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To my knowledge there is only one program which can image all copy protected disks. Other programs may work on some disks, but it really depends on the protection.

 

Unfortunately, you need an Amiga to use this program. It is part of the preservation process at CAPS (http://www.caps-project.org). Don't let the name fool you, it will soon be changing into a much more generic society to preserve software for all systems, not just for the Amiga.

 

However, technical reasons dictate that you will never be able to use a normal Atari ST to properly image copy protected media.

 

If you do have access to an Amiga, we are CAPS are very interested in getting more dumps of ST games. We need about 100 more examples for our research before we can support the formats and protections used on the ST.

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BTW, if by "backup" you mean a disk-to-disk copy. Please note that these are very like copying a VHS video tape. Each generation copy degrades until very soon the game will stop working.

 

Even with these analogue copiers, some protections (including one we think was very often usedon the ST) will still fail.

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Re: copy (generation) degradation

That would be true if the data on disks was in analog form.

Even "disk to disk" copiers make use of buffers to hold the values of tracks being written. You can't really compare it to VHS copy degradation.

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There are a few copying programs for ST that can copy various copy protection schemes. However, they are few, and can't copy everything.

 

Due to limitations of the floppy controller used in Atari, you can't make an exact duplicate of the areas of the disk where the copyprotections are located.

 

But as with everything, there are ofcourse exceptions to this... :)

 

There exist hardware (Blitz copier, Synchro express) that connects two floppys together, and using the atari to control the duplication process, completely bypass the floppy disk controller, and copies directly from disk to disk. These can more or less copy anything you throw at it.

 

---

 

As to degradation of the copies... that's BS. The info on a floppy is digitally stored. Degradation of copies does not come from the copying process itself.

 

Reasons for bad copies are for the most part bad original disks, bad duplication scheme or even bad hardware/destination floppy.

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Nukey Shay & Greenious:

 

Sorry to inform you guys, but what I said was correct. Although the data stored on floppy disks is digital (being computer data) it is is stored in an analogue form, and so the analogy of VHS cassettes when releated to analogue hardware copiers is entirely correct.

 

Normal copying is different to the hardware copiers I mentioned because the computer reads the disk by interpreting the bitcells making up the flux transitions as 0's and 1's, checks all checksums match and holds that data to be subsequently written. It is "refreshed" and so "new" every time it is written.

 

However, in analogue copiers, there is no such buffering. They work by tightly synchronising two drives and the signals send from one disk to another is a pure analogue signal. There is no checking of itegrity (CRC, etc.), because the data is never actually "processed". This is the only practial way a consumer can try to copy protected disks and such a solution is cheap to develop and manufacture.

 

A disk copy produced by such a process is slightly less "quality" than the master. If you keep making generational copies like this the copy gets worse (just like a VHS tape) until the bitcells can no longer "hold together". Unfortunately, since it is digital data the result is that you get errors (bits are mis-read and even "bitshift", that is, corrupt neighbour bits because of their change of value), and likely the game will not work any more. Since VHS is analogue data by nature, you just get gradually worse picture/sound on each copy generation.

 

The trick to understanding the above is that what is recorded on floppy disks is not just the data, there are other sorts of information too. This information is essential is preserving copy protected software, and this is an area we at CAPS (http://www.caps-project.org) specialise in.

 

This is a very complicated subject area. But if you want to know more, search for "Magnetic Recording Theory" on Google.

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There exist hardware (Blitz copier, Synchro express) that connects two floppys together, and using the atari to control the duplication process, completely bypass the floppy disk controller, and copies directly from disk to disk.

 

Correct. Because the disks are copied in analogue. :) These are the analogue hardware copiers I mentioned. Cyclone is the most well known one on the Amiga.

 

These can more or less copy anything you throw at it.

 

They can copy many density protections, just as long as the timing is not too strict (for example, the Amiga version of Rob Northen's Copylock usually fails, and the ST version is quite similar). They can also copy disks with variations in disk format.

 

However, they cannot copy flakey bits (aka weak bits). You cannot blindly image this protection, because of the way it works. See here for more information: http://www.caps-project.org/articles.php?i...id=g_flakeybits. This type of protection looks so far very common on the ST and PC.

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Well, it was quite some time since I was playing around with copy protections on the ST, so I might have forgotten a thing or two. But one of the things I do remember is the ST floppy controllers inability to read complete tracks. It could read individual sectors fine, but reading a complete track was impossible to do accurately. Since that was the only way of reading what was in-between the sectors, and it is very unreliable, it always meant that you had to read & reread the track over and over again, and try to interpolate what was there.

 

I think that is the reason many believe that most protections on ST is based on flakey bits. When in reality the game is just trying to get a good read of it's copy protection patterns.

 

Anyway, 10 years ago I could have given you a complete rundown on this, but I don't remember this stuff accurately enough to stick my head out.

 

And I still claim that the degradation is BS. There are tons of factors involved in floppy duplication, but if your hardware is 100% working, you do indeed get a 100% copy.

 

But it is true that the floppy->floppy copying scheme in Blitz is more sensitive to different hardware used. Just using 2 different makes of diskdrives can be enough to make the copy slightly misaligned, and thus a bad copy. Sometimes the misalignment is still within specs, sometimes not, and copying several times also duplicates the misalignments, possibly enhancing them. Also, a floppy is supposed to spin at 300 rpm, but it is perfectly within specs if it spins at 295 or 305 rpms. So, there's plenty of room for errors.

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The reason I said it flakey bits "look very common on the ST" is because we have actually seen it. Of the 100 or so ST games dumped, there are quite a few that use flakey bit protection. Our technology allows us to see this sort of this very easily, and our dumping mechanism gets us bit-for-bit what it on the disk surface (plus other things asides from the data, like track geometry and cell density). Now whether this high proportion of flakey bit games dumped is by coincidence we do not currently know, and we won't know until we dump more, but this will happen in the near future...

 

Fortunately for us, it doesn't matter what is between in the gap areas, it all gets read as-is. As you state, you cannot use an ST to do this due to its FDC.

 

The degradation of bit cells is not BS. It is a fact. I don't mean to offend you, but it really is that simple... :) We have done a lot of research (a couple of years *full time*) in this area, and we know what we are talking about. This is not exactly a hobby project...

 

Anyway, you can read a little more about it (though it is currently focused on the Amiga "Cyclone" package, the principles are exactly the same) here: http://www.caps-project.org/faq.php?question=cyclone. Most of the information I have talked about here though.

 

What you say about copies is missing the point. If you copy a disk with a hardware copier, it may indeed be a 100% copy of the *data* (or it may not - basically it is less and less likely to be a 100% copy, the more generations you use) but the properties of the disk will not be - that is guaranteed. I stress this, though the *data* may remain the same for some generations of the copy, the properties of the disk do not. The bitcells will not "hold together" in later generation copies. Since we can see the properties of a disk, we can actually see this happening.

 

I think you are focusing too much on the data you store on a disk. You should be thinking more along the lines of how that data is made up, i.e. magnetic particles, that make up the bit cells, that make up flux transitions, which make up the encoding/clocking, that make up the actual bits you want to store. The data stored is only the "top layer" in the chain. It is the lower-level properties that change (which will result in actual data change eventually) and this is exactly the reason why we do not accept hardware-copy submissions to CAPS. If people don't know they are hardware copies, it doesn't matter, because we can actually see whether they are or not.

 

Another side effect of hardware copies is that they are more prone to bitrot (http://www.caps-project.org/articles.php?id=g_bitrot) for for similar reasons as above. Because the bitcells are not quite as "healthy" as the originals, they are more likely to be mis-read as time goes by.

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I copied several ATARI ST disks with the AMIGA Cyclone and all the copies, usually early-90s games, worked.

 

But the Cyclone copy only works with a small hardware add-on and copying can take some time.

Cyclone is very good, copies 80% of AMIGA games, BUT the result depends on your disk drives.

 

Older 80s games can be copied with old copy programs like "A-Copy" (used this to backup my original Bard's Tale).Some very old games can be copied by removing PRG in the Auto Folder.

This worked with my copy of "Championship Wrestling", the program checking the copy-protection was in the AUTO Folder and not necessary for the game.

 

BTW : Re-Releases under budget labels like KIXX or Hit Squad often have no copy protection.

 

Thimo

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Actually, I did some travelling down memory lane and dug up some of my old notes on copy protections... Phew...

 

I don't remember that protection scheme being that common, (I referred to it at that time as Fuzzy sectors or Phantom sectors) if it was, I'd remember it better I think. :)

 

Anyway, that protection is easily mistaken for the duplicate sector protection, since they behave in a similar way, and you can probably emulate the "flakey" bits too using the dupe sector scheme. (Or people mistake the flakey bits with the dupe sector scheme.)

 

What you do is to format the track with several sectors with the same adress id. Thus, when you read that particular sector, the contents will differ depending on which one of the dupe sectors you end up reading. Used in conjunction with other tricks, a full track can have a seemingly limitless amount of duplicated sectors (minimum 2 to a maximum of 50-60 I think).

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@tjlazah

 

Great! Please email contributions@caps-project.org' date=' and we will sort you out with all the software you need and take you through the process.

 

The same goes for anyone else of course. :)[/quote']

 

Well I went to the site but it seems it was tools for making backups of Amiga disks for CAPS, I want to copy Atari ST disks. Can I make a CAPS image of a ST disk with the Amiga CAPS diskmaker? Once I make the image, how do I write it back to another disk?

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The technology is generic, we were just concentrating on Amiga in the beginning. We developing a more generic website at the moment, which should go live in a few months. The resulting disk images are called IPF's - (Interchangeable Preservation Format) for a reason. :)

 

You cannot currently write these images back to disk. We do have plans for a commerical quality mastering solution, but it will take a lot of time and money we do not have to devote to it right now.

 

The point is getting the disks preserved in the first place, we then do not have to worry about them dying, because they will eventually!

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Absolutely. It is done with UAE and support is apparently being added to Fellow too. It shouldn't be too difficult and there is very extensive documentation to help. We provide a library to interface to the disk images, so a lot of the work is already done.

 

The only real barrier is the need for very accurate / low level emulation of the FDC. This is something we planned to help with, but it may actually already be in progress.

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  • 9 months later...

Re: analog copiers

They can copy many density protections, just as long as the timing is not too strict (for example, the Amiga version of Rob Northen's Copylock usually fails, and the ST version is quite similar)

 

You are wrong Fiath. Analog copiers easily can reproduce the variable bit rate of ST Copylock (and probably the Amiga version as well). The reason that it usually fails is because the software can easily identify a copy made with an analog copier, but NOT because of the bit-rate (density). Some earlier Copylocked programs don’t have this check and then the program runs fine. Most later ones added this extra check and then they fail.

 

I think that is the reason many believe that most protections on ST is based on flakey bits. When in reality the game is just trying to get a good read of it's copy protection patterns.

 

Weak bits is a more or less common protection in US releases (but not the most popular). It is rarer on euro releases. Most euro protections are based on bit-rate variations. The reasons that checking the copy protection sometimes seems to be slow are several.

 

Most european protections are encrypted with the Copylock packer. At runtime, the decryption is done by tracing each CPU instruction. Each instruction is individually decrypted at the exception handler and the previous one is re-encrypted. This obviously is very slow.

 

Some protections are run in seudo-code using a custom interpreter. This is also slow.

 

As you said some protections need to be retried to be confirmed, but not many times, usually only twice. Reading the inter-sector data requires many passes when is done by a copier that doesn’t know what and where the protection is. The protection itself usually don’t need many attempts.

 

And I still claim that the degradation is BS. There are tons of factors involved in floppy duplication, but if your hardware is 100% working, you do indeed get a 100% copy.

 

Fiath is correct here. The degradation of the signal when using an analog copier is true. The data on a floppy might be digital, as is indeed the case of unprotected disk and even on many protections. But this is not the point. The point is that you are using an analog process. Multi-generation copies made with an analog copier fail faster than you think. And is also true that floppies recorded with an analog copier has more chances to develop data corruption, mainly because no pre-compensation is performed.

 

However all the problems associated with an analog copier disappear if you use a hardware digital copier such as the Discovery Cartridge, Catweasel, Copy II PC Option board, etc.

 

I don't remember that protection scheme being that common, (I referred to it at that time as Fuzzy sectors or Phantom sectors) if it was, I'd remember it better I think.  

 

Anyway, that protection is easily mistaken for the duplicate sector protection, since they behave in a similar way, and you can probably emulate the "flakey" bits too using the dupe sector scheme. (Or people mistake the flakey bits with the dupe sector scheme.)

 

This “emulation” would work only in naive implementations of the protection. The protection can easily check if there aren’t multiple (dup) sectors, it can verify that all the rest of the sectors are full and present. And it can sync the reading of the weak sector to make sure he is always reading the same physical sector.

 

There are indeed some naive implementations that allow this kind of emulation. And sometimes software copiers can make a working copy of a disk with weak bits. Most of the cases the protection is smarter and there is nothing you can do with a software copier (except cracking).

 

Protections actually based on double/duplicate sectors are very rare on the ST. The main reason is that this protection can easily be copied with a software copier. I recall only some earlier US titles and some french ones. It is possible to combine double sectors with other variation, and then make a protection that you can’t copy with software. This was very popular in the 8-bit. But I don’t recall to see this on the ST, probably because it doesn’t make much sense in the ST as in the 8-bit.

 

The probable reason why you don’t recall weak-bits too much is, because as said above, it is more common in US than in Euro releases. But it is not as common as Fiath believes either. Not everything that looks “weak” is actually a weak-bits protection.

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  • 3 weeks later...

Not this old chestnut ;)

 

You are wrong Fiath. Analog copiers easily can reproduce the variable bit rate of ST Copylock (and probably the Amiga version as well). The reason that it usually fails is because the software can easily identify a copy made with an analog copier, but NOT because of the bit-rate (density). Some earlier Copylocked programs don’t have this check and then the program runs fine. Most later ones added this extra check and then they fail.

 

The Copylock bit cell density track when copied using an analog copier was considerably messed up when tried it. So to say it doesn't work because of that is probably the reason - and I tried it on both old and newer versions of Copylock on the Amiga. It may of course be different on the ST version.

 

You are wrong again, they can copy weak bits. By this time you probably learned that weak bits are not what you thought. So you can understand why it is not a problem for analog copiers.

 

Again I am not wrong. Flakey bits as we define them do exist: on the Amiga. I guess from your statements that they do not exist or are at least far more rare on the ST. What I said above has been seen in practice, a game that checks for these "flaky" bits on an analogue-copied game fails because the bits are no longer changing, exactly as we describe on the site. Analogue copiers cannot reproduce this. However yes, it is perfectly true to say that I was not aware of the techniques causing a similar effect, not that it really matters.

 

The probable reason why you don’t recall weak-bits too much is, because as said above, it is more common in US than in Euro releases. But it is not as common as Fiath believes either. Not everything that looks “weak” is actually a weak-bits protection.

 

Perhaps I was wrong about saying they were more common on the ST/PC. They are very common on the Amiga either - and a very small minority when compared to all the games with density-type protections. But they are not extremely rare either - on the Amiga. Obviously the two systems are not very comparable, which is surprising since the same equipment was often used to do the mastering.

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OK I have had some success in copying protected titles! I have a lot of original disks and some of my disks are going bad. No surprise as they are over 20 years old. I was looking to make working backups since I have a lot of DSDD disks, and that way if my original goes back I have a backup! I used ACopy and ProCopy 1.80 and it seems to work with most games. I made backups of The Pawn, Guild of Thives, Road Runner, Indiana Jones, and some others so far. I do have a few disks that are bad: Ghosts 'N Goblins, Lords of Conquest, Leathernecks. Anyone have these originals that would not mind making a backup copy for me? I don't feel like waiting for the next century when Caps will be able to help me. Thanks.

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re: copying commercial disks using software based copiers

 

Very much a hit and miss affair, you'd be better off (if you have an ST/e) is to get the happy discovery cartridge) this is basically the ST version of the famous Atari 8bit disk drive upgrade, the only difference is the ST version is self contained in a cartridge which means, unlike the atari 8bit version you don't need to open up your ST/e and start mod'g your internal d/d

 

I do have this item, plus supporting software, if your interested make me an offer

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Fiath, you are indeed wrong about the subject of bit degradation over copies, at least copies made using the normal means of transferring through RAM. The reason is that while the bit as stored on disk is analogue, the bit while stored in RAM is not. If the bit on disk is strong enough to be read as a 1, a 'perfect' 1 gets placed digitally in RAM, with absolutely no memory of how strong or weak the mag flux was on the source disk bit position, other than that it was sufficiently strong to be interpreted as a 1 in the first place. This perfect bit is then transferred to the destination disk, where it becomes re-expressed as an analog mag flux. While the bit as stored on the destination may or may not be perfectly laid down, its condition in *no* way is dependent on the original source bit.

 

Now, if you are using some kind of direct magnetic transferral, ie source mag flux to a signal strength on a wire to a desitnation mag flux, then yes, thats a perfect analog of copying a magnetic tape and it will degrade across multiple copies. But, as far as I am aware, this copy method is pretty unusual and would take special hardware. Standard copies of disk to disk that do transfers through a digital media such as RAM do *not* degrade. If you can offer any proof that they do, I know of an entire industry and scientific establishment that will be quite interested.

Edited by danwinslow
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you'd be better off (if you have an ST/e) is to get the happy discovery cartridge) this is basically the ST version of the famous Atari 8bit disk drive upgrade, the only difference is the ST version is self contained in a cartridge which means

 

The Discovery Cartridge has almost no relation to the Happy 1050 (or 810) enhancements. The same company produced them all, and, if you want, they have the same purpose (copy copy-protected disks).

 

But that’s all they have in common. They are technically completely different. The Discovery Cartridge is far much more powerful. Up to now I consider it to be, by far, the best hardware copier ever made for a personal computer. The newer version of the Catweasel (MK4), a PCI card, will probably match it or at least come very close. Hey, but the DC was produced ~18 years ago !

 

Edit: MK5 was a typo. Corrected to MK4

Edited by ijor
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Fiath, you are indeed wrong about the subject of bit degradation over copies, at least copies made using the normal means of transferring through RAM. ...

 

But, as far as I am aware, this copy method is pretty unusual and would take special hardware.

 

That’s precisely the point. Analog copiers do NOT transfer any data to RAM. And that’s why they are called “analog copiers”.

 

It might be unusual or not, but that’s what we were talking about here, about the degradation of copies made with an analog copier.

 

And no, an analog copier doesn't work exactly as you describe. It is not an analog copy at the voltage/flux level. The signal is digital TTL, otherwise you'd indeed require a very specialized equipment. It is analog at the waveform level.

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