Wakachamo: I think the only situations where we disagree are in matters of speculation, so let's not turn this into a needless fight.
What I can't understand is that you still put yourself through reading this thread even though you didn't want to.
I didn't. I read the first page.
When did I say there were any restrictions, software-wise? Plus, Different-languaged games are compatible over local wireless.
Plus, you have to stop thinking that language = region. They're two completely different things.
For the first "software," I was speaking of the DS firmware. Sorry if that wasn't clear. From what I've been following in the DS homebrew community, there's no functional difference between DSes from different regions, hardware or firmware.
And do note that I'm basing this off just pure logic, since I can't confirm this. (yet, btw) This also has a bit of personal experience. When I talk about that "experience", it's when something weird happened to me. I tried to play against my friend. I had a US Metroid Demo, and he had a UK one. Since I knew at that time that DS software was in no way region-restricted, it must've been because of the DS. My DS was American, and his was European. So, even though this might contradict many people on the fact that the DS isn't actually hardware-locked (which I'm almost sure is true, like you said in your post), I think it's still possible that NoE might screw with things every once in a while. However, don't get offended with what I say, since I can't confirm this. I'm still, as of now, basing this off logic and basing it off of this little happening as well. Nonetheless I will try to confirm this ASAP when D/P comes out here.
Judging by that, I'd guess that the Metroid Prime Demos are different between the US and UK, not the DSes. Games from different regions are sometimes byte-per-byte identical, but at other times, they can vary completely, even in communications protocols.
Demos, even more than finished games, would tend to be different between releases because they're unfinished. Maybe Retro Studios decided to change the MPH communications protocols after the US demo release but before the UK one?
Of course that works. Why? Because it's probable that you both have a DS bought in the US. Plus in this thread, I'm not talking about JP-US differences. I'm talking about US-EUR differences. You might've not realized that NoE does make a lot of changes in games very often.
You're right in that it doesn't provide any info as to the existence of a hardware incompatibility. The point I was trying to make is that different-regioned and/or different-languaged games are
often compatible with each other. We probably both agree on this, but I couldn't tell at the time.
Tell me how they're much more complicated in their communications. In fact, it should be the opposite. Do note that Mario Kart DS has to request the player's coordenates all the time, and D/P doesn't even need to do something close to that.
I was speaking only of language-specific communications. Kart coordinates and such are no different in Japanese. Pokémon nicknames are different between languages, however. (The English/French/German/Italian/... names use 1 byte per character @ 10 characters, while the Japanese names use 2 bytes per character @ 5 characters.)
English D/P and Jap D/P work fine. 1Up confirmed this. And please take note that playing over the net is very different when comparing to local wireless. That's a big mistake, since the two don't work the same way. (One's actually connecting to a network, the other's communication via ad-hoc)
All I was saying is that the string formatting hurdle had already been overcome, demonstrated by the third-gen interoperability (which I've experienced) and the internet interoperability. It follows that the local ad-hoc ought to work as well, which you say it does.
I think it does. The base of the connection is handled by the DS itself, I believe. I can't confirm this nonetheless, but I will be able to as soon as D/P comes out here in Europe.
From what I've been following in the homebrew community, this is not true. All but the lowest layers are handled entirely by the game. These lowest layers are the same regardless of where your DS is from.
Language barriers don't exist on DS and Wii games.
Not on their own, but the D/Ps from different regions (or at least those of different languages) have different programming. (Particularly the offsets of various data structures in the save file.) Japanese PBR may not know how to handle a US D/P. Someone ought to test, but I'd guess that Japanese PBR can't link with US D/P.