While they do function to some extent (80% compatibility or so I'd guess like most clones), really what they are, are consoles on a chip that highjack the other consoles power and controls - you connect the "cart" to the tv.
No, you plug the cartridge in to the SNES to get power then the video signal goes from the cartridge to the TV. It's just a clone console on a chip. Nothing special really.
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