Changes

= Wii Motion Plus =

= Wii Motion Plus =

The Wii Motion Plus extension is unusual in that it has its own extension port on the back allowing a Nunchuk for example to be plugged in along with the Wii Motion Plus. That might radically change the way it is detected and used compared to other extensions.

The Wii Motion Plus is at register 0xA60000 instead of register 0xA40000, because it has its own extension port on the back allowing a Nunchuk for example to be plugged in along with the Wii Motion Plus.  

 

Games attempt to detect the Wii Motion Plus by trying to read the two-byte expansion identifier at 0xA600FE. It is unknown what value the Wii Motion Plus returns for expansion type. If a Wii Motion Plus is not detected then the attempt to read those bytes will fail.

The Wii Motion Plus consists of two rate-gyros. These gyros measure rotation SPEED, but can't actually measure absolute orientation, which causes drift if not corrected by some other data source. Speed is one step better than the acceleration reported by the accelerometers. One of the two gyros will obviously have to measure yaw, since that can't be measured by accelerometers. The other axis is unknown, but I would guess pitch. Unlike the rotation measured by accelerometers, whose axes are defined by gravity, the gyro axes are relative to the angle of the Wiimote. So even if it can measure yaw when the Wiimote is in the normal orientation, it won't be able to detect yaw when the Wiimote is vertical.

The Wii Motion Plus consists of two rate-gyros. These gyros measure rotation SPEED, but can't actually measure absolute orientation, which causes drift if not corrected by some other data source. Speed is one step better than the acceleration reported by the accelerometers. One of the two gyros will obviously have to measure yaw, since that can't be measured by accelerometers. The other axis is unknown, but I would guess pitch. Unlike the rotation measured by accelerometers, whose axes are defined by gravity, the gyro axes are relative to the angle of the Wiimote. So even if it can measure yaw when the Wiimote is in the normal orientation, it won't be able to detect yaw when the Wiimote is vertical.

In addition to providing yaw, the gyros also allow the software to tell the difference between orientation and acceleration, which are difficult to tell apart from the accelerometers which measure a mixture of both.

In addition to providing yaw, the gyros also allow the software to tell the difference between orientation and acceleration, which are difficult to tell apart from the accelerometers which measure a mixture of both.

Wii Motion Plus will be released between June 8 and June 12, depending on the region. More information will be available then.

Wii Motion Plus will be released between June 8 and June 12, depending on the region. More information will be available on June 11.

[http://www.ailive.net/lm2.html Wii Motion Plus Documentation at AiLive]

[http://www.ailive.net/lm2.html Wii Motion Plus Documentation at AiLive]

[[Category:Hardware]]

[[Category:Hardware]]