• Please review our updated Terms and Rules here

Boot/Install To DDO Equipped Physical Hard Disk through Virtual Machine

creepingnet

Veteran Member
Joined
Feb 25, 2005
Messages
1,103
Location
Reno, NV
Ok, so I have a 486 DX2 with a wonky Floppy controller (almost NONE of the floppy drives, cables, and the like, seem to work right in this machine), and I've got a 40GB Maxtor HDD that is setup with a DDO that I want to use in said 486. I also have a Dell 5100 that I could use but I don't feel like bothering with re-connecting it.

I have 2 Virtual Machine programs I can use, VirtualBOX (Windows/Linux), and Windows Virtual PC (windows live essentials version). Is there any way to map the physical drive to the Virtual Machine so it reads the DDO, allows me to write the data to the drive (as normal), and basically "Image Out" the drive before installing it in the computer.

I'm trying to avoid having to fix the Floppy Issue since every controller, cable, and drive I've put into it has failed to work (though, funny enough, they all work on my 286 just fine). On the 486, no matter which controller/cable/drive I use out of my stash, it fails to work. Drive A:\ (1.44MB 3.5") will see all the files on disk, Drive B:\is not even seen sometimes even if listed in the BIOS (usually the problem with Win95 and Win98), and A:\ will sometimes copy files but the files will be corrupt upon attempting to run an executable on the hard drive, or opening some other file, and sometimes, files won't even read/write but rather give errors.

So that's why I want to try this crazy workaround and wondered if anyone else here had experience with using a VM to build out a HDD, or bypassing DDO's to install an O/S.
 
Well, most DDOs had their overlay software on the first physical track of a drive and the "real" parition table, etc. started on Cylinder 0, head 1... So you could image the important part using dd with a starting offset.
 
Controllers work with the 286 but not with the 486? A thing that comes in my mind is a possible high ISA BUS clock. Usually the BIOS or jumpers, have an option to set the ISA clock as a divider of the BUS clock. The "normal" ISA clock should be about 8 MHz, though most cards are fine with up to 10 MHz. Higher than that though, might cause instability to some. Eg if you have a 40 MHz BUS clock and an 1/3 divider, it will clock the ISA at 13,3 MHz and it is quite high. The 1/3 divider is relatively high for a 33 MHz BUS as well, giving 11,1 MHz ISA clock.
If the controller is a VESA one, you might need to specify jumpers on the controller if you have a higher than 33 MHz BUS. Maybe even add VESA wait states on the mainboard as well.
 
Controllers work with the 286 but not with the 486? A thing that comes in my mind is a possible high ISA BUS clock. Usually the BIOS or jumpers, have an option to set the ISA clock as a divider of the BUS clock. The "normal" ISA clock should be about 8 MHz, though most cards are fine with up to 10 MHz. Higher than that though, might cause instability to some. Eg if you have a 40 MHz BUS clock and an 1/3 divider, it will clock the ISA at 13,3 MHz and it is quite high. The 1/3 divider is relatively high for a 33 MHz BUS as well, giving 11,1 MHz ISA clock.
If the controller is a VESA one, you might need to specify jumpers on the controller if you have a higher than 33 MHz BUS. Maybe even add VESA wait states on the mainboard as well.

Thanks, I'll try looking into that.

As for the other part of this thread, I managed to work around it. I already had the DDO on the drive and found a DOS 7.10 diskette 1 in my stash of Floppies and managed to partition, format, and install DOS and Win95 OSR2 on the 40GB drive. For the past 2 days that thing has been getting fed umpteen Gigabytes of vintage app and gaming goodies. It's quite nice, I have the Doom Collection already running on it without need for a CD-ROM, and am working on getting Diablo and a few others to that point as well. I'm rather shocked how well Doom 95 runs on Windows 95 OSR2, especially with AfterDark 4.0 loaded (Flying Toilets FTW!!!).
 
Back
Top