Hello to everyone.
I'm trying to hack some lines of jEnesisDS emulator in order to swap screens. I found a line where there's a function that is called just after rom load, and I replaced a line with a branch to another memory address where I put new code (and after execute it, I return to following line after forced branch).
The problem is where to jump, if I go to address 0x160 (rom header) or if jump to rom near end (to take advantage of some lines with zeros and not destroy original code) the program freezes in a real hardware.
However, if I do a little jump (20-30 lines ahead), it works perfectly, but I'm overwriting code. So I ask: is there a problem with long jumps, or is there a "branch protection" that avoid users hack NDS files?
I hope have explained correctly, and thanks for your time

You adapt the asm patch template for NSMB to insert code into your ROM. It pushes back the main heap by the amount of custom code you add.
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