Help with recovering MED modules from corrupt floppy disks

milivella · 11 March 2015, 00:44

Hi. I'm asking for tips about recovering some MED files from floppy disks. First I'll give the needed details, then I'll tell you what I've planned to do, and finally I'll ask whether such plan can be improved. I won't necessarily reply to posts in this thread (I'll try to do it, though), but I'll ponder all suggestions. If there's something wrong in what I'm doing, please ignore/delete this post. Thanks in advance.

=The details=

Between 1994 and 1998, I owned an Amiga, and I composed 200+ little OctaMED modules on it. There usually isn't much redundancy in these modules:
- I didn't use to copy-paste a track in more than one block
- I didn't use the exact same sample in more than one song
Since 1999, I haven't owned an Amiga anymore; I own a PC.

The mentioned modules are stored in 17 floppy disks. I haven't kept them in optimal conditions. They have never been accessed since 1999, with one exception.

Said exception is that in 2009 a friend of mine offered to extract the modules from the disks, so that I would be able to open them e.g. with MED Soundstudio on Windows. When he found a disk with some bad sectors, he tried to read it with a different drive. He then used DiskSalv (or a similar utility, I'm not sure). He used Amiga drives, with no special controller. The final result was:
169 modules correctly extracted
53 corrupt non-empty modules; I don't know whether the file length is correct
9 empty (i.e. 0 bytes) modules
[note: there may be some modules that haven't been retrieved at all, i.e. not even the filename showed up, i.e. maybe I saved more than 222 modules]

The 62 (=53+9) non-OK modules were all in disks #9 to #15 (I used to start using a new disk whenever the previous one was full).

I think it could be useful to show an example of the corruption. Beginning of a corrupt file:

4D 4A 44 31 00 07 1E 22 00 07 00 34 00 07 00 00 00 07 07 68 00 07 00 00

00 07 03 48 00 07 00 00 00 07 08 90 00 07 00 00 00 07 00 00 00 07 00 00

FF F8 00 00 00 07 00 42 00 07 40 00 00 07 00 00 00 07 40 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 21 00 07 40 00 00 07 00 00

00 07 40 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00

00 07 00 00 00 07 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Compare it with the beginning of two non-corrupt files.

Non-corrupt file #1:

4D 4D 44 31 00 01 2E AA 00 00 00 34 00 00 00 00 00 00 6F 74 00 00 00 00

00 00 03 48 00 00 00 00 00 00 71 86 00 00 00 00 00 00 00 00 00 00 00 00

FF FF 00 00 00 00 00 00 00 00 40 02 01 EC 00 10 00 00 40 01 00 00 00 00

00 00 38 01 01 54 08 4E 00 00 38 02 00 00 00 00 00 00 38 01 00 19 0A B6

00 00 40 00 00 00 00 00 00 00 40 00 00 00 00 02 00 00 40 00 00 00 00 00

00 00 40 00 00 00 00 02 00 00 40 00 00 00 00 00 00 00 40 02 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 02 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 24 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Non-corrupt file #2:

4D 4D 44 31 00 00 AF A4 00 00 00 34 00 00 00 00 00 00 07 64 00 00 00 00

00 00 03 48 00 00 00 00 00 00 08 5E 00 00 00 00 00 00 00 00 00 00 00 00

FF FF 00 00 00 00 0B EB 00 00 40 00 00 00 17 D6 00 00 40 00 00 00 17 D6

00 00 40 00 00 00 00 00 00 00 00 00 00 00 17 D6 00 00 40 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

I'd like to recover as many modules as possible.

I'm a totally newbie at recovering files from Amiga disks, and generally I'm not good at hardware things.

=The plan=

[all points in chronological order]

1. Buy a KryoFlux and a floppy disk drive.

2. For each disk containing non-OK files:
2.1. First read: produce just a stream file.
2.2. Second read: produce a stream file + an ADF file, setting the number of retries to 100.

[next steps assuming I haven't managed to recover all modules]

3. Load the stream file in WinUAE (if not possible: buy a CatWeasel and make WinUAE directly read the disks) and try to recover the files using:
3.1. X-Copy's nibble copy
3.2. the latest version of DiskSalv
3.3. Quarterback

4. Send the disks to a data recovery service.

5. Study the MED file format (see e.g. http://www.textfiles.com/programming...S/med-form.txt ) and try to fix the corrupt files by hand.

=The question=

What would you change in my plan?

Thanks.

adrdesign · 11 March 2015, 01:29

I´ve got the same problem with some of my old floppies, but 0 money. As I can use a real amiga, could this be a substitute for a kryoflux device?

http://eab.abime.net/showthread.php?t=72971

If so, how do you use it? No need to explain in depth, Im interested in the basic steps to recover a floppy.

Thanks in advance

milivella · 11 March 2015, 01:55

Quote:

Originally Posted by adrdesign

I´ve got the same problem with some of my old floppies, but 0 money. As I can use a real amiga, could this be a substitute for a kryoflux device?

http://eab.abime.net/showthread.php?t=72971

As I wrote, I'm a total noob. However, as far as I can understand, the Kryoflux controller lets you read the disks at a lower level than a normal Amiga drive controller. And lower-level reading is supposed to mean more chances to get a successful recovery. So, if I'm right, the answer is: no, it isn't a 1:1 substitute.

(the post you linked to is about a software to _read_ images, but we first have to create them, right?

)

Quote:

Originally Posted by adrdesign

If so, how do you use it? No need to explain in depth, Im interested in the basic steps to recover a floppy.

Again, I'm not qualified at all to answer... but here are my answers.

Recovering disks, generally:
http://archiveteam.org/index.php?tit...g_Floppy_Disks

How Andy Warhol's files were recovered (using both a KryoFlux and a real Amiga!):
http://studioforcreativeinquiry.org/...report_v10.pdf

Possibly useful links for your case:
http://www.amiga.org/forums/showthread.php?t=12175
http://www.amiga.org/forums/showthread.php?t=56296
However, I'm sure you can find better results just by doing a Google search.

A tutorial for KryoFlux:
http://goughlui.com/2013/04/21/proje...ated-hardware/
6 parts, the last one being
http://goughlui.com/2013/05/19/proje...ks-and-drives/

daxb · 11 March 2015, 15:52

I would ask someone with good skills in recovering data from floppy disk and knows the med format. If you still have access to the samples you used back in the days it might be possible to load the samples into the mod if at least the pattern data + sample names are vailed. In this case corrupt samples aren`t a big problem.

On the other hand it is careless not having a backup of your work. Why? Wasn`t it worth to preserve it? Did you thought the data on floppy is save and survive many years?

In the nineties I accidentally formated a disk full of my mods. I could kill myslef when I noticed that and still regret that.

Seblington · 11 March 2015, 19:01

Heres a handy tip, My Protracker and Octamed files were corrupt, the floppy drive was making a real horrible screaming noise when attempting to read, looking at the floppy, I could see it was marked with very fine mold. I did find a solution to extract the files, isopropyl alcohol, a few drops on the surface of the disk either side and it read perfectly.

There is a down side to this, the dirt may not come off but if it does, it goes on the heads so its a good idea to get a disk cleaner too, this isn't a long term solution, but a sort term aimed at getting data back.

Note that this does no long term damage to the disk or computer, isopropyl is very good stuff :-)

milivella · 11 March 2015, 19:14

First of all, thanks for replying.

Quote:

Originally Posted by daxb

I would ask someone with good skills in recovering data from floppy disk and knows the med format.

Good suggestion. I don't know where to find such a person, though. I've asked all the data recovery services I was able to find, and nobody told me they had such skills (the replies were either "we can't help you" or "we have a KryoFlux/SuperCard Pro").

Quote:

Originally Posted by daxb

If you still have access to the samples you used back in the days it might be possible to load the samples into the mod if at least the pattern data + sample names are vailed. In this case corrupt samples aren`t a big problem.

Right, I should have specified this: I used to modify (boost/filter/cut/etc.) the samples for each module, and I don't have a copy of the samples outside the modules.

Quote:

Originally Posted by daxb

On the other hand it is careless not having a backup of your work.

It goes without saying that you're totally right. If I could slap past-me, I would do it for days.

Quote:

Originally Posted by daxb

Why? Wasn`t it worth to preserve it? Did you thought the data on floppy is save and survive many years?

Past-me had a... zen vision of the world, according to which it was OK for things to be transient. Or maybe I was just young and stupid.

milivella · 11 March 2015, 19:26

Quote:

Originally Posted by Seblington

Heres a handy tip, My Protracker and Octamed files were corrupt, the floppy drive was making a real horrible screaming noise when attempting to read, looking at the floppy, I could see it was marked with very fine mold. I did find a solution to extract the files, isopropyl alcohol, a few drops on the surface of the disk either side and it read perfectly.

There is a down side to this, the dirt may not come off but if it does, it goes on the heads so its a good idea to get a disk cleaner too, this isn't a long term solution, but a sort term aimed at getting data back.

Thanks a lot for the tip. I opened the slider of the seven problematic disks and quickly glanced at both sides, and I didn't see mold. In two of them I saw a very little white spot: can it be mold? Anyway, I guess it would cost me nothing trying isopropyl after the first attempt at reading the disks.

By the way, I saw scratches in three disks. Argh! Is this a hopeless situation?

Quote:

Originally Posted by Seblington

Note that this does no long term damage to the disk or computer, isopropyl is very good stuff :-)

I know.

[ Show youtube player ]

milivella · 12 March 2015, 09:02

One more question: is it possible (using a KryoFlux) to mark defective _bytes_ (not sectors or something else)?

E.g. in my corrupt file above I'd like to have the highlighted bytes automatically marked:
4D *4A* 44 31 00 *07* [etc.]

Seblington · 12 March 2015, 10:13

Light scratches on the surface of the disk are not to worry about, the white spot sounds like mold, as long as the scratches haven't distorted the surface of the disk you should be OK. My main hobby of old reel to reel tape recorders see's white mold all the time, on audio stuff, the mold clogs the heads but also causes head screech, in a computer it would completely disguise any signal the heads are trying to pick up, the Isopropanol (( sorry last one was spell checker), helps clean the disk, dislodge the mold but also act as a temporary lubricant reducing head screech and giving a better signal output.

milivella · 12 March 2015, 15:15

Quote:

Originally Posted by Seblington

Light scratches on the surface of the disk are not to worry about, the white spot sounds like mold, as long as the scratches haven't distorted the surface of the disk you should be OK. My main hobby of old reel to reel tape recorders see's white mold all the time, on audio stuff, the mold clogs the heads but also causes head screech, in a computer it would completely disguise any signal the heads are trying to pick up

Thanks for replying. Let me sum up my current opinion about the issue, so that you can tell me if it's wrong:
1. I don't know whether these scratches qualify as light (but I hope so!).
2. The white spots I saw look too little to corrupt up to 15 files in a disk (I know that in some cases it takes just a bad byte, but...). Of course I looked at just a fraction of the disk (I didn't spin it), so maybe there are more/bigger spots.
3. #1 and #2 don't really matter, since (1) I can do nothing against scratches and (2) using a bit isopropyl alcohol won't harm the disks, so what I will do is independent from the truth about scratches and mold: I'll clean the disk with the help of IA and try to read it.

ElectroBlaster · 13 March 2015, 23:12

Any chance of getting some pictures? It will be a little difficult with some faffing about.

I can vouch for ISO Alcohol! it works and works well. I did this with some VERY old Atari ST disks. I sat with each disk holding one of those cotton ear bud stick things and spent ages cleaning the whole surface of both sides of the recording surface. Allowed it to dry, helping this along with a clean dry ear cleaner thingy gently mopping it.

So the first initial read pass was not brilliant but you could see things were getting better. The results were good and after a couple re-reads I got 100% read. The goal was just to get the data off intact.

I have a Catweasel mk4, Kryoflux and of course real amiga's.

Jope · 14 March 2015, 07:59

I just gotta say, don't scrape off the mold with the r/w head.. Take the disk out of the case, clean it carefully with cotton pads/swabs and ipa, reassemble enough that you can reinsert it and then read the disk..

milivella · 14 March 2015, 19:56

Quote:

Originally Posted by ElectroBlaster

Any chance of getting some pictures?

Unfortunately I can't get better pictures than the one I'm attaching, that - I guess - it's useless (if it isn't, I can add some more).

Anyway, the disk in the pictures is among the ones with the little white spots (the spot is highlighted in the second picture). As of the scratches... I can't see them anymore in any disk?!

Thanks for the reply. Also thanks to Jope.

milivella · 23 March 2015, 17:32

[I posted this message on the KryoFlux support forum as well]

I've just bought a KryoFlux, and I like it very much. Unfortunately, I haven't managed to make it recover the disks. Let me remind that they are partially unreadable on real Amigas: as a matter of fact even after using DiskSalv to write a repaired copy of the disk, some of the files still came out corrupt.

(1) Now, when I just generate a stream file of the disks, without the format check*, DTC tells me that the reading of some sectors is uncertain. E.g.

Code:

06.0    : frev: 48524, drift: 0.924 us, tfer: 233138 B/s, rpm: 300.651
06.0    : band: 3.956 us, 5.941 us, 7.777 us?

* dtc -f09a -i0

(2) But when I ask DTC to do the format check and retry up to 100 time if there's an error** (same drive as #1), it doesn't retry to read those tracks (or so it seems to me, since all track readings last the same), and tells me that they're OK even if it the reading still isn't sure:

Code:

06.0    : frev: 48524, drift: 0.125 us, tfer: 233138 B/s, rpm: 300.665
06.0    : band: 3.956 us, 5.942 us, 7.791 us?
06.0    : base: 1.981 us [98.271%], band: 3.956 us, 5.942 us, 7.791 us?
06.0    : AmigaDOS: OK, trk: 012, sec: 11

As a matter of fact, the modules that the real Amigas didn't manage to read are still unreadable in the generated ADF file (tested in WinUAE).
** dtc -f09b -i0 -f09b.adf -i5 -t100

Indeed, I made DTC read each disk from a different drive, and the two generated ADF files of the same disk are byte-by-byte identical.

Now, my questions are:
- Is it wrong to assume that the tracks with the question mark are the ones with corrupt data?
- Shouldn't DTC try to read the tracks with corrupt data (whichever they are) 100 times when I add the -t100 option? Shouldn't it mark as non-OK in the end, since the result includes some corrupt files?
Thanks.

Jope · 23 March 2015, 18:39

Try to add more revolutions per track, perhaps it can get more out of it that way. :-)

milivella · 23 March 2015, 19:41

Quote:

Originally Posted by Jope

Try to add more revolutions per track, perhaps it can get more out of it that way. :-)

Thanks, I'm trying it right now (50 revolutions).

milivella · 23 March 2015, 20:25

Quote:

Originally Posted by milivella

Thanks, I'm trying it right now (50 revolutions).

First disk: the resulting ADF is still exactly the same.

ElectroBlaster · 24 March 2015, 22:57

Do you have an External drive?

XCopy pro may help out. Copying using DOSCOPY+ mode could well fix it or fix it enough to get a decent ADF.

I have no love for TDK disks! We never really trusted them back in the day. They would crap out and garble up data. Never did suss out why!

EDIT: Your pictures appear to show the inner surface of the disk looks clean.

Jope · 25 March 2015, 05:49

I love TDK disks, they worked fine back in the day, and many of them still do. Sony (!), BASF, JVC and various no-name brands were always broken for me.

milivella · 25 March 2015, 19:20

Quote:

Originally Posted by ElectroBlaster

Do you have an External drive?

I have a Sony MPF920 and a Samsung SFD-321B, that I connect to my PC via the KryoFlux. I have not an Amiga (would it be useful?).

Quote:

Originally Posted by ElectroBlaster

XCopy pro may help out. Copying using DOSCOPY+ mode could well fix it or fix it enough to get a decent ADF.

I did it in WinUAE:
X-Copy
DF0 = ct raw image of bad disk
DF1 = blank "custom" disk
DOSCOPY+, source DF0, destination DF1

...but the result is still unreadable files.

Maybe the reason is that the checksum on the bad disks is OK (this is the reason why the KryoFlux doesn't see them as bad). And I don't know why it is OK! The only possible explanation is that my friend used DiskSalv repair directly on them (as opposed to a copy), but I'm pretty sure he didn't.

Quote:

Originally Posted by ElectroBlaster

I have no love for TDK disks! We never really trusted them back in the day. They would crap out and garble up data. Never did suss out why!

Out of curiosity...

Disks that are OK:
7 TDK
2 [no brand]
1 Moviola

Disks that are not OK:
5 [no brand]
2 TDK

Quote:

Originally Posted by ElectroBlaster

EDIT: Your pictures appear to show the inner surface of the disk looks clean.

I really don't know what's the problem!

I guess it's a good time to update my situation. Here's my original plan (updated because of your suggestions), and what I have done.

1. Buy a KryoFlux, a Samsung SFD-321B and a Sony MPF920.
I did it.

2. For all disks containing non-OK files: 1) produce just a stream file; 2) produce a stream file + an ADF file, setting the number of retries to 100; 3) same as #2, with a different drive; 4) same as #2, with 50 revolutions per track.
I did it. The Kryoflux sees the disks as OK. All the three ADF files produced by the KryoFlux are byte-by-byte the same. I.e. the KryoFlux sees that the disks contains exactly the corrupt files.

3. Isopropyl alcohol on the surface of the disk either side [etc.]
I didn't do it, since the surface looks clean.

4. Create a CT Raw file from the stream, load it in WinUAE and try to recover the files using: 1) X-Copy's nibble copy, 2) X-Copy's doscopy+, 3) the latest version of DiskSalv's repair and salvage, 4) Quarterback.
I did it and the result is...
1) unreadable (by WinUAE) disk image
2) readable disk image with unreadable (by OctaMED) files
3) [I wasn't able to find a version of DiskSalv that works in WinUAE]
4) readable disk image with unreadable files
By the way, if I load the CT RAW files as disks in WinUAE they are all "readable disk image with unreadable files".

5. Send the disks to a data recovery service.
I don't know if it makes sense to do, since I don't know if they can do something that I can't.

6. Study the MED file format and try to fix the corrupt files by hand
7. Study the Amiga disk format and try to fix the corrupt data by hand
To do.

23 March 2015, 17:32	#14
milivella Registered User Join Date: Mar 2015 Location: Italy Posts: 13	[I posted this message on the KryoFlux support forum as well] I've just bought a KryoFlux, and I like it very much. Unfortunately, I haven't managed to make it recover the disks. Let me remind that they are partially unreadable on real Amigas: as a matter of fact even after using DiskSalv to write a repaired copy of the disk, some of the files still came out corrupt. (1) Now, when I just generate a stream file of the disks, without the format check, DTC tells me that the reading of some sectors is uncertain. E.g. Code: 06.0 : frev: 48524, drift: 0.924 us, tfer: 233138 B/s, rpm: 300.651 06.0 : band: 3.956 us, 5.941 us, 7.777 us? dtc -f09a -i0 (2) But when I ask DTC to do the format check and retry up to 100 time if there's an error (same drive as #1), it doesn't retry to read those tracks (or so it seems to me, since all track readings last the same), and tells me that they're OK even if it the reading still isn't sure: Code: 06.0 : frev: 48524, drift: 0.125 us, tfer: 233138 B/s, rpm: 300.665 06.0 : band: 3.956 us, 5.942 us, 7.791 us? 06.0 : base: 1.981 us [98.271%], band: 3.956 us, 5.942 us, 7.791 us? 06.0 : AmigaDOS: OK, trk: 012, sec: 11 As a matter of fact, the modules that the real Amigas didn't manage to read are still unreadable in the generated ADF file (tested in WinUAE). dtc -f09b -i0 -f09b.adf -i5 -t100 Indeed, I made DTC read each disk from a different drive, and the two generated ADF files of the same disk are byte-by-byte identical. Now, my questions are: - Is it wrong to assume that the tracks with the question mark are the ones with corrupt data? - Shouldn't DTC try to read the tracks with corrupt data (whichever they are) 100 times when I add the -t100 option? Shouldn't it mark as non-OK in the end, since the result includes some corrupt files? Thanks.

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11 March 2015, 00:44	#1
milivella Registered User Join Date: Mar 2015 Location: Italy Posts: 13	Help with recovering MED modules from corrupt floppy disks Hi. I'm asking for tips about recovering some MED files from floppy disks. First I'll give the needed details, then I'll tell you what I've planned to do, and finally I'll ask whether such plan can be improved. I won't necessarily reply to posts in this thread (I'll try to do it, though), but I'll ponder all suggestions. If there's something wrong in what I'm doing, please ignore/delete this post. Thanks in advance. =The details= Between 1994 and 1998, I owned an Amiga, and I composed 200+ little OctaMED modules on it. There usually isn't much redundancy in these modules: - I didn't use to copy-paste a track in more than one block - I didn't use the exact same sample in more than one song Since 1999, I haven't owned an Amiga anymore; I own a PC. The mentioned modules are stored in 17 floppy disks. I haven't kept them in optimal conditions. They have never been accessed since 1999, with one exception. Said exception is that in 2009 a friend of mine offered to extract the modules from the disks, so that I would be able to open them e.g. with MED Soundstudio on Windows. When he found a disk with some bad sectors, he tried to read it with a different drive. He then used DiskSalv (or a similar utility, I'm not sure). He used Amiga drives, with no special controller. The final result was: 169 modules correctly extracted 53 corrupt non-empty modules; I don't know whether the file length is correct 9 empty (i.e. 0 bytes) modules [note: there may be some modules that haven't been retrieved at all, i.e. not even the filename showed up, i.e. maybe I saved more than 222 modules] The 62 (=53+9) non-OK modules were all in disks #9 to #15 (I used to start using a new disk whenever the previous one was full). I think it could be useful to show an example of the corruption. Beginning of a corrupt file: 4D 4A 44 31 00 07 1E 22 00 07 00 34 00 07 00 00 00 07 07 68 00 07 00 00 00 07 03 48 00 07 00 00 00 07 08 90 00 07 00 00 00 07 00 00 00 07 00 00 FF F8 00 00 00 07 00 42 00 07 40 00 00 07 00 00 00 07 40 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 21 00 07 40 00 00 07 00 00 00 07 40 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 07 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 Compare it with the beginning of two non-corrupt files. Non-corrupt file #1: 4D 4D 44 31 00 01 2E AA 00 00 00 34 00 00 00 00 00 00 6F 74 00 00 00 00 00 00 03 48 00 00 00 00 00 00 71 86 00 00 00 00 00 00 00 00 00 00 00 00 FF FF 00 00 00 00 00 00 00 00 40 02 01 EC 00 10 00 00 40 01 00 00 00 00 00 00 38 01 01 54 08 4E 00 00 38 02 00 00 00 00 00 00 38 01 00 19 0A B6 00 00 40 00 00 00 00 00 00 00 40 00 00 00 00 02 00 00 40 00 00 00 00 00 00 00 40 00 00 00 00 02 00 00 40 00 00 00 00 00 00 00 40 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 02 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 24 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 Non-corrupt file #2: 4D 4D 44 31 00 00 AF A4 00 00 00 34 00 00 00 00 00 00 07 64 00 00 00 00 00 00 03 48 00 00 00 00 00 00 08 5E 00 00 00 00 00 00 00 00 00 00 00 00 FF FF 00 00 00 00 0B EB 00 00 40 00 00 00 17 D6 00 00 40 00 00 00 17 D6 00 00 40 00 00 00 00 00 00 00 00 00 00 00 17 D6 00 00 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 I'd like to recover as many modules as possible. I'm a totally newbie at recovering files from Amiga disks, and generally I'm not good at hardware things. =The plan= [all points in chronological order] 1. Buy a KryoFlux and a floppy disk drive. 2. For each disk containing non-OK files: 2.1. First read: produce just a stream file. 2.2. Second read: produce a stream file + an ADF file, setting the number of retries to 100. [next steps assuming I haven't managed to recover all modules] 3. Load the stream file in WinUAE (if not possible: buy a CatWeasel and make WinUAE directly read the disks) and try to recover the files using: 3.1. X-Copy's nibble copy 3.2. the latest version of DiskSalv 3.3. Quarterback 4. Send the disks to a data recovery service. 5. Study the MED file format (see e.g. http://www.textfiles.com/programming...S/med-form.txt ) and try to fix the corrupt files by hand. =The question= What would you change in my plan? Thanks.

11 March 2015, 01:29	#2
adrdesign Registered User Join Date: Nov 2013 Location: Spain Age: 45 Posts: 314	I´ve got the same problem with some of my old floppies, but 0 money. As I can use a real amiga, could this be a substitute for a kryoflux device? http://eab.abime.net/showthread.php?t=72971 If so, how do you use it? No need to explain in depth, Im interested in the basic steps to recover a floppy. Thanks in advance

11 March 2015, 15:52	#4
daxb Registered User Join Date: Oct 2009 Location: Germany Posts: 3,304	I would ask someone with good skills in recovering data from floppy disk and knows the med format. If you still have access to the samples you used back in the days it might be possible to load the samples into the mod if at least the pattern data + sample names are vailed. In this case corrupt samples aren`t a big problem. On the other hand it is careless not having a backup of your work. Why? Wasn`t it worth to preserve it? Did you thought the data on floppy is save and survive many years? In the nineties I accidentally formated a disk full of my mods. I could kill myslef when I noticed that and still regret that.

11 March 2015, 19:01	#5
Seblington Amiga Nutter Join Date: Sep 2005 Location: Paignton, Devon. Age: 43 Posts: 220	Heres a handy tip, My Protracker and Octamed files were corrupt, the floppy drive was making a real horrible screaming noise when attempting to read, looking at the floppy, I could see it was marked with very fine mold. I did find a solution to extract the files, isopropyl alcohol, a few drops on the surface of the disk either side and it read perfectly. There is a down side to this, the dirt may not come off but if it does, it goes on the heads so its a good idea to get a disk cleaner too, this isn't a long term solution, but a sort term aimed at getting data back. Note that this does no long term damage to the disk or computer, isopropyl is very good stuff :-)

12 March 2015, 09:02	#8
milivella Registered User Join Date: Mar 2015 Location: Italy Posts: 13	One more question: is it possible (using a KryoFlux) to mark defective _bytes_ (not sectors or something else)? E.g. in my corrupt file above I'd like to have the highlighted bytes automatically marked: 4D 4A 44 31 00 07 [etc.]

12 March 2015, 10:13	#9
Seblington Amiga Nutter Join Date: Sep 2005 Location: Paignton, Devon. Age: 43 Posts: 220	Light scratches on the surface of the disk are not to worry about, the white spot sounds like mold, as long as the scratches haven't distorted the surface of the disk you should be OK. My main hobby of old reel to reel tape recorders see's white mold all the time, on audio stuff, the mold clogs the heads but also causes head screech, in a computer it would completely disguise any signal the heads are trying to pick up, the Isopropanol (( sorry last one was spell checker), helps clean the disk, dislodge the mold but also act as a temporary lubricant reducing head screech and giving a better signal output. Last edited by Seblington; 12 March 2015 at 12:34. Reason: repeated something already addressed.

13 March 2015, 23:12	#11
ElectroBlaster Junior Member Join Date: Mar 2002 Location: Exeter, Devon, UK Age: 49 Posts: 1,706	Any chance of getting some pictures? It will be a little difficult with some faffing about. I can vouch for ISO Alcohol! it works and works well. I did this with some VERY old Atari ST disks. I sat with each disk holding one of those cotton ear bud stick things and spent ages cleaning the whole surface of both sides of the recording surface. Allowed it to dry, helping this along with a clean dry ear cleaner thingy gently mopping it. So the first initial read pass was not brilliant but you could see things were getting better. The results were good and after a couple re-reads I got 100% read. The goal was just to get the data off intact. I have a Catweasel mk4, Kryoflux and of course real amiga's.

14 March 2015, 07:59	#12
Jope - Join Date: Jul 2003 Location: Helsinki / Finland Age: 43 Posts: 9,863	I just gotta say, don't scrape off the mold with the r/w head.. Take the disk out of the case, clean it carefully with cotton pads/swabs and ipa, reassemble enough that you can reinsert it and then read the disk..

23 March 2015, 18:39	#15
Jope - Join Date: Jul 2003 Location: Helsinki / Finland Age: 43 Posts: 9,863	Try to add more revolutions per track, perhaps it can get more out of it that way. :-)

24 March 2015, 22:57	#18
ElectroBlaster Junior Member Join Date: Mar 2002 Location: Exeter, Devon, UK Age: 49 Posts: 1,706	Do you have an External drive? XCopy pro may help out. Copying using DOSCOPY+ mode could well fix it or fix it enough to get a decent ADF. I have no love for TDK disks! We never really trusted them back in the day. They would crap out and garble up data. Never did suss out why! EDIT: Your pictures appear to show the inner surface of the disk looks clean.

25 March 2015, 05:49	#19
Jope - Join Date: Jul 2003 Location: Helsinki / Finland Age: 43 Posts: 9,863	I love TDK disks, they worked fine back in the day, and many of them still do. Sony (!), BASF, JVC and various no-name brands were always broken for me.

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