Post subject: TAS binary loader.
Joined: 10/23/2011
Posts: 15
I was just thinking. We have all those TASes that corrupt memory in controlled ways. How hard would it be to corrupt the memory enough to allow a simple binary loader to run and then to bootstrap FORTH or BASIC through the controller or to do some other fun thing like that?
Post subject: Re: TAS binary loader.
Emulator Coder, Skilled player (1141)
Joined: 5/1/2010
Posts: 1217
haslomaslo1 wrote:
How hard would it be to corrupt the memory enough to allow a simple binary loader to run and then to bootstrap FORTH or BASIC through the controller or to do some other fun thing like that?
That would require hijacking program execution flow, and most memory corruption glitches don't allow that. Most systems have write-protected program code. Yes, all systems can execute from some kind of RAM, but you have to make the program jump there somehow. Also, it would be material for playaround videos only (and in games that allow SRAM saving), as the game state is wrecked so bad that the game is uncompletable without resetting.
Joined: 1/5/2012
Posts: 52
Location: Maridia
More difficult than getting the game to jump to SRAM would be getting a useful program there just by button presses... :)
Editor, Emulator Coder, Site Developer
Joined: 5/11/2011
Posts: 1108
Location: Murka
Rena wrote:
More difficult than getting the game to jump to SRAM would be getting a useful program there just by button presses... :)
Super Mario Land 2 glitched TAS writes RAM addresses by out-of-boundsing the play area and then having the RAM appear literally as blocks on the field. Chrono Trigger glitched TAS writes RAM addresses by corrupting the item list to hell. Both of these methods have limitations, but the idea certainly isn't impossible.
Player (12)
Joined: 6/17/2006
Posts: 501
I believe the Famicom Disk System would be a perfect candidate for such a thing because the program data resides on writable memory. The pinnacle of this would be to start playing a specific Famicom Disk System game and somehow abuse a glitch that would allow reprogramming the entire disk so that it becomes an entirely different game. The holy grail: Playing Zelda no Densetsu and transforming it into Super Mario Bros. through input alone! :D