This little pcb is used with the latest firmware for the Blue Retro Bluetooth controller mod for an internal install. This is a DIY build and requires some soldering experience to have a proper build working. The circuit for this pcb was designed by ManCloud89 and it’s purpose is to disable the synced Bluetooth controller on the controller port once a wired controller is plugged in as to not have conflict between the 2.
Below are some very detailed install diagrams by Nostalgic Indulgences who has been so nice for documenting the install and making diagrams, follow him or his github for new installation diagrams as he makes them. https://github.com/nostalgic-indulgences/BlueRetro_Internal_Installation
The PCB has a jumper for 5v consoles that needs to be bridged closed in order to work properly, for 3.3v consoles this is not required and should be left unbridged (open).
Installation Pictures for N64