B&R MAPPC800-ENG, Руководство пользователя

Страница: 376 / 396

376
Appendix A • Glossary
Panel PC 800 User's Manual V 1.00
TFT display
LCD (Liquid Crystal Display) technology where the display consists of a large grid of LCD cells.
Each pixel is represented by a cell, whereby electrical fields produced in the cells are supported
by thin film transistors (TFT) that result in an active matrix. In its simplest form, there is exactly
one thin film transistor per cell. Displays with an active matrix are generally used in laptops and
notebooks because they are thin, offer high-quality color displays and can be viewed from all
angles.
Touch screen
Screen with touch sensors for selecting options in a displayed menu using the tip of the finger.
TXD
An abbreviation for "Transmit ( TX ) D ata". A line for the transfer of serial data sent from one
device to another, e.g. from a computer to a modem. For connections complying with the RS-
232-C standard, the TXD is connected to pin 2 of the plug.
UART
An abbreviation for " U niversal A synchronous R eceiver- T ransmitter". A module generally
consisting of a single integrated circuit that combines the circuits required for asynchronous
serial communication for both sending and receiving. UART represents the most common type
of circuit in modems for connecting to a personal computer.
UDMA
An abbreviation for " U ltra D irect M emory A ccess". A special IDE data transfer mode that allows
high data transfer rates for drives. There have been many variations in recent times.
UDMA33 mode transfers 33 megabytes per second.
UDMA66 mode transfers 66 megabytes per second.
UDMA100 mode transfers 100 megabytes per second.
Both the mainboard and the hard drive must support the specification to implement
modifications.
UPS
Abbreviation for " U ninterruptible P ower S upply". See "UPS".
USB
An abbreviation for " U niversal S erial B us" A serial bus with a bandwidth of up to 12 megabits per
second (Mbit/s) for connecting a peripheral device to a microcomputer. Up to 127 devices can
be connected to the system using a single multipurpose connection, the USB bus (e.g. external
CD drives, printers, modems as well as the mouse and keyboard). This is done by connecting
the devices in a row. USB allows devices to be changed when the power supply is switched on
(hot plugging) and multi-layered data flow.
U