Bliss-Box - 4-Play - One Adapter for Many Controllers
PR.com (press release)
For example the SNES Y, B, X, and a are mapped like the Neo Geo A, B, C, and D so that when you switch from one to the next you use the controller in the same manner. Both left most buttons (SNES:Y or Neo Geo:A) are mapped to the emulator the same.



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