Have you tried to read those disks with a program like VgaCopy?

Please try to read the disks with + without the sticker.

Thank you for the advice, I will try that.

So far I have tried "dskimage" and "disk2img". None of them would read the floppy.

KryoFlux should read that disk...
but I don't know if Gotek supports non-standard formats.

If it's a booter, then programs can be more liberal with disk sectoring. Also you might not be able to read them under MS DOS eventhough they're valid. You can capture disk contents in Kryoflux/Greaseweazle and look at it in HXC tools.

I never used a Gotek before, but if Gotek is limited only to straight .IMG dumps then it won't support non-standard formats or other copy-protection schemes, many of which intentionally change sector count on certain tracks only.

havli wrote on 2023-04-13, 08:07:

The whole machine was manufactured by Telequarz in Germany. It was delivered here in 1988-1989 and has been operational since then.
There are two 3.5'' floppy drives, both are bootable. As far as I know they are standard drives you can find in any PC. They were replaced several times in the past 30 years.

German? Weird, that format is more common on Japanese computers, is this perhaps a clone or licenced copy of some JP machine?
77 tracks and 16 sectors is a HD format though, not sure why the floppies have the HD hole covered. I would expect the opposite, DD floppies with drilled holes (I've seen those, have one too).

Anyway, your first issue is most likely that these drives rotate at 360rpm, not 300 as most 3.5" ones do - this format came from 5.25" floppies after all. It is possible the HD sensor was re-wired and these drives can switch the speed depending on the presence of the hole - insert a standard 3.5" HD floppy and listen to the spindle motor. It is possible to tell the difference between 300 and 360 by ear. That being said, this being a German machine, it might be the standard 300 rpm after all.

Second issue is PC DOS is unable to read those (might sort-of work but show garbage with DIR, and will damage the files trying to write to them). A USB floppy in Windows XP or higher should work though, not sure about 98 or earlier ones. Decent USB floppy drives can do both speeds and will auto-detect the format based on bitrate during read, but will be confused by the HD hole being covered.

Lastly the format in question is often 8 sectors of 1024 bytes, not 16 sectors of 512 bytes like what is reported in your program. So it migh be an adaptation of the JP format and in that case, if the first sector does not have a valid BPB, might be unreadable except with manual settings in some floppy image processing programs.

UPDATE: Thinking about it some more, it's probably a standard 300 rpm drive if it uses 16 sectors per track. It would be difficult to fit them at 360 rpm and 500 kbps, it works with 8*1024 bytes because less space is wasted on headers and gaps.

Is this thing from former East Germany, by any chance? If so, the eastern-style drive technology would make sense.

I'm wondering, because it uses language that I would expect from GDR. Because, it's too German.
"vollgrafik" is written with a "k", which fits for eastern German, for example.

Back then, West Germany still widely used the old spelling, so it would read -> "vollgraphik".

Similar word differences : Telefon vs Telephon, Elefant vs Elephant, Delfin vs Delphin, Telegraf vs Telegraph

Also, the term "laden" (it reads "DOS laden"..
In Western German, it would rater say "DOS starten" or "DOS booten".

All in all, the language reminds me a bit of the DCP operating system.
Anyway, it's just a wild guess. Perhaps it's really from West Germany.

Edit: If it's possible to run a DOS program on this machine without the need to modify the original floppies (use a copy instead) :
The program Disc Copy Fast can duplicate floppies, but also can write into an image file.

So it might be possible to dump the control software into a floppy image.
Provided that the floppy image can be stored on something that's accessible later on.

https://m.youtube.com/watch?v=0zEVBO84afk

Hm. Is a serial port available on the device by any chance?
If so, DCF could write the image to a remote drive on another PC.
Needed would be a null-modem and a DOS driver.
Re: 386 , what can I do with it?

Edit: If a floppy image file (use compressed image?) can fit on one of the diskettes..
It's possible to dump the boot diskette in A: to a floppy image located on a floppy in drive B:.
After the file is created, it could be sent via serial port of parallel port (LapLink).

For serial connection, a DOS terminal program could be used for sending the image file.
Or a simple KERMIT program could be typed in via debug program.

Or, the COPY command could be tried. Something like: COPY /B DSK.IMG > AUX
On the reception side, same in reverse. Ctrl-C for abortion.
Assuming that this OS is DOS compatible.
Or, use DDLink: Re: DDLINK: Easily move files between/To/From DOS systems

Edit: The default Gotek firmware is unreliable, in my opinion.
Flash Floppy is a free alternative, with support for non-standard floppy images.

Edit: MS-DOS and PC-DOS before 1987 didn't support 1,44 MB format.
It was introduced in PC-DOS 3.30, I vaguely remember.

Also, PC/XT technology didn't support 1,44 MB format yet, due to the slow floppy controller.
Normally, XTs used a 250KB/s floppy controller, unless updated.
PC/AT use a 500KB/s floppy controller (high-speed) by default.

That doesn't mean that 1,44 MB drives can't be used, however. They can be used as substitutes for 720 KB types.

Ideally, they're operated with HD media, though.
So it made sense that HD floppies with the covered hole were used.
HD floppy+HD drive is fine, no matter the formatted capacity. 360KB formatting would fine, too.

A DD floppy can also be used read-only, just fine. If it was being written to by a DD drive, originally.
Problems merely occur, if the wrong drive/media was involved in a write operation.

Edit: Another thought: If the Gotek can be physically installed as an 1:1 replacement,
it might be possible to just use the built-in copydisk utility.
A replacement firmware like Flash Floppy or HxC can support a variety of floppy formats just fine.
If it works, this would perhaps be the most straightforward and clean solution.

Edit: Another idea, use a floppy disk emulator (not floppy drive emulator).

Source: https://en.wikipedia.org/wiki/FlashPath

If you're lucky, these old fake floppies with MMC or Smart Media slot can simulate a a real floppy disk well enough.
Then, you can try to dump the data of the flash card. Make an image with Win32DiskImager and extract the floppy data with a HexEditor or WinImage.

Edit: Another idea. The XTIDE Universal BIOS (XUB) has a serial boot feature.
If it's somehow possible to get XUB into the system, a hard disk can be simulated on a remote PC.
XUB has an optional utility that simulates HDD. Just don't forget to run the config program, because the XUB binary must be configured once before first use.
Anyway, it's just an idea, assumed that the device is based on regular PC technology.

Edit: Another idea, but it's a far fetch.
Use a Windows 2000 or XP with a real floppy drive controller and a matching drive.
Then install OmniFlop floppy replacement driver and use Emulator Explorer.

http://www.shlock.co.uk/Utils/OmniFlop/OmniFlop.htm

http://www.emulators.com/explorer.htm

Edit: Another idea. You need two floppy drives, a blank floppy and a DOS PC, though.
This hack might work better with non-standard floppy drive speeds than OmniFlop.

http://www.oldskool.org/disk2fdi/trial.html

https://www.youtube.com/watch?v=GOp-_Tmo4TE

Remember that floppies:
- Don't have to be formatted at 512 bytes per sector. Maybe those floppies are formatted at 256 bytes per sector.
- Don't have to start sector numbering at 0.

If you've got a internal floppy disk (=not USB!), you may try samdisk to dump them. Note that "raw" disk images don't store sector numbering or size... you should use EDSK file format to store it. Also, Gotek usually supports only PC disks (80 tracks, 2 sides, 9 or 18 sectors per track and 512 bytes per sector)... you'll need HxC for that.

I suppose the best approach is to use what is available, rather then spend money - if ultimate goal is to replace the FDD with something like Gotek (with HxC firmware?) then it should work no matter if the floppies are readable on a PC or not. After all these floppy emulators work at signal level and don't care about format, all that's required is for the original drive to use MFM (FM might also be supported) and 250/300/500 kbps bitrate. And getting the wiring correct - and that's it.

Reading the floppies on a PC is another problem entirely. If this machine uses PC-like FDC just not a typical PC format then just stick the floppy into a DOS machine and use IMD or something else that does low-level sector reads. Getting the HD hole correct for PC drive sensor might be required but otherwise it should work. The reason for that is the 3.5" drives that do 77 steps are 135TPI like typical PC ones - or at least I'm not aware of any other ones, those would be rare and a serious problem (though again, not for a drive emulator, it doesn't care).

If the format is not PC-controller compatible at all then there's the direct flux read/write method, that even can work around the 300/360 rpm problem without having a dual-speed drive. The data timebase is simply re-scaled and corrected in software. I use Greaseweazle V4, not only it's cheap but also open-source - hardware too, though frankly unless you are unlikely to come up with your own PCB and set of parts cheaper than ebay offers. Raw flux data can be converted to something sector-based if necessary for extracting files.

Looking at SAMdisk formats...

.lif — HP Logical Interchange Format (77/2/16/256).

Does it ring any bell?

Never heard of that format before.
Though HP-IB (GPIB) rings a bell. It was an interface standard for lab equipment.
https://en.m.wikipedia.org/wiki/IEEE-488

256 bytes per sector would actually explain DD media, it would work nicely at 250 kbps and fit on a track. However all DOS versions were hardcoded to 512 bytes per sector IIRC, and while some JP machines worked around that and used special, modified kernel, all of these had sectors of 512 or more bytes. Not less. So this format might not be readable by PCs (that is, low-level sector dump might still work, data extraction would require manual setup of disk parameters using a program like DiskExplorer).

Found something.

"Logical Interchange Format (LIF) Storage Structure and Information:

LIF is the format used to store data on the HP-IL storage devices (tape or disk). A discussion of LIF can be found on-line at ftp://fcext3.external.hp.com/dist/mxd/pc/old/lif_over.html.

LIF storage is fairly simple to understand. The first implementations of this system were on tape, so it makes even more sense. At the start of the tape –or disk– space is set aside on the media for the directory: to record how many files there are, what are their names, where they are located, how long they are, whether they’ve been deleted or not, etc. After the directory space comes the files stored one right after the other, like on a tape. One thing about LIF, it’s entirely one-dimensional: there aren’t any of those confusing (or useful) hierarchical directory structures. There’s just the files, one right after the other. Of course, LIF must include other details like the volume label, the number of bytes per record, number of records per file, trying to write a new file over the space vacated by a deleted file, etc, etc, but these are not important to this paper. So on the disk (or tape), there’s the directory and there’s the files.

[..]

HP LIF2DOS Software

As time has shown, LIF did not take the world by storm, did not become the de facto standard for disk storage format, and "…increasingly became a relic." (Read HP support’s version of this at ftp://fcext3.external.hp.com/dist/mxd/pc/old/lif_over.html). To extend the life of their product, HP worked up a software package that would allow DOS systems to read LIF-formatted floppies. They called it the HP E2080 LIFUTIL which, although now obsolete, they still remember. HP has thankfully "public domained" this software product, and is giving it away. Refer to http://www.tmo.hp.com/tmo/support/English/OSK … 991:020043.html for HP’s word. There will be a link there to follow for your own LIFUTIL software. Download a copy of this software, and set it up so that it can be run on your computer. This is the software that will be used to copy files between DOS and HP-IL!

This is a super software product that will allow you to read and write to a LIF disk from your DOS computer. Despite what HP says about it, it has worked fine for me on Intel 486 and Pentium Processors. "

https://www.hpmuseum.org/cgi-sys/cgiwrap/hpmu … les.cgi?read=24

This looks like a paying gig for a factory. In that case why not contct the source and you know, pay for support 😀
https://hxc2001.com/download/floppy_drive_emu … tor/support.htm
https://torlus.com/floppy/forum/
if you want something local you can try https://lotharek.pl

Thank you all for the input. I didn't expect so many people interested in this topic. 😀

It is possible the device is of East Germany origin.
I just tried ImageDisk 1.19 and it can read the floppy into image file. It indeed detects the sector size as 256B. There are 3 bad sectors (perhaps on purpose?). The good news is the image can be written to empty floppy by ImageDisk 1.19 on regular Pentium DOS PC..... and the new floppy works on the machine. So now I can at least store both image safely and create new floppies on any PC when needed. 😀

My next step will be to connect the Gotek to the machine and try to clone the original floppy onto it. I will try later today and report back how it went.

VgaCopy also has a driver called vgaread.exe that enables more formats on DOS, but I'm not sure whether it helps here.
Now you know the disk format, you may try SRDISK. It's a ramdisk driver that allows you to format the ramdisk with exactly that properties your disk has (as far as the disk just uses one sector size for all sectors). So you can setup sector size (128, 256, 512, 1024, ... bytes), cylinders, heads, sectors. Then you can copy your image to that ramdisk and try to play with it (disk editor, ...)
Just an idea...

With VgaCopy you also can increase the number of retries to retrieve that bad sectors.
As disk editor I use nu.exe from Norton Utilities 4.5 Advanced Edition. With nu /m it may be possible to retrieve parts of a bad sector.

Deunan wrote on 2023-04-13, 18:51:

However all DOS versions were hardcoded to 512 bytes per sector IIRC.

Try SRDISK ramdisk and you see that it is no problem for DOS to handle different sector sizes - at least in a ramdisk.

The "dos-65" version string is a smoking gun, this is likely either a DOS/65 variant (ie based on a 6502 CPU), or some CPM based system.

If it's CPM, then you should be able to find some tools to open and edit the contents of the image files, I know there are some on Linux. I don't know what Dos/65 uses.

Success! 😁

I managed to flash the FlashFloppy firmware on the Gotek. Configured it according to the drive geometry (77 cylinders, 16 sectors, 2 heads, 256B per sector). Then I created empty floppy images with this format by HxCFloppyEmulator and put two of them on the flash drive.

After that I connected the Gotek to my Pentium PC and restored the previously saved images with ImageDisk to the Gotek drive. I was a bit surprised to see no errors 😁

And as the last step - I replaced one of the floppy drives in the machine and everything works perfectly. In the end it was not as painful as thought it would be 😀

Thanks everyone for the good advices. 😀

Well done, congratulations! 😎👏