Subject: Re: [stella] The mother of all bankswitching trickery :-) From: Manuel Polik <cybergoth@xxxxxxxx> Date: Sat, 07 Dec 2002 18:11:35 +0100 |
Hi Paul! >Cool. So I guess they just modify the JMP address each time to call >different subroutines in the upper bank? How do they get back? Same way? I Have to analyze that further... > It's clever, but I sure can't see wasting 6 bytes of > RAM for bankswitching! It's strange, yes. I thought it was probably to prevent reverse-engineering? I found yet another oddity speaking for that theory: The second bank starts like this: ; Second bank ORG $2000 RORG $F000 START2: LDA $FFF8 ;4 JMP $BC96 ;3 See? That jump is heading towards nirvana! And I think *just* tweaking the pointer wouldn't even save any ROM in exchange for sacrificing them 6 bytes of RAM... Greetings, Manuel ---------------------------------------------------------------------------------------------- Archives (includes files) at http://www.biglist.com/lists/stella/archives/ Unsub & more at http://www.biglist.com/lists/stella/
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