WiiLi.org

[volsung]

With the basics of the acceleration sensor under control, it looks like the next big thing to figure out is the IR sensor.

What we know so far:
* The accelerometer only returns data after being turned on.
* You can pick which channel it goes to, and not all channels have the same payload size.
* No IR data is reported if you do nothing.

Plausible guesses from various people in the forum:
* Like the accelerometer, IR position information probably needs to be activated when required.
* It may function in a similar way to the accelerometer, with a host supplied channel number.
* To receive the information, you probably need to pick a channel number with a larger payload, since there certainly isn't room in the 5 bytes on channel 0x31.

Possibly related mysteries:
* Why does selecting channel 0x3e or 0x3f cause accelerometer reports to alternate channels?
* What are the mysteriously changing first two bytes of the accelerometer reports? I briefly thought they might be IR data, but 2 bytes isn't nearly enough room to record the x-y positions of two points with any useable accuracy. What is it really?


I've tried sending random stuff to channel 0x12 to see if I can maybe turn on motion sensing and IR, but no luck so far, and there are no other channels with convenient 2 byte payloads. Next step I suppose is systematically trying all 256 values for that first byte to see if a combination of bits is needed to get IR sensor reports.

[volsung]

Wow, I guess I should hit reload on the wiki before posting. Several people are going nuts in there adding new information about the IR sensor, the speaker, and the memory. I hope they find the forum so I can ask how they figured all that out.

[RandomInsano]

So I got to mess around with the Wii some more tonight (friend brought it over), and we tried using candles for a sensor bar. No surprise that it worked.

Too see if the Wii could track more than two IR sources (if you go into sensitivity calibration or somesuch you'll noticed the two points), we lit up a few candles in addition to having the sensor bar plugged in, and the Wiimote can track up to four locations, but not a fifth. After lighting up the last candle, the fourth dot bounced from sensor bar to candle and back again.

Not sure if it's USEFUL information, but sort of neat in any case.