SNES gamepad to GameCube using Arduino Nanon ATMEGA328P

Projects General Guidance
1

Hello everyone! I'm trying to create an adapter that would allow me to plug a SNES gamepad to a Gamecube/Wii port. So far, I've flashed the Arduino with a specific .hex file (created by others) with AVRDUDE. Now it's time to solder the various points, but i'm unsure how to proceed, i'm supposed to first check the inputs with a multimeter, but i'm a total noob with this. Anyone can tell me what the next steps would be ? Thanks.

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Gamecube cable to be connects to the Arduino, then another SNES cable should be also connected.

2

Did these "others" say that a Nano could be used? Or did they say that a Leonardo, Micro or Pro Micro should be used?

3

Yes the project has been done successfully by others:

But not one tutorial shows the entire thing, and i'm a total newbie in this. Here's the diagram:

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