#1182 - coca77 - Wed Jan 15, 2003 4:27 pm
How do selectable game trainers work exactly. You cant write to the code obviously (as its in rom), so do they set up an interrupt that continusly changes some value in ram?
#1190 - Touchstone - Wed Jan 15, 2003 5:14 pm
From what I've heard you _can_ write to ROM on the flash cartridges available. It's helluva slow but it's possible and given that all trainers are run from flash cart. or emulator maybe that is how they do? Wild speculations from my side. :)
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#1198 - Splam - Wed Jan 15, 2003 6:02 pm
More wild speculation ;)
You could replace a b instruction in the file, and make it jump through your code (presumes theres going to be a few bytes of ram free somewhere) then branch to where the original b instruction was going. Obviously the variables are held in ram so your little routine just changes those (lives variable constantly having a value stored into it etc). Seen this method used on cart based stuff before so I reckon it might be something like that. :)
#1207 - Touchstone - Wed Jan 15, 2003 6:41 pm
Your method sounds a bit more reliable Splam. Interesting stuff.
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