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It appears that the 32 bytes from 0x(4)a60020 are, as usual, calibration information, but it is unknown how they work.   
 
It appears that the 32 bytes from 0x(4)a60020 are, as usual, calibration information, but it is unknown how they work.   
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The 128 bytes from 0x(4)a60050 - 0x(4)a600cf change briefly, but seemingly randomly, after the extension is initialized.
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The 128 bytes from 0x(4)a60050 - 0x(4)a600cf change briefly, but seemingly randomly, after the extension is initialized. More examples of this data block changing over time can be found here: [https://docs.google.com/Doc?id=dds4pks_606fmcd6zwt&hl=en Three Data Samples from Wii Motion Plus (Google Doc)]
    
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.
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