[HN Gopher] PC Floppy Copy Protection: Softguard Superlok
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PC Floppy Copy Protection: Softguard Superlok
Author : anyfoo
Score : 85 points
Date : 2024-09-05 23:19 UTC (2 days ago)
(HTM) web link (martypc.blogspot.com)
(TXT) w3m dump (martypc.blogspot.com)
| jmillikin wrote:
| Previous article in the series:
| https://news.ycombinator.com/item?id=41346124
| progbits wrote:
| That's for different protection scheme. But also a great read!
| jmillikin wrote:
| Oh wow, I wasn't expecting two floppy disk copy protection
| articles in one week. Thanks for the correction!
| progbits wrote:
| Another great article from the same author that I found
| when browsing their blog after the previous article:
|
| https://martypc.blogspot.com/2023/06/hardware-validating-
| emu...
|
| Probably should be a separate HN submission at some point.
| rav wrote:
| I thought this was going to be about the physical notch switch on
| some floppies to switch them between read-write and read-only
| modes... That thought alone brought back some deep childhood
| memories!
| user3939382 wrote:
| The trick was to line up the write-protected one with one that
| already had the notch.
| codazoda wrote:
| That reminded me of a couple "hacks" we did back then...
|
| 1. Cover the write protect notch on a 5 1/4" floppy with a
| sticker to enable writing.
|
| 2. Melt an extra hole in a 3.5" floppy with a cheap soldering
| iron to double its capacity to the 1.44MB that later became the
| standard.
| andrewshadura wrote:
| In 51/4" disks, the uncovered notch meant R/W while stickers
| were used to prevent writing.
| amenghra wrote:
| I think we used to punch holes in 51/4 floppies to enable
| writing to their backside?
| medmunds wrote:
| Yep. An ordinary round hole punch worked, but you could
| also get a purpose built punch that made a nice
| rectangular notch, had a guide to get the position just
| right, and had more leverage making it easier to punch
| through the thick jacket. "Dual sided" floppies (with two
| factory cut notches) cost enough extra that the tool paid
| for itself pretty quickly, IIRC.
|
| Of course, the floppy manufacturers warned that the
| cheaper single sided floppies had only been tested on the
| front side, and might have defects on the back. But I
| don't remember that ever being a real problem.
| wileydragonfly wrote:
| We used a drill for #2 but the price difference disappeared
| pretty quickly iirc
| tamimio wrote:
| Yeah and when you put some tape on it and now you can write..
| it felt like neo in the matrix!
| BillLumbergh wrote:
| Don't copy that floppy
| OnlyMortal wrote:
| I used to crack C64 disk games. They were mostly trivial because
| I wrote a disk sector editor that would disassemble blocks on
| demand.
|
| One that comes to mind were Ocean's copy protection that was
| hacked by a load of 1 into the accumulator and a return. They had
| a "bool IsValidDisk()" type of routine.
|
| After cracking one of their games I could crack others in less
| than 2 minutes directly on a copied floppy.
| peterfirefly wrote:
| Perhaps this is a good place to ask if anyone has a copy of the
| manual for CopyWrite by Quaid Software?
|
| The manual had a really good description of the floppy controller
| interface + various tricks one could use to copy protect
| floppies.
|
| I know where to find several versions of the program. I am not
| interested in those. I am only interested in the manual.
| jakobdabo wrote:
| I found two versions at https://archive.org, there's a PDF
| manual too.
| peterfirefly wrote:
| You are right, there is a a copy with a manual now! It was
| uploaded 4 months ago and it sure wasn't there all the
| previous times I've looked.
|
| Unfortunately, the manual doesn't quite match my memories. I
| recognize a lot of the text and layout so it is clearly
| something I have seen before, but the technical info isn't
| really there.
|
| This manual is from May 1989. I read the manual a bit before
| that, perhaps in 1987, perhaps 1988.
|
| So, does my memory play tricks on me or did they remove all
| that lovely tech info? All there's left in this version is
| Chapter 12 "Technical Terms" (which I recognize as something
| I have read a version of before).
|
| I know I have read about using track reads to catch some of
| the copy protection tricks (like in the two MartyPC blog
| posts) and track writes (occasionally even track writes that
| are aborted at just the right time) to force the data on disk
| to be just the right kind of wrong.
|
| I double checked that it wasn't in the Copy II PC manuals I
| could find: the V6 manual from 1990 and the Copy II PC Option
| Board manual.
| codazoda wrote:
| It's not super related but all the talk about how easy the Sierra
| games were to crack reminded me of that time I built a crack for
| nearly all shareware of the era.
|
| https://joeldare.com/that-time-i-built-a-crack-for-nearly-al...
| accrual wrote:
| Finding your own software bundled or integrated with someone
| else's software (assuming those are the terms one desired)
| would be one of the ultimate feelings of flattery to me.
| mannyv wrote:
| I remember one trick was to burn a hole in the disk at a specific
| track/sector location then try to read it. If you got an I/O
| error then the disk was real.
| snozolli wrote:
| That brought back memories of playing off a backup and having to
| switch to the original for validation, and of some Amiga program
| that claimed to copy copy-protected disks. It thrashed the floppy
| drive like crazy and looked very, uh, sophisticated (as in lots
| of virtual indicator lights blinking away on-screen), but I was
| never convinced that it actually worked.
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