That's fair. I had been assuming you'd use ITCM for tight loops regardless but I can't recall whether you can do that on GBA now that I think of it. As for cop

That's fair. I had been assuming you'd use ITCM for tight loops regardless but I can't recall whether you can do that on GBA now that I think of it. As for copying data around, yeah, if your emu can't copy data to/from VRAM in a sensible manner it's just not going to work out.