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Old PC Floppy images

Ozfer

Experienced Member
Joined
Jan 15, 2014
Messages
82
Location
Connecticut USA
There are so many floppy disk image formats I am losing count. I want to get some really old software to my ibm 5150 and some very old software only comes in certain formats. For example IBM DOS 1.0 or 1.2 only is available online in 160k odd format binary IMG files. These files cannot be mounted like normal floppy disk images, and I cannot write them from a modern computer. Furthermore I currently don't have 160k disks.

Also Flight simulator 1.05 only comes in the same format of IMG file and I cannot mount or burn it and most normal programs I use report it as corrupt. How in the world can I get the files out or just get them on a 720kb floppy in general?
 
I see two problems with trying 160kB disk images. The hardware being used may not support single sided operation correctly. The software may be confused by the disk having the DOS 1.x format which lacks the BPB introduced with DOS 2.

If you have the most common DOS 1 images around, they are hacked out from a DIM file in a crude fashion that almost no program understands. If you can find the DIM originals and the DIM software, DIM will write it out to disk. Or tweak an emulator to use it. If the emulator is directly connected to a floppy drive, it may be able to write a usable DOS 1 disk.

http://thestarman.pcministry.com/tool/hxd/dimtut.htm
 
WinImage can create 160kB images, if it can open them you can change the image format within WinImage and save it as a different size image.
You can then can use the bigger image in an emulator or write to a disk.
 
The problem is that WinImage is not just a disk writer, but also a file extractor. So it always insists on trying to process the file system within the disk image. It only knows about FAT file systems, and it is too stupid to know about DOS 1.x disks which lack or have an incorrect Bios Parameter Block in the boot sector. Many game "booters", such as flight simulator, don't even HAVE a file system!

At any rate, there is not much you can do about it other than use a different disk writer tool.

If you are using a computer with a real Floppy Disk Controller and not a lobotomized USB floppy drive, then the best options are DOS based disk writers.

You can write "raw" 160K/180K/320K/360K disk sector images (.IMG, .IMA) with M Brutman's DSKIMAGE tool:
http://www.brutman.com/PCjr/pcjr_downloads.html

And many archives are in ImageDisk (.IMD) format:
http://www.classiccmp.org/dunfield/img/index.htm

There is a guide to convert raw 160K/180K/320K/360K disk sector images to ImageDisk format here:
https://winworldpc.com/winboards/viewtopic.php?t=6931

If you absolutely need a solution for "modern" lobotomized hardware, then you can feed the above IMA,IMG,and IMD files to the HxC disk tool, save them as a SuperCard Pro or KryoFlux stream and write those using one of those devices.

WinImage can create 160kB images
It says it can, but it actually gets it wrong.

Furthermore I currently don't have 160k disks.
160K is Single Sided Double Density in DOS 1.x 8-sector format. You can write these to any Double Sided Double Density 5.25" (360K) media. You can also tell most disk writers to write them to Double Density 3.5" (720K) media.

Also Flight simulator 1.05 only comes in the same format of IMG file and I cannot mount or burn it and most normal programs I use report it as corrupt. How in the world can I get the files out
Flight Simulator doesn't have files.
For others, unless someone has written a smarter file extractor, the only way is to hex edit the image to add a correct Bios Parameter Block.
 
There is no early dos image in the wild other than IMG ?
I have an original IBM PC DOS 1.1 box and disks.
Time to crank up my 5150 with Mr. Dunfield's ImageDisk !!!

I don't suppose the released source code could be scaled back to 1.0 ?
Is there, or has anyone made a bootable 1.0 ?

More questions than answers and probably answered many times over on this forum ...

Larry G
 
Hi Ozfer,
I meeted the same problem for some pcbooter game I.E. "Lode Runner Championship". See my Facebook page:

https://www.facebook.com/OlivettiProdestPC1/posts/1667582846793464

I have made a Floppy emulator (it works with plain IMG files from 160k to 2.88 M)

https://www.facebook.com/OlivettiProdestPC1/posts/1671151433103272:0

It can Mount a single Floppy image in A: drive (original A: can be found in B:) and also boot directly from it (like dosbox). The only requirement are an Hard Disk (where is the image file) in FAT16, DOS 4+ (to begin with, then it can boot also DOS 2) 80186+ and about 6kb ram.

Contact me in pm if you are interested to the program.
 
If you have an image with a .DIM extension there is a program called 'Disk IMage Archiver' that will handle it. If you need it let me know.

I have a few different images with extractors of DOS 1.0 and 1.1. AFAIK, they all worked when I used them. Some are self-extracting .EXEs. Plus I have a collection of image extractors.
 
Yes I have the DIM version of early DOS and I was able to edit the binary stuff out in a hex editor to make it a perfect img file. I also tried using DIM but DIM insists on only writing to a 360k or 160k floppy and will not write it to a 720k.

Winimage always complains about these formats and will not let me write them. Also my only option at the moment is to either copy files over onto the computers hard drive, or to put the files onto 720Kb floppy disks as I don't have any 5 inch disks with me and my computer doesn't have a 5 inch floppy drive, or a real floppy drive controller ( I am using USB). I really need one of those nice catweasel cards...

It would be great if someone could get a copy for us that is not in this IMG format I would love that.

Stone is Disk IMage Archiver the acronym for DIM? I tried the DIM program and it wouldn't work. If that program is different can it extract files or get it on a 720k? If anyone can send me files that work I would appreciate it.

Thanks for the help guys.
 
As you are familiar with hex editors, you can use them to patch out the 160k image to "convert it" to a 360k or 720k image. At the end of each track in the image (after every 4096 bytes), add 512 bytes of padding if you want to make a 180k image, or rather 5120 bytes of padding if you want to make a 360k image. If you want to extend this to a 720k image just add another 360k of padding to the end of the 360k image.

Note: This might enable you to write them to disk with Winimage, but the resulting disk will still act as a 160k disk when accessed in DOS. The actual physical type of disk doesn't matter as DD 3.5" media use the same bitrate as 5.25" media. Just make sure to use DD floppies without the "HD enable" hole in the corner.
 
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WRT microsoft flight simulator, most of the images I've seen (at least the ones in the total dos collection) are distributed as .td0 files. That's teledisk, which is a DOS disk image making/writing program which can handle the oddly formatted flight sim disks and write them back to an actual floppy disk. These images are not (AFAIK) able to be booted in emulators like dosbox.

You might want to play with MS flight sim v2.1, also available in total dos collection, which was hacked apart by some dedicated nerd to be executed from DOS and not booted to as a disk image. You can simply unzip the game onto any media and play it.
 
Well, I get a lot old disk images, PC-DOS 1.0 included. Here's how I keep the customer happy with PC disks.

I extract any files and archive them, I include an IMD image--and then a raw binary (sector by sector) file with a text description of the format. That seems to keep the archivists happy.
 
It would be great if someone could get a copy for us that is not in this IMG format I would love that.
You can convert raw sector images to ImageDisk using the following commands:
Code:
160k raw to imd: (163,840 bytes)
BIN2IMD <image.img> <image.imd> DM=5 N=40 SS=512 SM=1-8 /1

180k raw to imd: (184,320 bytes)
BIN2IMD <image.img> <image.imd> DM=5 N=40 SS=512 SM=1-9 /1

320k raw to imd: (327,680 bytes)
BIN2IMD <image.img> <image.imd> DM=5 N=40 SS=512 SM=1-8 /2

360k raw to imd: (368,640 bytes)
BIN2IMD <image.img> <image.imd> DM=5 N=40 SS=512 SM=1-9 /2

1.2mb raw to imd: (1,228,800 bytes)
BIN2IMD <image.img> <image.imd> DM=3 N=80 SS=512 SM=1-15 /2

720k (3.5") raw to imd: (737,280 bytes)
BIN2IMD <image.img> <image.imd> DM=5 N=80 SS=512 SM=1-9 /2

1.44mb raw to imd: (1,474,560 bytes)
BIN2IMD <image.img> <image.imd> DM=3 N=80 SS=512 SM=1-18 /2
 
My ancient utility, COPYQM had a CONVERT=<format> option also, but the target was always a physical disk. You had two types of conversion---"smart", where DOS layout was followed and "stupid" where a sector-by-sector copy was done without regard for the OS format.

So, not new at all.
 
Kudos, Chuck, I used Copyqm for about ten years (1990s), mainly for multiple disk duplication. I always thought it was an excellent program -- and that was a long time before I knew you. :)
 
Yeah, it was pretty popular. Could only get a few interested in SyDupe, however--the "supercharged" version of CopyQM--it used up to 3 controllers to simultaneously format, write and verify 3 floppies at the same time. I've still got an old 486 tower here set up with 6 drives that I use to screen old floppies for reuse.
 
Also Flight simulator 1.05 only comes in the same format of IMG file and I cannot mount or burn it and most normal programs I use report it as corrupt. How in the world can I get the files out or just get them on a 720kb floppy in general?

You can't, as Flight Simulator 1.05 doesn't use files or have a filesystem. It's a bootable program, and came that way originally.

You can get it onto a 720K disk if you use a "raw" image writing utility; just specify single-sided and force it to write until it runs out of data. It will still work and boot, since 720K disks are just 360K disks with double the number of tracks.

There is no early dos image in the wild other than IMG ?

"IMG" usually means "raw dump of a disk, side 0 first, then side 1, from track 0 to the last track". This is very common and most "raw" or "image" programs support it (rawwrite, winimage, etc.).

"IMD" was the extension chosen by Dave Dunfield for IMageDisk. The file format is not raw as it contains much metadata about the disk's format and structure. ImageDisk can write such images back to floppy, and the file format is open and fully described so archivists will always be able to get at the contents. If an IMD image contains a regular floppy with nothing special or out of the ordinary, it can be converted to a raw image using a utility bundled with ImageDisk.

Occasionally you will see "TD0" for Teledisk images, created by our own Chuck Guzis in the 1990s. These were used by early archivists before ImageDisk existed, as Teledisk images can properly preserve and reconstruct some protected disk images. I believe the PCem emulator, or PCE emulator (or both) can mount and read them. You can always write them back to a floppy disk once you transfer the software and images onto a vintage system.
 
Also, ".DSK", often used with raw sector-by-sector dumps to be used with RAWREAD and RAWWRITE--and UNIX "dd". Those, and a text file describing the layout is probably the most transportable form. So, even if you can't run the utility that deals with them, you can write your own version.
 
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