Telenetics Global Carrier, User Manual

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Glossary
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Control Character
Any character assigned as ASCII numeric code less than the SPACE character. These characters
are used to initiate a control function on the receiving device. Also a symbol you can create by
pressing one of your computer’s keys while holding down the Control key. These symbols are
not usually printed, and are generally used to control screen formatting and cursor positioning.
CPU
Central Processing Unit. The computer hardware which processes software instructions to
control the computer system and its peripherals.
CRT
Cathode Ray Tube. This term is commonly used to stand for the video display terminal.
CTS
An acronym for Clear To Send. This signal is generated by a modem in response to RTS to
indicate that a communications channel has been established and that data can be sent.
Cyclic Redundancy Check
An error-detection technique in which a data validation value is mathematically derived from a
block of data and transmitted at the end of the block. The receiving end recomputes the value
and if it matches the value sent, the data is assumed to be valid (error-free). If not, the receiver
notifies the transmitter that an error has occurred and the block is retransmitted.
D
Data
Any type of information, such as numbers, letters and symbols, that can be processed by a
computer.
Database
A source or collection of information. In the context of communications, a dialup service from
which users can exchange or retrieve information.
Data Bits
The actual characters being transmitted between two computers when asynchronous
communications is being used. Usually 7 or 8 data bits are used.
Data Communications
A broad term covering any exchange of information between computers or similar systems over
telephone lines.