Wii Remote pair pin code

Bluetooth Pairing
The wiimote supports the legacy bluetooth pairing methods. This involves sending a PIN to the wiimote. Bluetooth pairing is not required to use a wiimote and you can proceed by establishing a HID connection without pairing at all. However, if the wiimote is paired, it will actively seek out for its last connected host on disconnection and reestablish the connection. The following section explains the bluetooth device pairing, if no pairing is required, skip this section.
Bluetooth pairing must be initiated by the host by sending a "Require Authentication" HCI command to its bluetooth device. The bluetooth device will ask the host for a link key, which must be rejected so it will ask for a PIN-Code. The PIN-Code is the binary bluetooth address of the wiimote backwards. Following a short piece of C code to calculate the PIN:
Lets assume the Wiimote has the bluetooth address "00:1E:35:3B:7E:6D". If you want the PIN for bluetooth pairing in a simple string, do the following:char pin[6];pin[0] = 0x6D;pin[1] = 0x7E;pin[2] = 0x3B;pin[3] = 0x35;pin[4] = 0x1E;pin[5] = 0x00;Now "pin" contains your bluetooth pin that should be used for pairing your devices.If connecting by holding down the 1+2 buttons, the PIN is the bluetooth address of the wiimote backwards, if connecting by pressing the "sync" button on the back of the wiimote, then the PIN is the bluetooth address of the host backwards.
After sending the PIN to the bluetooth device via HCI commands, the wiimote will return a "Authentication Accepted" command and the pairing is established (both devices are bonded now). After pairing you continue with establishing the HID connection the same way as without pairing.
If the host successfully bonded with the wiimote and established an HID connection the wiimote will save the bluetooth address of the host and enable single press reconnection. That means if the wiimote is now disconnected from the host, it will actively seek out for the host if any button is pressed and establish a baseband and HID connection. The wiimote will never actively send pairing requests since this is not needed. Also remember that this works with any button not only the power-button. However, after establishing the connection, the wiimote sends a button-input-report and this allows the host to see what button was pressed. So the host may reject the new connection if any button except the power-button was pressed.
The new bluetooth pairing method SSP (Secure Simple Pairing) is not supported. Also it is not yet investigated whether a link key has to be created (by sending a PIN) on every connection or whether the link key can be saved and reused on new connections. Though, creating a new link key on every connection works fine.
The wiimote has space for several host addresses (at least 3 are known to work) so it can be paired with more than one host (like PC or Wii) and it will try in reverse order to reconnect to the hosts. That is, the last paired host is tried first and so one. If button 1 and 2 or the sync button on its back are pressed, the wiimote will not actively seek out for its host but instead place itself in discoverable mode and wait for incoming connections so bluetooth pairing does not conflict with normal host-side connections.
It is not known how to remove the hosts addresses from the wiimote, however, with some investigation it should be possible to locate them in the EEPROM and manipulate them. If this is considered a security issue, then don't pair your devices.