0 for the first floppy drive in almost all Linux systems.

For Windows users, they would use rawrite.exe to move the image to a formatted floppy disk, which then becomes bootable- rawrite is another freely available download You may be able to locate a version of dd for Windows, which uses differing syntax to the Linux version (there used to be one out there...)

You need to boot from the floppy by setting either BIOS or bootloader settings as appropriate. I prefer to have a bootmenu option to boot from floppy, and then leave the bios boot from floppy disabled.

You may need to amend the config.sys (and fdconfig.sys) and autoexec.bat on the floppy for your system but it will probably do something out of the box as it were!

To use my UK keyboard and enable DOS to use UK formats I made the following changes to the default files:
At the end of fdconfig.sys I just added the line:
!country=044,,country.sys
Note the leading exclamation mark which is required.

At the bottom of autoexec.bat on the floppy, I made one small addition- just underneath the line :mouse
LH     keyb     /V     /NOHI      uk,,keyboard.sys
(the NOHI is required as otherwise FreeDos will fall over!)

and as I was going to use one of my fat partitions for dos programs including extensions to FreeDOS I amended the SET PATH entry in autoexec.bat to point to the appropriate part of my hard disk, using the appropriate drive letter as set by FreeDos.

Freedos has a utility to slow down your CPU properly, without amending your Bios, and avoiding the overheating that other utilities can cause which only reduce the CPU time used by your dos program without actually reducing CPU usage. The utility - in both Odin and Balder - is called fdapm.com and it uses ACPI which has been around for some years now (released 1996, common since 1999), but older PCs may not have it. ACPI is a configuration/power management hardware/bios facility.

Just add a line in your autoexec.bat to read for example:
fdapm speed2
one space between fdapm and speed2, and speed2 all one word.

On my system, this generates an error message BUT the system is clever enough to use an alternative system call which does what we want- this is reported on screen and confirmation given that the CPU is available for 2/8 of the time. Note that any reboot will restore the CPU to normal speed.
It is recommended you first use a speed9 setting to safely test if your system supports ACPI functions. The SPEED9 setting returns system data.

We have also used the freedos fdapm with PC Dos 7.1.

One of my dos additions is the excellent dir alternative DI. As this needs to be loaded above the base 64k of ram, I needed to use loadfix, introduced in dos 5. To make life a lot easier, I just added an alias into my autoexec.bat:
ALIAS   DI=LOADFIX   J:\DI
where of course the program di is in the root of my drive J (as lettered by FreeDos). At anytime using FreeDos I just type DI and it works- it does not even have to be in the path as we have given its full path.

I have used various CD drivers and now use a couple- one requires EMS but is huge, one does not use EMS but is small- the standard CD one from Balder which even allows dos to read a data dvd - something dos was not really designed for. My default DOS set up does not use EMS.
Memory usage is DOS is quite dynamic and finding the best set up for the drivers and programmes you wish to use can be rather experimental, especially when there can be a selection of drivers available. For most purposes the default Balder set up should be perfectly adequate.

Opening a hard disk directory of modern proportions can take a while as it works out the free space, but if you can keep your dos programs and data on smaller partitions (say below a gig or two!) things will progress faster
Most dos commands are included, and even a choice of edlin or edit. A mouse driver is included.
No Basic is included and Windows 3 will not install over FreeDOS without problems, but both XP and Linux (via Wine) can run most W3 programs.

Once the system is loaded you have access to all your fat16 and fat32 drive partitions, but no long filenames. As with all flavours of dos, using a file which has a long filename will disassociate the file from its long file name.