Mitel SX-2000 EL, Information Manual

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Glossary of Terms
50003510 Revision A 235
DTMF
Dual tone multifrequency signaling.
DTR
Data terminal ready RS-232 pin.
DTRX
Data transceiver.
DX
An abbreviation of the term digital crosspoint, the fundamental switching element of the SX-200
EL/ML circuit switch. The circuit switch is composed of a large number of digital crosspoint
switch elements in the form of DX chips.
Data Communication Equipment
Data communication equipment (DCE) interfaces a communications line or data device to data
terminal equipment (DTE) over an RS-232 line. A modem and the local maintenance port on
the SX-200 EL/ML system are examples of a DCE.
Data Terminal Equipment
Data terminal equipment (DTE) is terminal equipment, usually consisting of a keyboard and
video screen or printer, which is used to communicate with a variety of other equipment (i.e.
another DTE or a computer).
Default
The value assigned to a particular function which most nearly represents the normal or standard
value of the function. A typical default value used in the SX-200 EL/ML system, for example,
is a value of 2 minutes allowed before an unanswered ringing extension times out. However
this value can be changed in CDE programming from the default value to a value which lies
between 1 and 30 minutes.
Digit Modification
The process of restructuring a dialed sequence of digits received by the SX-200 EL/ML system
to effectively result in a different sequence of digits. The revised sequence can have new digits
added and/or digits deleted (absorbed); or certain digits in the original sequence can be
repeated. This process is performed automatically by the SX-200 EL/ML system and is
transparent to the user. Digit modification is used in speed calling, tandeming of trunk circuits,
processing incoming DID calls, processing calls in ARS, and other applications.
Digital/Analog
A term used in connection with the conversion of digital signals to equivalent analog signals.
The original signals are usually in analog form and are converted from analog to digital signals
for transmission (see also Analog/Digital, page 229).