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Broadcast, Buffer, Clipboard – Wavecom W-SPECTRA (Automatic Monitoring System) V1.1.0 User Manual

Page 280: Context sensitive, Control key, Database management system, Default button

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Glossary of Terms

WAVECOM Monitoring System W-SPECTRA, W-SPEED Manual V1.1.0

The speed is given as the channel speed in Bauds. For two level modulation types this equals the raw user
bit rate, for four level s the bit rate is doubled, for eight levels it is tripled etc.

Broadcast

Public or private radio station transmitting music, news, etc.

Buffer

A temporary holding area in the computer's memory where information can be stored. In editing, it is an
area in memory where cut or copied data is held, sometimes called the clipboard. See also: clipboard and
type-ahead buffer.

Clipboard

The holding place for what you last cut or copied; a buffer area in memory. Information contained on the
clipboard can be inserted (pasted) into other documents and other WINDOWS applications.

Context sensitive

Able to perceive the situation in which an event occurs. For example, context sensitive help presents in-
formation specific to the particular task you are performing, rather than presenting just a general list of
commands.

Control key

A specific key, usually abbreviated as "Ctrl", that produces control characters when used in combination
with character keys.

CRC

A cyclic redundancy check (CRC) is an error-detecting code designed to detect accidental changes to raw
data, and is commonly used in digital data transfer and storage. A CRC-enabled protocol calculates a
short, fixed-length binary sequence, known as the check value or improperly the CRC, for each block of
data to be sent or stored and appends it to the data, forming a codeword. When a codeword is received or
read, the device either compares its check value with one freshly calculated from the data block, or equiv-
alently, performs a CRC on the whole codeword and compares the resulting check value with an expected
residue constant. If the check values do not match, then the block contains a data error and the device
may take corrective action such as requesting the block be sent again, otherwise the data is assumed to
be error-free (though, with some small probability, it may contain undetected errors; this is the funda-
mental nature of error-checking).

CRCs are so called because the check (data verification) code is a redundancy (it adds zero information to
the message) and the algorithm is based on cyclic codes. CRCs are popular because they are simple to
implement in binary hardware, are easy to analyze mathematically, and are particularly good at detecting
common errors caused by noise in transmission channels. As the check value has a fixed length, the func-
tion that generates it is occasionally used as a hash function.

Database management system

(DBMS) - A software system for organizing, storing, retrieving, analyzing and modifying information.

Default button

The push button with a bold border in dialogues. The default button often has a dotted-line border around
the button name. The default button is chosen when you press "Enter" (or Ctrl+Enter depending on your
configuration).