Wii技術介紹 from (MIT) Technology Review - Switch

(MIT) Technology Review July 2007
http://www.technologyreview.com/

Hack: The Nintendo Wii
Technology Review looks at the inner workings of the Nintendo Wii game
console.

By Daniel Turner

Initially discounted by game-industry watchers as graphically underpowered
compared with the Sony PlayStation 3 and - Microsoft Xbox 360, the Nintendo
Wii has wiped the sales floor with its competitors. In February 2007, 335,000
Wiis were sold in the U.S., versus 228,000 Xbox 360s and 127,000 PS3s. Behind
the Wii's success is its unique controller: simple and wireless, it responds
to your movements in a natural manner, turning into a baseball bat, a sword,
or a hand, as necessary. It is, in a word, fun.

MEMS Sensor 1 (Wii Remote)
The key to the Wii's main controller is its three-axis
microelectromechanical-system (MEMS) accelerome- ters, which measure movement
in three dimensions. Two-dimensional MEMS sensors have been around for a
while, but adding the third axis presented challenges. "You have moving parts
that you have to protect from the environment," says Christophe Lemaire, a
marketing manager at Analog Devices, which makes the sensor used in the Wii
Remote. Most MEMS sensors come in hermetic packages made from ceramics or
metals. But this increases the devices' size and cost--a problem that the
additional sensory dimension was only going to aggravate. "What we do," says
Lemaire, "is put a cap over the sensor elements at the wafer level." That
creates a hermetic cavity and enables the use of a cheap, small, lightweight
case.

Bluetooth
The Wii Remote uses a Broadcom Bluetooth chip to wirelessly send a constant
stream of position, acceleration, and button-state data to the Wii console.
The chip also contains a microprocessor and RAM/ROM memory for managing the
Bluetooth interface and converting voltage data from the accelerometers into
digitized data.

MEMS Sensor 2 (Nunchuk)
Many games on the Wii take advantage of a second controller, called the
Nunchuk, which plugs into the Wii Remote. It features an analog joystick and
two buttons, but it also has its own MEMS accelerometer, this one provided by
STMicroelectronics. Benedetto Vigna, an STMicroelectronics physicist, says
that the company's three-dimensional accelerometer had a "really quick"
development time; the company first met with Nintendo about the Wii in March
2005, only nine months before the product shipped. Vigna notes that there are
two chips inside the 5-millimeter-by-5-millimeter-by-1.5-millimeter plastic
package--the accelerometer and another chip that translates the tiny wiggles
of the sensor into voltage. As in the Wii Remote, the voltage readings are
then translated into motion data by a microprocessor, and the data are
transmitted wirelessly from the Wii Remote via Bluetooth to the Wii console.

Infrared Sensor Bar
The accelerometers in the controls gauge movement but not position relative
to the TV screen. So the Wii comes with a "sensor bar," to be placed at the
top or bottom of the screen. The bar sends out an infrared signal, which is
picked up by detectors at the front of the Wii Remote. The Remote uses
distance and angle information to triangulate its location, which it sends,
along with acceleration data, to the console.

Wi-Fi
Nintendo saw the value of adding Wi-Fi wireless connectivity to its popular
DS handheld gaming device, which allowed users to play against others
wirelessly, so it did the same with the Wii. If you have an Internet
connection, you can use the Wii to surf the Web or access information hosted
on Nintendo's servers, such as weather and news. Developers have said there
will be Wii games that offer online play, though as of this writing only
one--a Pokémon title--has been released.

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