Finally プチコン3号 (Puchikon 3 [san] gou) has currently only been released in Japan, but SmileBoom is trying to release this in North America and Europe sometime in 2015 (hopefully.)
I'm just clearing up the confusion.
プチコン (Puchikon) was only released in Japan. This version didn't have BGM, (I think) and didn't have the QR Code scanning function. You had to program it to have it.
プチコンmkII (Puchikon mkII, known in North America as Petit Computer) was released in Japan and North America this included BGM and the QR Code scanning function.
It's pretty cool getting information on a game I'm hoping will come soon to both North America and Europe very soon. I'll use both Miiverse and the Matome Petitcom 3D wiki for some games already made! Easier than waiting for games on an American wiki!