A: Think of USB as a smart plug for PC peripherals. USB automatically determines
resources (like driver software and bus bandwidth) required by peripherals. USB
makes necessary resources available without user intervention. There are three main
benefits of USB. USB eliminates "case anxiety," the fear of removing the computer
case to install circuit board cards -- that often requires adjustment of complicated IRQ
settings -- for add-on peripherals. USB does away with "port gridlock." Without USB,
PCs are normally limited to one printer, two Com port devices (usually a mouse and
modem), one Enhanced Parallel Port add-on (scanner or video camera, for example),
and a joystick. More and more peripherals for multimedia computers come on the
market every day. With USB, up to 127 devices can run simultaneously on one
computer. USB permits "hot plug-in." No need to shut down, plug in, reboot and run
set up to install peripherals. No need to go through the reverse process to unplug a
device. Bottom line: USB transforms today's "Plug-and-Pray" into true Plug-and-Play!
Please refer to glossary for more information about USB.
Q: What is a USB hub ?
A: A USB hub provides additional connections to the Universal Serial Bus. A hub's
upstream port connects a hub to the host, usually a PC. Multiple downstream ports in
a hub allows connection to another hub or device, such as a USB keyboard, camera
or printer.
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LCD Panel Technology
Q:
What is a Liquid Crystal Display?
A: A Liquid Crystal Display (LCD) is an optical device that is commonly used to
display ASCII characters and images on digital items such as watches, calculators,
portable game consoles, etc. LCD is the technology used for displays in notebooks
and other small computers. Like light-emitting diode and gas-plasma technologies,
LCD allows displays to be much thinner than cathode ray tube (CRT) technology.
LCD consumes much less power than LED and gas-displays because it works on the
principle of blocking light rather than emitting it.
Q: How are LCDs made?
A: LCDs are created from two glass plates separated from each other at a distance
of a few microns. The plates are filled with liquid crystal and then sealed together.
The top plate is colored with an RGB pattern to make the color filter. Polarizers are
then glued to both plates. This combination is sometimes called 'glass' or 'cell.' The
LCD cell is assembled into a 'module' by adding the backlight, driver electronics and
frame.
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