[atari7800] Re: Question about encryption area

> > It was originally done this way to allow for bank switching carts,
> > but was also sometimes done to allow the ROM to be modified after it was
> > digitally signed.
>
> ...doesn't that sort of defeat the purpose of the signature?

Yes and no.  The purpose of the signature was twofold: provide a way for the
7800 BIOS to determine if it needed to be in 7800 or 2600, and to provide
Atari a way to control who made games for the 7800.  So as long as there was
a signature of some sort then both requirements were solved.

However, in some cases these minimally signed games could be used to
sidestep the signature process when creating a new game.  (As documented by
Eckhard Stolberg at http://home.arcor.de/estolberg/texts/backdoor.das )
This workaround is no longer required to create homebrews since we now have
the tools to create the digital signature.

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