[Ham-Computers] RE: Flash drives, DOS, etc

[Hsu, Aaron (NBC Universal)]

>>> KO6BB wrote: 

I DO still have my old DOS 6 disk set.  I wonder if it's possible to use a flash drive as a virtual machine UNDER Win-XP and set it up with DOS 6, while still running other apps in WinXP. To be honest, this doesn't sound do-able to me as it seems like you'd be running two OS's at the same time, but then I'm no expert either.  If not then I'll just set the program up on the Win95 machine and forget it (though it'd mean running two computers simultaneously on an already cluttered listening bench).

>>> My reply:

Sure it's possible...that' what virtual machines (VM's) are!  VM's allow you to run a a "virtual computer" inside of a "host" operating system.  With Microsoft's Virtual PC 2004, Windows 2K/XP is your "host" and the VM run whatever other Microsoft OS (the "guest) you wish to run.  In fact, you can run several guest VM's at once (if your system has enough RAM and horsepower).  VMWare works the same way, but there are flavors that allow the host to be a Windows based OS or Linux based (the highest end VMWare "ESX" server is Linux based).  For flexibility, VMWare is much better, but Virtual PC is easier to use.

So, Phil, what you would do to get that old app running is to create a VM "guest (let's stick with VPC for now), assign it 64 or 128MB RAM, create a dynamic virtual drive, and then "boot" from your DOS 6 floppy (you'll "capture" the floppy drive so the VM can use it).  All of this is done while you're in WinXP.  Once DOS 6 finishes booting, you'll be at the DOS prompt in the VM session.  BTW, the VM session runs as a window, so you can still work on other things while the VM is running.  In the DOS 6 VM, do an FDISK and FORMAT of the virtual HD and you're all set.  You can now remove the floppy, "reset" the VM, and it will boot to DOS 6.

Basically, you're doing everything the same way you would have done on a different computer.  The only difference is that you're doing it in a VM session - a window while in WinXP.  If you want, you can <Right-ALT><Enter> and the VM session will now be full-screen (repeat to go back to a window).  With Virtual PC, once you're done installing the "guest" OS, you run the "VM Additions" to add specific Virtual PC support to the VM session (such as drag-n-drop to the "host" OS, VM specific video drivers, network share support, etc).  A similar option is available in VMWare.

And, since Microsoft's Virtual PC 2004 is free, you've really got nothing to lose by trying.  Everything in a VM session is self contained - it's near impossible to "blow up" anything in your "host" OS unless you decide to use a physical HD as the virtual HD (not recommended).  BTW, the virtual HD is a file created on your "host" system.  It just shows up as a file.  By default, VPC uses dynamically sizing virtual HD's, so the filesize will change, but it will never be larger than the "max" size you specified when you created the virtual HD.

There's no guarantee that the app will work, but many of the "pesky" DOS apps I have that refuse to run in Win2K/XP work fine in a virtual DOS session under VPC.  This includes a graphics viewer (SEA) that uses VESA graphics modes.  I've yet to try some old games, but I'm pretty sure they'll work too.

If you have any questions about setting up the VM, post a message or e-mail me.  Someone in the group will have answers.


73,

  - Aaron Hsu, NN6O (ex-KD6DAE)
    {nn6o}@arrl.net
    {aaron.hsu}@nbcuni.com
    No-QRO Int'l #1,000,006
    . -..- - .-. .-   ".... . .- ...- -.--"