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DR-DOS 7.03 "144" files problem...

Posted: 19. Feb 2011, 09:05
by themikeaustin
All,

I want to try DR-DOS 7.03, because I've heard that it can have more free space below 640K than other DOSes. (I already have/tried PC-DOS 7.1 and FreeDOS. They don't free up enough RAM.) I went to the web site and downloaded 5 disk image(?) files. They have extensions "144". I tried mounting these files in VBox prior to running the OS for installation. I get the following error:

"Failed to open the floppy image <path_name>. Could not get the storage format medium <path_name>.'
(VERR_NOT_SUPPORTED)

Here are the details:

Result Code: VBOX_E_IPRT_ERROR (0x80BB0005)
Component: Medium
Interface: IMedium {9edda847-1279-4b0a-9af7-9d66251ccc18}
Callee: IVirtualBox {d2de270c-1d4b-4c9e-843f-bbb9b47269ff}

I have tried reading this file with WinImage and creating both *.IMA and *.vfd files, but I get the same errors. (WinImage has no problems reading the "144" files.)

As you might have guessed, I don't have a floppy drive on my laptop.

Are they other ways to create image files? Any other suggestions for getting this to install? What's the best DOS for maximizing RAM below 640K?

TIA,

Mike

Re: DR-DOS 7.03 "144" files problem...

Posted: 20. Feb 2011, 18:58
by FrodoHobbits
Create the set of disks using an existing DOS guest.
Using WinImage to create 5 blank disks, copy all the 144 files and makedisk files to the DOS C: drive.
Run makedisk and insert disks 1 to 5 when instructed, you will then have a set of DR-DOS installation floppies.

Re: DR-DOS 7.03 "144" files problem...

Posted: 20. Feb 2011, 23:24
by themikeaustin
Thanks for taking the time to reply. Unfortunately, the whole point of my post is that a) VirtualBox can't read the Winimage-created files and b) I can't use floppy disks because I don't have a floppy on my laptop.

Mike

Re: DR-DOS 7.03 "144" files problem...

Posted: 21. Feb 2011, 09:55
by FrodoHobbits
You don't need a floppy drive.
WinImage will create disk images without you having an actual floppy drive.
Create a new image and save it out to a directory (uncompressed), rename the extension from .ima to .img, VBox will now recognise this image.
Repeat for as many blank disks as you require.

Re: DR-DOS 7.03 "144" files problem...

Posted: 21. Feb 2011, 22:58
by themikeaustin
Thanks for your response. My problem is that WinImage works perfectly, but VBox can not read the image file. If you read my original post, you'll see that the error messages are from VBox, not WinImage, and the error implies that the version of the image files is not supported by VBox. If this is the case, then I need to use some other tool to create the image file(s). Do you have any suggestions?

TIA,

Mike

Re: DR-DOS 7.03 "144" files problem...

Posted: 22. Feb 2011, 09:51
by FrodoHobbits
Hi Mike,
The .144 files are encripted/compressed (dont ask me), I get the same message in VBox to if I try and mount them. Using WinImage as I suspect you did to read the .144 disks and create new .ima/.img files still will not work, you get the same message.
You need to download the mkdskzip.exe file from your source, this file when copied to a DOS guest along with the 5 .144 files will create the 5 floppies needed but you will need 5 blank floppy images to proceed, these you leave on your host pc and are easy to create using WinImage.
You will need to run mkdskzip.exe to extract makedisk.exe, run makedisk.exe and follow the simple instructions.
It took me around an hour the other day to create a DR-DOS guest, this included sourcing the files, creating a DOS-6.2 guest used to create the floppies needed.
Hope this has helped.

Re: DR-DOS 7.03 "144" files problem...

Posted: 13. Mar 2011, 21:12
by bttr
It could help to extract the first 1,474,560 bytes from every .144 file to get working images. (i.e., cut the "DiskImage 2.01 (C) 1990,1991 Digital Research Inc." signature.)

With http://www.bttr-software.de/x/ (for DOS or Win32) you say:

Code: Select all

x disk01.144 disk01.img 0 1474560
...

Or in a loop:

Code: Select all

for %i in (1 2 3 4 5) do x disk0%i.144 disk0%i.img 0 1474560

Re: DR-DOS 7.03 "144" files problem...

Posted: 21. Mar 2011, 15:42
by mpack
themikeaustin wrote:I want to try DR-DOS 7.03, because I've heard that it can have more free space below 640K than other DOSes. (I already have/tried PC-DOS 7.1 and FreeDOS. They don't free up enough RAM.).
Simple curiosity here, since you already seem to have been given good advice...

I'm curious as to what application this is? It is strange to me that a DOS era developer would create an app that requires so much memory that it only runs on one obscure DOS clone (i.e. doesn't even run on the genuine MS article).

Re: DR-DOS 7.03 "144" files problem...

Posted: 21. Mar 2011, 18:12
by themikeaustin
The game is called Harpoon. It's similar to Fleet Command, which is a Windows game. It is a war-gaming application, that consists of scenarios that you have to work through. Most of the scenarios fit into RAM, but a couple of the better ones do not.

Re: DR-DOS 7.03 "144" files problem...

Posted: 5. May 2016, 07:46
by jleg094
bttr is correct, the issue is that VirtualBox only accepts floppy images 1474560 bytes long. The dr-dos disks have a footer, causing them to exceed that size. A simple dd will extract the first 1474560 bytes of the disk and save it to another file.

Code: Select all

$ dd if=disk01.144 of=disk01.img bs=512 count=2880
Worked like a charm for me!

Re: DR-DOS 7.03 "144" files problem...

Posted: 5. May 2016, 09:27
by mpack
jleg094 wrote:bttr is correct, the issue is that VirtualBox only accepts floppy images 1474560 bytes long.
Good advice, though the quoted bit is not quite correct. VirtualBox is not just working like an archiver, it's emulating a specific floppy drive, and it's the floppy drive that expects media in a particular size and format. Several 3.5" sizes are accepted (i.e. single and double sided), also you can also configure the VM for a 5.25" floppy drive, and then several other sizes are accepted by that drive. This is just additional information, your main point is valid and very useful.

Re: DR-DOS 7.03 "144" files problem...

Posted: 5. May 2016, 10:45
by ghr
mpack and others, some more useful info: using 4.3.36 with Ubuntu host I discover that VB can handle read-only images, great !!!!!!!! Just that I have good memories about those write-protect tabs...

Re: DR-DOS 7.03 "144" files problem...

Posted: 8. May 2016, 20:34
by ZenHacker
I'm having the exact same problem. Like you, I attempted to install DR-DOS on a Virtual Machine by downloading the .144 files from an abandonware site (though I'm using a Mac OS X host). I Googled the .144 extension, and all I can find is information on a file format used by a German mathematics program to generate Julia set fractals. I can't seem to find any information on .144 floppy images. This seems to be a very obscure file format. Suggestions, anyone?

Re: DR-DOS 7.03 "144" files problem...

Posted: 8. May 2016, 20:52
by socratis
Try renaming it to one of the following extensions that are accepted by VirtualBox for floppy images:
  • img
  • ima
  • dsk
  • flp
  • vfd
Any file could have any extension. That doesn't mean that it actually follows the extensions convention. You could name it .jpeg; that doesn't make it a picture.

Re: DR-DOS 7.03 "144" files problem...

Posted: 8. May 2016, 20:57
by ZenHacker
I think .144 refers to the 1.44 MB capacity of a floppy disk, so I think it is a valid format. The trouble comes when you have a file that VirtualBox thinks is in one format (say .IMA) because that's what it's extension indicates, but it's actually in the .144 format, which could lead to erratic behavior.