I expanded a NES rom to allow an extra feature (requiring around x9000 bytes of mostly data). Others are looking to put that feature on their own roms but I don't know of a patching system that would work here. At the moment, I'm just telling them what to change by hand.
What is required is to be able to make a normal IPS patch but have it change the data from x3C010-x6000F (fixed bank and tile data on their rom) at x7C010-xA000F on the new expanded rom and leave the new expanded area untouched. Is there any patching system that can handle this?
Thanks