hi, ①befor you connect the controller,please check the "System Setting", The "Pro Controller Wired Communication" must be enabled before pairing,
Mean that:"Pro Controller Wired Communication" shown:On
②After enabled the “Pro Controller Wired Communication" .
you can connect the controller and receiver
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How to pair up (applies to both Switch and N64):
1. Press "Reset" button on the controller, a red led starts flashing
2. Plug the receiver into the devices, a red led starts flashing
3. Press "SYNC" button on receiver, the led gets fast-blinking
4.Press the"Start" button to pair automatically (the LED is always on after the pairing succesfully)
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Finally, if all the above operations have been completed and the Controller cannot be successfully connected,Please connect the computer upgrade controller.
The following "Link" has the 'N64 wireless controller upgrade package and upgrade tool', which contains tutorials to guide any upgrades.
"Link":https://drive.google.com/file/d/1zkpIliyHJwpgIZ6sKm71I0fuKMibkPsp/view?usp=sharing