Boca SoundExpression 14.4VSP, User Manual

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break handling . Determines how the modem responds when a BREAK signal is received from
either the DTE (Data Terminal Equipment or computer/terminal) or the remote modem. This is
controlled by the MNP-based AT extended command \K. A break signal is represented on the
communications line by a steady space signal for a significant length of time. Break signals may
be activated from the keyboard by pressing the BREAK key or the control (CTRL) and C keys.
C
CCITT
. Consultative Committee for International Telephone and Telegraph. This advisory
organization is part of the ITU (International Telecommunication Union) which is an agency of
the United Nations. Organization recently renamed International Telecommunications Union-
Telecommunications Standard Sector (ITU-T)
command mode
. The modem is in command mode when it is turned on or reset, when it loses
its connection to a remote modem, when it is in on-line mode, or when escape characters (+++)
are typed. To transmit data, the modem must be in data mode. The modem does not transmit
data when in command mode.
communications protocol
. A set of procedures which controls how a data communications
network operates.
D
DCD
. Data Carrier Detect. Indicates to the terminal device that the modem is receiving a valid
carrier signal from a remote modem. The carrier is a tone at a specified frequency.
DCE . Data Communications Equipment. The local and/or remote modem. A DCE is usually
connected to a DTE.
DTE . Data Terminal Equipment. The computer or terminal, either local (yours), or the remote
(the one you’re communicating with). A DTE is usually connected to a DCE.
DTR . Data Terminal Ready. The computer issues this signal to the attached modem indicating
that it is ready to receive data.
data compression . A technique that examines transmitted data for redundancy and replaces
strings (groups) of characters with special codes which the receiving modem interprets and
restores to its original form. Transmission of compressed data results in shorter connect times
and hence cost savings for connect charges. Data compression is sometimes called “source
encoding”.
data mode . The modem is in data mode when a connection has been established with a remote
modem and sends a CONNECT response confirming the connection. User data may then be
transmitted or received.
Glossary of Modem Communication Terms