msdos 4.01

[jabost1]

i am using vb 4.1.2 on a win vista system (p4 3gz 2gram 320g hard drive) and am trying to install msdos 4.01. the install process completes successfully, but then booting of the vm hard drive gets a lockup after the bios vb splash screen. can any body help with the solution to this problem? ive tried the options on the system tab, and the vm storage tab (including a vm scsi drive). there is no problem with the select install on the msdos setup disks. thanks in advance.

[michaln]

The problem is the BIOS in VirtualBox. DOS 4.x (both IBM and Microsoft versions) is unusual in that it calls the fixed disk BIOS (INT 13h) early in the boot stage with a very small stack, approximately 100 bytes IIRC. The VirtualBox BIOS needs slightly more and crashes/hangs because the stack overflows. This happens only when booting from hard disk, there is no problem accessing the disk when booting from floppy. This is also specific to DOS 4.x, it does not happen with either earlier or older versions of DOS.

The easiest workaround for you is to create a boot floppy (image) and use that, pointing the PATH etc. to C:.

This will probably be fixed in VirtualBox at some point, but that does not have a particularly high priority.

[michaln]

BTW if you're really really interested, I can give you an alternative BIOS image that should fix the hang and allow booting of DOS 4.x from disk.

[jabost1]

if you can post that bios image here, i would appreicate it. im also sure that some other people wpuld also like that help also. thanks.

[michaln]

OK, the alternative BIOS is attached. Please keep in mind that it has not been extensively tested. However, if you run into problems with it, let me know.

To use it in a VM, extract the .rom file from the archive and place it in a directory where the VM can access it. Then run

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VBoxManage setextradata <vmname> VBoxInternal/Devices/pcbios/0/Config/BiosRom <ROM image pathname>

Note that the alternative BIOS looks almost the same as the standard version and may not be immediately identifiable. But it should be able to boot DOS 4.x

[jabost1]

thanks, it finally worked.

[michaln]

Good to hear. Out of curiosity, why DOS 4.01 (the Windows Vista of DOS), and which release is it? I've been looking for MS-DOS 4.01 from before 1989...

[rauli]

I have a pair of original 720 Kb disks with "MS-DOS 4.01" in the disk labels from a German OEM (but this DOS is in English, not German) but both 4.00 and 4.01 identifies as 4.00, so I have never been sure what version it is.

In the disk labels it is written "MS-DOS 4.01" and "Rel.:01.07.1990" (I suppose it is European date format, so it should be 1st of July, not 7th of January).

If you need more information write me.

[michaln]

There never was MS-DOS 4.00, only 4.01. IBM released version 4.00 (called IBM DOS, not Personal Computer DOS like the previous versions) in 1988 and then quietly refreshed the release without any announcements or version number changes. The original release was from June 17, the refresh from August 3, 1988. I'm not sure when the earliest non-OEM MS-DOS 4.01 release was from, and I'm not sure if IBM ever released something that reported itself as DOS 4.01.

[yuhong]

I think MS-DOS 4.00 did exist but like the PC-DOS version it was pulled within 3 months or so and replaced by 4.01. And AFAIK MS-DOS 4.01 was released toward the end of 1988 and of course took a while to become common.

[michaln]

There was no MS-DOS 4.00 -- that is to say, nothing was ever released. If you have files that show otherwise, I'd love to see them...

[Mousy]

OK, the alternative BIOS is attached. Please keep in mind that it has not been extensively tested. However, if you run into problems with it, let me know.

To use it in a VM, extract the .rom file from the archive and place it in a directory where the VM can access it. Then run

Code: Select all

VBoxManage setextradata <vmname> VBoxInternal/Devices/pcbios/0/Config/BiosRom <ROM image pathname>

Note that the alternative BIOS looks almost the same as the standard version and may not be immediately identifiable. But it should be able to boot DOS 4.x

Please excuse my ignorance but I have a few questions.
What should be used for <vmname>?
What should be used for <ROM image pathname>? ( I copied the rom into the VB directory)
and third,
How do I run the command? (from the Windows Start-run?)

I wonder if this is the same reason v2.11 won't allow me to format the HD?
thanks again

[michaln]

Oh dear. For a reference on VBoxManage, see the manual: https://www.virtualbox.org/manual/ch08.html . If you can't run command line tools, avoid DOS like the plague.

FYI, this isn't "upgrading" the BIOS in the VM so much as replacing it with a different implementation (which you should use only for DOS 4.x).

I have no idea what you mean by "v2.11 won't allow me to format the HD", so I can't answer that.

[Mousy]

Oh dear. For a reference on VBoxManage, see the manual: https://www.virtualbox.org/manual/ch08.html . If you can't run command line tools, avoid DOS like the plague.

FYI, this isn't "upgrading" the BIOS in the VM so much as replacing it with a different implementation (which you should use only for DOS 4.x).

I have no idea what you mean by "v2.11 won't allow me to format the HD", so I can't answer that.

I am very familiar with DOS commands, I grew up with DOS. I am actually nicely surprized I still remember a lot of them, even after 20+ years of not really using DOS
I am not all that familiar with VM as I just started using it a few weeks ago and am still learning it's ins and outs.
BTW: MS-DOS 4.01 boots fine with the floppy, just will not boot on the harddrive.
FYI: Also I just wanted to get back into old DOS and Windows for games and the like.

In MS-DOS version 2.11 when I try to format the Hard Drive, it gives me a fatal error message about not being able to format, bad partition. etc. FDISK seems to work ok tho.

thanks for the info

[michaln]

Yes, DOS 4.x only has trouble booting from (virtual) hard disk. It has no problem using that same hard disk when booted from floppy. It's because the BIOS disk read service uses more stack space than the BIOS floppy read service.

There was no single MS-DOS 2.11, back then it was all OEM versions. And utilities like FDISK or FORMAT would have been written by the OEM. So without looking at whatever particular version you're using, I couldn't tell you what the problem might be.

I have successfully installed PC DOS 2.0 and 2.1 in VirtualBox, so that at least is possible. MS-DOS 2.x versions should in principle work too, but again it depends on what exactly the OEM did.