Mitel SX-200 DIGITAL Pabx General Description Manual

							Features Description 
Connection Memory 
Part of the DX chip which is used to store the digital voice (or data) 
samples. These samples are stored and forwarded under the control of 
the MCC. 
Consultation Hold (Soft Hold) 
This type of call hold facility is also termed soft hold and is a form of 
temporary hold. It is used to place a second party on hold, while the 
first party is speaking (consulting) with a third party, or otherwise 
wishes to temporarily isolate the second party from conversation. 
Critical Alarm 
See Major Alarm. 
Cross-Connect Field 
See Main Distribution Frame 
Customer Data Entry (CDE) 
Customer Data Entry is the process employed when data, particular to 
a specific customer installation, is entered into the SX-200@ DIGITAL 
PABX System. This data includes such things as numbering plan, ARS 
r-outings, trunk descriptors, etc. CDE is entered into the SX-200: DIGI- 
TAL PABX via the MaintenanceKDE terminal. 
DCE 
See Data Communication Equipment 
DIC 
See Digital Interface Card. 
DID 
Direct Inward Dialing. 
DIL 
Direct-In Line. 
DOD 
Direct Outward Dialing. 
DLIC 
See Digital Line Interface Circuit. 
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							Features Description 
DSP 
See Digital Signal Processor. 
DTMF 
Dual Tone Multifrequency Signaling. 
DTE 
See Data Terminal Equipment 
DX 
The term used in the SX-200@ DIGITAL PABX to represent the expres- 
sion “digital crosspoint” which is used as the fundamental switching 
element of the SX-200@ DIGITAL PABX Circuit Switch. The Circuit 
Switch is composed of a large number of digital crosspoint switch 
elements in the form of DX chips, assembled on a plug-in Circuit 
Switch module. 
Data Communication Equipment 
Data Communication Equipment (DCE) is the term used to describe 
that equipment which is employed as an interface between a commu- 
nications line and Data Terminal Equipment (DTE). In general this inter- 
face accepts the data communication signals and the necessary con- 
trol signals, over an RS-232 line from the DTE, and transforms them 
into the appropriate signals which are required to be sent over the 
communications path to the distant DCE and DTE. These line signals 
usually consist of modulated tone signals. Tone signals demodulated 
by the DCE at the distant terminal are reconverted into the relevant 
data and control signals. The data circuit is commonly a dupiex circuit, 
i.e capable of operation in both directions simultaneously. 
Data Terminal Equipment 
Data Terminal Equipment (DTE) is terminal equipment usually consist- 
ing 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 
This term refers to 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@ DIGITAL PABX for example is 
a value of 1 minute allowed before an unanswered ringing extension 
times out. However this value may be changed from the default value, 
during CDE programming, to a value which lies between 1 and 5 
minutes. 
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							Features Description 
Digit Modification 
This expression refers to the process of restructuring a dialed se- 
quence of digits received by the SX-200@ DIGITAL PABX which effec- 
tively results in the production of a different sequence of digits. The 
revised sequence may have new digits added and/or digits deleted 
(absorbed), or certain digits in the original sequence may be repeated. 
This process is performed automatically by the SX-200@ DIGITAL PABX 
and is thus transparent to the user. Digit Modification is used in Speed 
Dialing operation: tandeming of trunk circuits, in processing incoming 
DID calls, in processing calls in ARS and other applications. 
Digital Interface Card 
This card interfaces the analog cards in the analog bays to the digital 
switching network (the Circuit Switchj, and the rest of the system. 
Digital Signal Processor (DSP) 
This is a single chip processor capable of both tone detection and tone 
generation. Located on the Main Control card, the DSP generates and 
detects all of the call progress and DTMF tones used by the SX-200@ 
DIGITAL PABX. 
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 
purposes (see also Analog/Digital). 
Digital Line Interface Circuit 
The Digital Line Interface Circuit (DLIC) is a Mite1 chip, which is de- 
signed to handle 256 kbits/s data transmitted between the SX-200@ 
DIGITAL PABX and high-speed digital synchronous DTEs (i.e9 the At- 
tendant Console). 
E and M 
The term applied to a type of tie trunk, and also to the signaling 
method used for this and for other types of trunks. The term is derived 
from the use of the E and M leads, forming part of the trunk equip- 
ment, and taken respectively to denote the receive and transmit leads; 
the two leads being used to pass supervisory conditions over the 
trunk. 
Forced Account Code 
The Forced Account Code feature requires that when it appears in a 
particular station’s COS, the user at that station must dial a valid 
account code each time that an outgoing trunk call is made. If it is not 
entered the user will be denied access to the trunk. The account code 
will appear as part of the SMDR record. 
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							Features Description 
Full Duplex 
A method of operation which allows simultaneous transmission from 
both ends of a communications link 
Ground Button 
See Recall Button 
Ground Start 
The term used to designate a particular type of trunk circuit, on which 
a ground condition is applied to the ring lead of the trunk when an 
outgoing call seizes the trunk. 
Group Hunting 
Group Hunting is a feature which allows certain stations to be formed 
in groups so that incoming calls are directed to the group by dialing a 
master number. A group can be arranged as a: 
m Circular group, in which case the stations are searched in a 
circular manner commencing with the called station. 
l Terminal group, in which case the stations are searched stat-t- 
ing at the first station and ending with the last station in the 
group. 
, 
Hard Hold 
Hard Hold is the term used when a station user, or an attendant, places 
another party on hold, and can then perform any of the functions 
which are normally available at the station (as opposed to Consultation 
Hold, which restricts the functions which can be performed). 
Hot Repair 
This term is applied, when a system has the ability of allowing main- 
tenance or repair action to be performed, without first removing power 
from the system. 
Intelligent Terminal 
An Input/Output device, usually with a keyboard for input and a VDU 
for output, which has local storage and a processor enabling it to 
perform certain tasks independently. 
Interconnection Restrictions 
Certain interconnections between stations and trunks, and between 
trunk and trunk circuits are not allowed for various reasons. These 
interconnections are prevented by setting appropriate parameters in 
the Device Interconnection Table which is programmed as part of the 
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							Features Description 
SX-200” DlGlTAL PABX CDE procedures. Calls made to trunk circuits 
are thus subject to the parameters in the Table. 
Least Cost Routing 
Least Cost Routing is one of the functions of Automatic Route Selec- 
tion and refers to the economical aspects of the ARS facility. In Least 
Cost Routing, the trunk circuits are programmed, with regard to the 
effects of the costs of the possible alternative trunk routings. In prac- 
tice the customer may require the economical aspects to be subordi- 
nate to the overall traffic efficiency requirements of the System; for 
example, less costly trunk routes may be available, but offer too low a 
traffic grade of service for the customer’s needs. Actual requirements 
may be subject to Traffic Analysis of the customer’s needs. 
Loop Start 
A form of signaling used by a certain ‘type of CO trunk, which des- 
ignates that type of trunk. It denotes an outgoing trunk circuit which is 
seized by the system placing a “loop” condition on the trunk. 
Loop Pie Trunk 
The term applied to a tie trunk between PABX’s, which is seized by the 
application of a “loop” condition on the trunk. Subsequent supervisory 
conditions may be determined by the presence/absence of the loop or 
by battery-reversal conditions. 
MCC 
See Main Control Card 
MDF 
See Main Distribution Frame 
MPU 
Main Processing Unit - in the case of the SX-200@ DIGITAL PABX, this 
refers to the 68000 CPU on the Main Control card. 
Main Control Card (MCC) 
The Main Control Card is the main hierarchical intelligence of the 
SX-200’ DIGITAL PABX. It contains the CPU (Central Processing Unit), 
DRAM (Dynamic Random Access Memory), disk interface elements, and 
is responsible for the overall operation of the machine (including call 
processing, record keeping, maintenance functions and system control 
functions). 
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							Features Description 
Main Distribution Frame 
The Main Distribution frame (MDF) forms the interconnection point 
between the in-house PBX (for example the SX-200@ DIGITAL PABX), 
and the internal 
and external cabling to the PBX. The MDF provides a 
convenient and flexible means of interfacing the cabling to the system. 
The MDF is also known as the Cross-Connect Field. 
Maintenance Panel 
The Maintenance Panel of the SX-200@ DIGITAL PABX performs a 
variety of functions, including the following: 
l Allows access to the maintenance facilities via an RS-232 port, 
an RJ-11 jack, or banana plugs. 
0 Allows maintenance personnel to manually switch plane activi- 
ties (where redundant systems are installed), and perform other 
maintenance activities. 
Major Alarm 
One of three possible type of alarm priorities, which are the Minor, 
Major and Critical Alarms. As the names imply, fault conditions which 
may arise on the SX-200@ DIGITAL PABX can be segregated into 
different categories of urgency, which are then subsequently handied 
according to the degree of urgency. 
Message Subsystem 
The Message Subsystem is one of the subsystem blocks of the 
SX-200@ DIGITAL PABX. It’s function is to act as the main message 
collection and distribution facility for the system, and links the Main 
Controller with the intelligent entities at the peripheral level or below. 
In effect it is the “nervous” system of the SX-200@ DIGITAL PABX, in 
that it passes messages and commands between the lowest and high- 
est levels of the system. 
Minor Alarm 
See Major Alarm 
Mixed Station Dialing 
The SX-200@ DIGITAL PABX caters to the use of both rotary dial 
and/or DTMF types of station sets installed on the system. 
Multiple Consoles 
More than one attendant console may be installed on an SX-200@ 
DIGITAL PABX System. The trunk groups can be arranged to terminate 
such that they can be accessed from all of the consoles, and any call 
can be answered from any console. 
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							Features Description
Null Modem
This item can take various forms, but its function is always the same;
it enables connections to be made between two “modems” on a back-to-back basis The main characteristic of the Null modem is to trans-
pose the RS-232CS and R leads which interconnect the “modems”;
otherwise the send (S) leads of the two “modem” will be connected
together, as will the two receive (R) leads. A typical example of the use
of a Null Modem is it’s employment, in the form of an adapter added to
the RS-232C cable, when connecting a 
Dataset to a modem to form a
Modem Element which is used in a Modem 
Hunt Group.
ONS
See On-Premises Stations
OPSSee Off-Premises Stations
Off-Premises Stations
Stations which are located at a considerable distance from the parent
communication system, and require special circuit terminating ar-
rangements at the PBX, are referred to as Off-Premises (OPS) stations.
On-Premises Stations
Stations which are installed on the same premises as the PBX, or
which can operate satisfactorily with the PBX, when installed in adja-
cent premises without special circuit arrangements, are known as
On-Premises (ONS) Stations.
Overlap Outpulsing
Overlap Outpulsing is a feature used in the 
SX-2QO@ DIGITAL PABX
when making trunk calls. It results in 
dial pulses (or tones) being
outpulsed prior to the receipt of all required digits from the user, the
purpose being to reduce the time needed to process the call.
PCBPrinted Circuit Board
PCCSee Peripheral Control Card
PCM
Pulse Code Modulation
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							Features DescriptionPLIDPhysical Location 
IDentity - the bay number, slot number, circuit num-
ber and sub-circuit number of a device. Eg. a DTMF Receiver circuit
‘plid’ might be: Bay 2, Slot 3, Circuit 2, Sub-circuit 1.
Peripheral Control Card
This. card controls the operations within the analog peripheral bays,
and is under control of the Main Control card.
Peripheral Equipment
Periphersl Equipments, with regard to the 
SX-200@ DIGITAL PABX, is
understood to be all those external equipments which are connected
to the 
SX-200@ DIGITAL PABX, such as stations, sets, trunks, attendant
consoles, and maintenance terminals.
Peripheral interface
Peripheral Interface cards are cards which provide the interface facili-
ties between the external peripheral equipments, such as stations,
trunks and attendant consoles. One of their prime functions is to
convert the external analog inputs to the internal digital PCM signals
’(and conversely convert digital PCM to.analog output).
Power Fail Transfer
The System Fail Transfer feature allows selected stations of the Sys-
tem (or portions of the System, according to the type of outage), to be
transferred to certain trunks. Such transfer action is accomplished
automatically in the event of a failure of the main power supply.
Transfer action is also accomplished on a “zone” basis in the event of
power failure occurring, for example, on a peripheral shelf.
RS-242C
A North American data interchange standard, issued by the Electronics
Industries Association (EIA). The equivalent European standard is the
W.24 specification.Recall Button
This refers to the push-button installed on certain types of telephone
station sets, for the purpose of providing a ground condition to line,
when the button is pressed. When used in conjunction with the
SX-200@ DIGITAL PABX, pressing the Recall button corresponds to a
switchhook flash; for example, when a patty is being placed on hold.
The button is sometimes referred to as the Ground button.
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							-Features Description
Ring Lead
The second wire of a telephone pair (the first being the Tip Lead), so
named because it was originally connected to the “ring’ of a telephoneplug.SMDR
See Station Message Detail Recording
Scanner Card
This card continuously scans all of the analog ports in the anaiog bays
to detect signals which require processor action.
Second Dial Tone
A user making a trunk call through a PABX System normally receives
dial tone after the handset is removed, and then dial tone from the CO
after the trunk access code has been dialed. The 
SX-200@ DIGITAL
PABX however, with its ARS feature would mask the CO dial tone,
because the outpulsing sequences are isolated from the user. To pre-
vent confusion a second dial tone can be provided to the user (as a
programmable option) by the 
SX-ZOO@ DIGITAL PABX, at the appro-
priate point in the outpulsing sequence.
Side Tone
This is the portion of the transmitted voice signal that is returned to
the receiver of the transmitting extension.
Soft Hold
See Consultation Hold.
Station Message Detail Recording (SMDR)
Station Message Detail Recording (SMDR) is a facility which records
and prints out the details of incoming and outgoing trunk calls in the
SX-200@ DIGITAL PABX. Such details include the numbers of all parties
involved in the call, the time and duration of each call, account codes
and other pertinent details. Section 
MITLg108-093-451 -NA, Station
Message Detail Recording should be consulted for details of SMDR.
Stop Dial
In tandem trunk operations it may be necessary, during the course of
establishing a call, to suspend the dialing of dial train sequences‘ This
is to ensure that no digits are lost, due to the next link in the tandem
connection not being ready to receive the digits. The Stop Dial feature
is employed to stop the outpulsing of further digits, by sending an
on-hook condition to the originating end of the circuit.
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							Features Description
Store and Forward Dialing
See Overlap Outpulsing
Synchronous Mode
This term is associated with data which is transmitted in a continuous
stream at a fixed rate, with the receiving terminal synchronized to the
transmitting terminal by means of sync elements transmitted on a
regular basis. See also Asynchronous Mode.
System Configuration
The term System Configuration has a specific meaning for theSX-200@ DIGITAL PABX, in that it refers to the particular hardware and
software initially installed for the System. Any subsequent additions,
deletions and any other changes which occurs results in a new System
Configuration being created. The listing of hardware and software
items which comprise the current System Configuration can he ob-
tained on command from the maintenance terminal.
System Fail Transfer
See Power Fail Transfer
TCM
Transition Code Modulation.
TTY
This abbreviation is in common use to denote a teletypewriter ma-
chine.
Tandem Trunking
Tandem Trunking describes the facility of transparently switching 
co-located trunks together at the 
SX-200m DIGITAL PABX. This type of
switching is subject to Digit Modification, and the parameters pro-
grammed during CDE for the Interconnection Restrictions table.
TelcoThe abbreviation used to denote Telephone Company.
Tie Trunks
Tie Trunks 
direct!y interconnect two PABX systems together. This en-
ables a station, terminated on one of the systems, to be 
intercon-
.netted to any other station, terminated on the other system. With
Tandem Trunking the calling party can be extended through more than
one node (PABX) of the network.
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