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The cleverest floppy disc protection ever? Western Security Ltd

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Re: The cleverest floppy disc protection ever? Western Security Ltd

#51

Post by jedberg »

FpUser wrote: post #45
jedberg wrote: post #20

My favorite copy protection was on some games I had (I want to say they were Microprose games? But I could be wrong) where they would cut the hole in the disk just slightly bigger, and then take advantage of the fact that in DOS you could talk directly to the hardware to convince the read head to go just a little too far. Then it could read the magic 41st track to load the game, but no disk copy program could copy it…

Nah. I remember those days. Programs that could read/write/discover more tracks than the standard amount were widely available.

Well, it was 30 plus years ago, but what I remember is that at first it was just the games that were doing it, and then people figured it out and made those other programs, making the copy protection useless.

Re: The cleverest floppy disc protection ever? Western Security Ltd

#52

Post by dunham »

Firehawke wrote: post #8
h2odragon wrote: post #2

I never did BBC Micro, but in the early PC days there were "Copy II PC" add in ISA cards that the floppy cable passed through on the way to the drive. With their software most any floppy disk could be copied with a standard PC drive; and with a bit of hacking you could do things like read Victor 9000 floppies. There was only one floppy I could never get, a licensed Scrabble game that insisted on writing scores to its…

The "Copy II PC Option Board", yeah. I knew a guy who had one, and it definitely could handle a lot of stuff that you normally couldn't. Interestingly, you really wanted an early-era board because they were forced to water down the later revisions so they couldn't copy newer protection schemes.

My fuzzy recollection is that the option board could read the entire track at once, raw - not MFM decoded, where the typical controller in a PC had a high level interface that only gave you sectors.

One copy protection system that I remember was a track that had a mix of long and short sectors with the short sectors embedded in the middle of the longer ones. (Sectors header/footers were marked by special bytes that were illegal MFM coding.) If a program tried to copy the the track with a normal floppy controller, they would have more sectors than would fit on a track.

Re: The cleverest floppy disc protection ever? Western Security Ltd

#53

Post by marzell »

FpUser wrote: post #45
jedberg wrote: post #20

My favorite copy protection was on some games I had (I want to say they were Microprose games? But I could be wrong) where they would cut the hole in the disk just slightly bigger, and then take advantage of the fact that in DOS you could talk directly to the hardware to convince the read head to go just a little too far. Then it could read the magic 41st track to load the game, but no disk copy program could copy it…

Nah. I remember those days. Programs that could read/write/discover more tracks than the standard amount were widely available.

There was a similar situation with CDs where you could overprovision data that existed past the technical limit of useable range. I think that's was utilized in NINs Year Zero ARG experiment.

Re: The cleverest floppy disc protection ever? Western Security Ltd

#54

Post by DrBazza »

I seem to remember the only software that would copy any disk you pointed it at, was in fact the source code listed in the official Acorn DFS manual. With the drawback that it copied one sector at a time, so without a double drive, that was a lot of swapping for a 40 track disk, let alone an 80 track one.

Re: The cleverest floppy disc protection ever? Western Security Ltd

#55

Post by dirkt »

jedberg wrote: post #20

My favorite copy protection was on some games I had (I want to say they were Microprose games? But I could be wrong) where they would cut the hole in the disk just slightly bigger, and then take advantage of the fact that in DOS you could talk directly to the hardware to convince the read head to go just a little too far. Then it could read the magic 41st track to load the game, but no disk copy program could copy it…

My favorite one is the spiral tracks on the Apple II, which were possible because all phases of the stepper motor were directly accessible on the controller, so you could move the stepper motor in quarter tracks.

Impossible to copy unless you reproduce the head movements at the right time.

Re: The cleverest floppy disc protection ever? Western Security Ltd

#56

Post by Zardoz84 »

MisterTea wrote: post #31
carapace wrote: post #5

Who recalls the provenance of this old legend about the fellow who challenged his pal to decode a certain floppy? It was a bog-standard DOS boot disk (IIRC) that he could put in his machine and boot normally. But his pal put it in his computer and... nothing doing, no boot. Analysis of the floppy availed not. The challenge went unmet. What did our hero do to make the floppy? .esrever ni nups evird eht os ytiralop eti…

This reminds me of a less interesting story: My father bought a 386 for his work to replace a 286 which only had a 5.25 floppy drive. The 386 had both a 3.5 and 5.25 floppy drive so he quickly switched to the more sturdy 3.5 disks and moved a lot of work to the 3.5's. Everything was working great until he got a second similarly spec'd 386. For some reason the machines couldn't read each others 3.5" disks. So he calle…

This remembered me when I had a ZX Spectrum +3 as child. At some point, a belt broken and my father replaced with a different belt. So, it can't read anymore my old floppies. I can only use the floppies if I formatted again.

Re: The cleverest floppy disc protection ever? Western Security Ltd

#58

Post by m463 »

Back in the 1980's I think there were a lot of interesting schemes.

The solution was to just get an updated version of copy2pc or copywrite and they would have a fix.

But I remember a few schemes that were interesting workarounds.

One was the hole in the disk, one was a laser-burned dot on the disk.

I recall with the hole in the disk - the software would try to read and if it succeeded it was a copy.

The second one was slightly different and I believe the software would write to it, and read it back, and if it could read it back it was a copy.

However the best of all was either the scratch-n-sniff card from Leather Godesses of Phobos, or the Age Verification of Leisure Suit Larry.

example:

  "Gone With The Wind" is about
  a. outer space.
  b. a bank robbery.
  c. four hours long.
  d. dust.
or

  President Ford prescribed _____ for dealing with economic problems.
  a. tranquilizers
  b. employment
  c. that everyone wear a WIN button
  d. that everyone should have a nice day

Re: The cleverest floppy disc protection ever? Western Security Ltd

#59

Post by mattbee »

The other thing this scheme gives you is a unique image per customer, so you could use it to trace illegal copies.

When I worked on some expensive emulator software 22 years ago, floppy protection wasn't appropriate but I suggested to the boss that we use the order of linker symbols in the main executable to encode the customer's serial number.

I guess it was a No because they wanted to use a standard duplicator, but also piracy was pretty well deterred by the 486 daughter board you needed to run it :)

Re: The cleverest floppy disc protection ever? Western Security Ltd

#60

Post by Doctor_Fegg »

afandian wrote: post #32
berkut wrote: post #18

Slightly off-topic, but since when were floppies referred to as "disc", as opposed to "disk"? I thought it was from Diskette? Is it a language / region thing? Optical discs were "disc", but at least growing up in the UK in the 80s/90s with DOS/Windows, I'm pretty certain I remember them always being "disk" for floppies? Am I misremembering?

The 'k' spelling is American. Look at the ports on the BBC and you'll find British spellings of 'analogue', 'disc'. https://oldcomputers.net/bbc-micro.html The User manual contains more language. For example, 'program' for computer program (vs 'programme' which would be used for TV) http://bbc.nvg.org/doc/BBCUserGuide-1.00.pdf

The Amstrad CPC was "disc" too, reputedly because the first mouldings used it by mistake and Amstrad was too cheap to ever correct their error.
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