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DS Misc > Patch slot 2 cartridge on boot from slot 1?

#145683 - npo - Tue Nov 20, 2007 12:19 pm

Hi guys,

I'm wondering whether it is possible (or if a solution already exists) to patch an original cartridge in slot 2 on the fly when booting from slot 1.

To clarify, is it possible to:

- Load an app (existing or yet to be developed) using your slot 1 method of choice
- In the app, specify a patch file to apply
- The app then boots an original catridge in slot 2, applying the selected patch to memory.

Specifically, I am interested in applying the Mother 3 menu patch (http://mother3.fobby.net/) to my Japaneses Mother 3 cartridge while I play it on the DS, however I think that others might find uses for such a capability as well.

I did a quick search but didn't find anything on this. It's entirely possible that I didn't choose the right search terms, however.

#145688 - tepples - Tue Nov 20, 2007 1:11 pm

This is not possible. Unless you can intercept reads or writes from ROM, you can patch only the program's initial RAM state. Without external hardware, you cannot intercept reads or writes from GBA ROM, and programs clear out RAM when they start.
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