BR-Automation Automation PC 820, Руководство пользователя

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Appendix A • Glossary
Automation PC 820 User's Manual V 1.00
Switch
Device, similar to a hub, that takes data packets received in a network and, unlike a hub, does
not pass them on to all network nodes, instead only to the respective addressee. Unlike a hub,
a switch provides targeted communication within a network that only takes place between
sender and receiver. Other network nodes are not involved.
SXGA
Abbreviation for Super Extended Graphics Array. Graphics standard with a screen resolution of
1280 × 1024 pixels (aspect ratio 5:4).
SXGA+
Abbreviation for SXGA Plus; Generally 1400 × 1050 pixels.
Task
Program unit that is assigned a specific priority by the real-time operating system. It contains a
complete process and can consist of several modules.
TCP/IP
Transmission Control Protocol/Internet Suit of Protocols. Network protocol that has become the
generally accepted standard for data exchange in heterogeneous networks. TCP/IP is used both
in local networks for communication between various computer and also for LAN to WAN
access.
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 activating an item with 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.
T