Reports from Japanese gamers and importers are that the Nintendo DSi blocks R4 Cartridges. There are also rumors that it burns a “P” into the forearms of anyone who is found using them, marking them as a "Pirate" for the East India Trading Company.

Apparently they flat out don’t work, putting them in does nothing, and there’s no workaround as of yet. This doesn’t mean there isn’t going to be one, since pirates never sleep, but Nintendo is apparently making leaps towards eliminating the piracy threat that has lowered Nintendo DS game sales for some time. Trying to eliminate shovelware, on the other hand, isn’t on the agenda.

I can’t say I can blame them, if nothing else it will make it so pirates need to spend MORE money trying to save money on game sales. It's also region encoded, which sucks for importers.Like I said, it's only a matter of time before this is cracked soon, the only question is whether or not it will need an entirely new cart. Not that this matters to any of you, I’m sure no one here would stoop so low as to resort to piracy. 

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