Re: Module 6 (was Re: CiderPress v2.1.0 released)

[mjmahon@aol.com (Michael J. Mahon)]

Andy McFadden wrote:

<snip very interesting anatomy of a cassette program!>

>Looks like they crammed more than one program into a package and simply
>changed the start address in the part in the beginning.

When you noted that all of page 1 was loaded with 03 03, that
answered my question of how they knew the stack pointer--
they didn't!  Clever brute force hack to force a transfer of control.

This cassette is an unusual display of trickiness for so little
effect.  Requiring multiple programs to load correctly (and slowly)
to run one of them is a dubious ease-of-use tradeoff.

This prefigures the coming "copy protection wars".

Or maybe the programmer was just showing off.  ;-)

-michael

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