virtualbox.org

Set up a DOS VM with USB

Overview

This is about DOS 6.22 and USB; tried with VirtualBox 1.4.0 (with 1.3.8 I did not get this far).

My host system is a typical WinXP machine with 1280*1024 display.

The post builds on to my earlier one describing the setup of a DOS VM including CDROM and NIC drivers:
http://forums.virtualbox.org/viewtopic.php?t=845

Results

I got it working with some restrictions; the result depends on the drivers you can find. Be prepared for some rebooting of your guest !

Prequisites

What do you need apart from a DOS VM:
- a driver called usbaspi.sys (USB to ASPI)
- and an ASPI disk manager.
Both need to be loaded in config.sys. Both come in various flavors as well.

A hint for usbaspi.sys: a file (460,246 bytes) kxlcb45an.exe from Panasonic with version 2.20.

Get yourself familiar with the VirtualBox manual on USB.

Loading the drivers

First about usbaspi.sys: my best options are:
- usbaspi.sys 2.20
- usbaspi.sys 1.06
- usbaspi.sys 1.03
All from Panasonic, 2.20 beats the rest.

Next about an ASPI disk manager: my options are:
- ASPIDISK.SYS (Adaptec; Ver. 4.01b)
- nj32disk.sys (ASPI DISK Driver Ver. 1.06 by Workbit Corp.; will not work beyond 512MB ???)
- di1000dd.sys (if you can’t find anything else... )

Statement to add to config.sys may vary somewhat but this should do, as detailed below.
For usbaspi.sys:
- device=c:\usbaspi.sys /w /v /o (the letter O, not the digit zero)
And for the ASPI disk manager (select the appropriate one)
- device=c:\di1000dd.sys
- device=c:\aspidisk.sys /d
- device=c:\nj32disk.sys /r

My experiences

The result depends on the drivers. Some rebooting may be needed to have the VM capture the USB drive.

A useful VirtualBox command is "vboxmanage list usbhost". It can return these states for a USB device:
- busy: host is using it
- captured: guest is using it
- held: intermediate state: host is recapturing after guest shutdown

Performance is usually slow (especially when compared to networking a DOS machine to you host), e.g. 25 s for a 3.5 MB file. Typically speed is limited to USB 1.x anyway.

Sometimes VirtualBox even quits - but always and only after apologizing. Just reminds me of how stable it is otherwise.

I used USB flash drives only; size from 256 M up to 1 G.

Links

Just a few...

- http://www.toolsthatwork.com/bbdocs/usb.htm (ByteBack article; note the remarks about MBR and speed)
- http://www.freedos.org/freedos/news/technote/203.html
- http://www.bootdisk.com/usb.htm
- http://www.usb.org (with the USB standards & more)

Hey ghr!

Thanks for you tutorials! But I really suggest to add them to the wiki. Otherwise them get so deep in the forums no more attention and this would be a pity.

Just one question for my curiosity... For what set up dos in VirtualBox? I have read here in the forums and on a lot other websites that the most compatible way to run legacy dos apps is old hardware... Followed by dosbox.

But VirtualBox? What you can still do with dos? Games are not running? Or are them for you?

Well nabamer... it started off with me wondering if I could do without my old hardware. The result is: now I'm at least less vulnerable There ARE some reasons why I prefer VirtualBox over e.g. DOSBox or Qemu: it is more general purpose and more stable especially when it comes to networking.