Where is DS region lock stored?

[rednblu]

Im in the planning phase for repairing my Pokemon black 2 cartridge, the main idea is to find a cheaper Japanese copy, then solder the original flash and ROL chip back on to see if it works.

(I think I have one other chip that kind of survived, but the resistors and IR sensor are not in good shape)

I've heard from some sources that problems arise when playing DS games from other regions on the 3DS

Is there any specific part of the cart that carries region information?

Thank you!

 

[4d1xlaan]

the last digit of game code does it

or rather, the console checks that last digit of the game code in rom, and it doesn't let you play it if it's not one of the allowed ones for your region

english gen 5 pokémon games are region-free, for the record

 

[IC_]

What are the problems you heard of?
The DS and its games have regions, but there is no region-lock and thus they are region-free.
The 3DS and its games have region-locking, but in backwards compatibility with the DS, the 3DS will play DS games from any region.
I just confirmed this with an European DS game on an unmodded Japanese 2DS.
-------
Post below me explained.

 

[The Real Jdbye]

the last digit of game code does it

or rather, the console checks that last digit of the game code in rom, and it doesn't let you play it if it's not one of the allowed ones for your region

english gen 5 pokémon games are region-free, for the record

DSi enhanced titles (which Pokemon B/W happen to be) are region locked. They have to be forced to run in DS mode which requires a hacked console, at that point you are region free anyway.

 

[rednblu]

You guys are amazing, thank you so much!!