Re: EDD + CARD

[Stephen Shaw <bottrawler@junkbuster.zzn.com>]

On Fri, 26 Jul 2002 17:18:42 GMT, Dick Sisco wrote:

> On Fri, 26 Jul 2002 15:33:17 -0000, russotto@grace.speakeasy.net
> (Matthew Russotto) wrote:
>
>>In article <md61ku4rts0okshsusisv15ifgeeuv9g2r@4ax.com>,
>>Dick Sisco  <dsisco11111@mchsi.com> wrote:
>>>
>>>But that is exactly why it works as a protection scheme.  After about
>>>8-10 0 bits the standard Apple (or IBM) controller begins returning
>>>random bits.
>>
>>Why does it do that?  A 0-bit is a lack of transition on the disk; while
>>the controller may not be able to figure out how many non-transitions
>>occurred, I don't see why it should start returning 1s.
>
> As it was explained to me, the circuitry in the disk controller turns
> up its aplification(?) if it doesn't see transitions. It eventually
> senses a transition when there really isn't one.   I can't swear that
> that's an accurate description, but that was the way the instructor at
> a disk duplicaton seminar explained it to me.  And it did seem to
> work.

Ok. if the above is the case then it is quite easy to back door into the data
stream with an RS232 converter to a PC/Mac/Linux box and read the binary data,
sort out what copy protection is being used and nullify it.


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