Comment by TuxSH
8 hours ago
The DS, more specifically the arm946e-s has an MPU, not a MMU (you're confusing it with the 3DS's Arm11). Not like it makes much of a difference anyway, you configure either once or twice then leave them be.
Honestly, I think why the GBA is more popular than the DS for that kind of thing is because it only has one screen (much less awkward to emulate), has high-quality emulators that are mostly free of bugs (mGBA most notably), and its aspect ratio is better than the DS anyway (3:2 upscales really well on 16:10 devices). That is to say, it's much easier to emulate GBA software on a phone or a Steam Deck than it is to emulate DS software.
gah, you're right, I was thinking of memory protection (as in, marking the relevant regions as read-write and read-execute) when I wrote MMU.
It's of course optional, and you can ignore it for trivial examples, but most games and SDKs will tweak it all the time when loading additional code modules from the cartridge.
It's just another way in which the DS is more complex to use properly without an SDK to do this for you - there's just more to think about. At least compared to how the GBA lacks all of this and the entire cartridge is mapped into memory at all times.