|PXML No. 43
APPROVAL No. NS/1412/GF/1981/PR & NS/1000/GF/1981/PR
Click here to see information on BT's withdrawal of
Subscribers Private Metering (SPM)
the BT marketing name for the Mitel SX200.
Marketing names used by non-BT suppliers may be SX200, ROYALE, SUPERSWITCH.
(SX200 with 247 console)
The SX200 is 256 port Call Connect System (CCS), of which 184 ports are available for
assignment to extensions, trunks and private circuits (the remainder are used for
receivers, special functions and the common control). The systems capacity depends on how
these ports are used, as an extension uses one port, a trunk uses two ports and a private
circuit uses four ports.
The maximum size of the system is actually 24+134.
Regent is an SPC switch utilising CMOS switching and a MC6800 CPU supported by 8k of RAM.
The generic (system operating programme) is stored in 56K of programmable ROM and there is
also 4K of battery backed up RAM that contains access code and extension information.
Speech is analogue using 31 speech paths connected to every port on the system.
The system is housed in a floor standing cabinet of size 960 mm high, 600 mm wide and 700
mm deep and weighing 132 kg when fully equipped.
Various generics are approved:-
Generic 245 (these had white consoles)
Generic 345 (SX200, non-BT supply only. Cannot support supersets/TX14).
Generic 247 (these had black consoles)
Generics 248/250 are approved (non BT).
The Customer database is held on battery backed RAM on the Integrated Processor Control
G245 customers cannot change data base (thumbwheels inside cabinet) Other generics have
default database and limited programming by customers.
Extension cards contain eight ports, trunk cards 4 ports and private circuit cards two
ports. The system also supports TX14/Superset 4 featurephones that
operate on special extension cards.
Introduced into the UK mid 1982 and initially available only in BT regions BTE, BTNW and
the City of London.
The SX200 is sold through a number of distribution routes in the U.K. and as a consequence
may be badged as follows: Casstel, Royale, SX-200 & Regent.
Made by Mitel Telecom Ltd. Severnbridge Industrial Estate, Portskewett, NEWPORT, Gwent.
Telephone 01291 430000
For liberalisation purposes, the equipment is classed as an analogue PABX.
Approval has been granted for a networking arrangement for multipled SX200s. Each
networked site is granted specific connection approval by Technology Applications
Batteries on memory/IPC cards require renewal every 4 years. As later cards have hard
wired batteries, this will necessitate returning the card to MITEL. System standby
battery, if fitted, also requires renewal every 4 years.
NB: Due to the possibility of batteries rupturing, hence causing leakage, it is essential
that the renewal period of both types of battery are strictly adhered to.
Remove or switch off RAM batteries from memory cards prior to transportation and use the
appropriate antistatic bags (the clear type are only conductive on the outside and should
be used in this instance).
The PSU (back door) and Standby Battery Pack are extremely heavy to lift and install by
This instruction describes the 245 variant
C MARKETING INSTALLATION
Issue 2, Mar 1982
REGENT CALL CONNECT SYSTEM DESCRIPTION
3 SYSTEM OVERVIEW
5 PHYSICAL DESCRIPTION
6 SYSTEM ASUs
7 CALL PROCESSING
This TI provides a description of Regent. Other related Regent TIs are:-
Regent Call Connect System - Installation Planning F3022
Regent Call Connect System - Configuration F3023
Regent Call Connect System - Installation and Commissioning F3024
Regent Call Connect System - System Connection Boxes F3025
Regent Call Connect System - Maintenance E5 D2160
Regent Call Connect System ~ Sales Overview B4 F4020
Regent Call Connect System - Sales Procedure B3 B0071
Further detailed information is given in:-
ITEM CODE DESCRIPTION 37 3841 Regent Handbook 9110-032 (2 Volumes)
3 SYSTEM OVERVIEW
Regent is an electronic PABX using digitally controlled space division switching and
stored program control.
The system capacity is 256 ports. 184 ports are available for assignment to extensions,
exchange lines and private circuits. The remaining ports are used for receivers, special
functions and the common control.
An extension uses 1 port, exchange line 2 and private circuit 4.
For BT use the maximum size of system is normally 24 exchange lines, 136 extensions. 2
of these extensions are reserved for BT maintenance use. The maximum number of connections
possible at any time Is 31.
A system is built to customer order size by the provision (or removal) of Apparatus
Slide-in Units (ASUs). Extension ASUs have 8 circuits, exchange line ASUs 4 and private
circuit ASUs 2.
At present software operating program codes generic 245 is standard, other generics
offering different facilities may be introduced. Generic 245 facilities are listed in
Regent Handbook 9110-035 Volume 1 Section MITL9110-98- 105 (BT).
Circuit malfunctions are detected by diagnostic routines automatically initiated by the
Central Processing Unit (CPU). Together with the functional packaging of the equipment
these routines will in most cases locate faults to a particular ASU. Preventative
maintenance is limited to the occasional replacement of memory protection and (if
provided) standby power unit batteries.
5 PHYSICAL DESCRIPTION
The equipment cabinet is 965 = high, 600 mm wide and 700 mm deep. Fully equipped with ASUs
it weighs 132 kg.
The front door of the equipment cabinet gives access to the maintenance panel, ASUs and
standby power supply shelf. The rear door holds the system power supply and gives access
to the connectors used for linking the system to a frame, emergency switching circuitry
and the standby power controls. Cable entry is through holes at either side at the bottom
of the cabinet.
Mounted at the top inside the front of the cabinet. A connector is provided for a
maintenance console. The the left of this connector are the emergency switching control
switches. On the extreme left are terminals for a test extension.
Allows system access for maintenance tasks and entering new, or modifying existing
customer configuration data.
Equipment shelf 2 is directly underneath the maintenance panel. Equipment shelf 1 is below
equipment shelf 2. Equipment shelf 1 holds a maximum of 22 ASU's. ASU slots are allocated
to common control ASU's, console control, tone and receiver ASUs and some extension ASU's.
Equipment shelf 2 holds a maximum of 14 ASU's, extensions, exchange lines and private
circuits. Lines are extended from the equipment by connectors plugged into the rear of the
equipment shelf backplanes.
The system primary power supply is mounted on the back door of the equipment cabinet. 240v 50 Hz mains power input is converted to the voltages required by the system. The
optional standby power unit is contained in a completely enclosed shelf assembly which
fits beneath equipment shelf 1.
|Console - 245 model
||Console - 247 model
The console keyboard (shown above) has 3 rows of 10 non-locking keys for selection of
facilities and control of calls. To the right of the keyboard is a push button keypad. The
console display, mounted above the keyboard displays the state of calls in progress. There
is a busy lamp field, a trunk group status display, a call waiting indicator, a digital
clock and 3 alarm indicators. The console is connected by plug ended cable to the
Emergency Switching Circuits
12 circuits which connect exchange lines through to standby equipment or dedicated
extensions are mounted on a printed wiring assembly fitted in the back left hand side of
the equipment cabinet. These circuits are extended from the cabinet by plug ended cables.
6 SYSTEM ASU's
8 circuits which interface extension apparatus to the PABX interconnecting speech paths
via a switching matrix mounted on the ASU.
Exchange Line ASU
4 circuits which interface the lines from the serving exchange to the PABX interconnecting
speech paths via a switching matrix mounted on the ASU.
2 circuits which can detect both 10 pps and ssmF4 signals from extensions and transfer
them to a temporary store during call processing.
Console Control ASU
Interface between the switching matrix and common control for 1 operator console and 1
Tone Control ASU
This ASU supplies all call progress tones and houses dial pulse generators, voice paging
circuitry and diagnostic testing functions.
Sequentially scans all parts to detect signals which require processor action. Also
contains the night bell and paging control relays.
Contains part of the system operating software in a PROM daughter ASU which plugs onto the
CPU ASU. The CPU ASU contains the system controlling microprocessor and associated
PROM/RAM Expander ASU
Contains RAM store for customers abbreviated dialling and call barring information. A
battery is mounted on this ASU which will retain RAM information during power failure.
RAM for customers configuration data and call processing transient record. A battery is
mounted on this ASU which will retain RAM information during power failure.
Private Circuit ASU
ASUs to provide SSAC13, SSAC15, SSDC5 and Loop bothway signalling, 2 circuits per ASU are
available. An externally mounted ASU to interface Regent mounted 2 wire SSDC5 to SSDC10 is
available, 2 circuits per ASU.
7 CALL PROCESSING
Extension Originating a Call
Lifting an extension handset draws line current. This is detected by an operational
amplifier on the extension ASU. A light emitting diode (LED) on the front of the ASU is
illuminated and an off hook signal set for the particular extension. This signal, together
with signals from the other 7 extensions on the ASU are presented to an analogue switch.
The scanner, which is continuously examining all lines every 3.2 ms, addresses each
extension via the IA bus. The off hook signal is presented on the IZ line for the
particular ASU. The change of IZ line condition causes the scanner to stop scanning and
interrupt the processor via the IRQ line. The scanner presents the extension, ASU address
and the IZ line condition to the data bus which the processor reads while restarting the
Operator Console Originating a Call
The console does not generate an off hook signal. Provided that the handset is plugged in
it is only necessary to depress the key of the first digit required.
Connection of Dial Tone To An Extension
When the processor recognises an off hook condition it interrogates RAM to identify a free
speech path which it checks using the diagnostic circuitry on the tone control ASU. The
tested speech path is then connected to the extension circuit. The processor searches for
an idle receiver and then dial tone. The processor then connects the selected receiver and
dial tone to the same speech path using the ASU select, address and data lines. Dial tone
is heard at the extension.
Extension Dialling An Internal Number
SSMF4 or 10 pps signals from an extension are passed through the extension line circuit to
a speech path and then to a receiver. The receiver detects either type of signal. SSMF4 is
recognised using filter circuits, 10 pps pulses are decoded by a pulse counter. The
receiver sets an interrupt signal and when the scanner addresses it, the interrupt is
placed on the IZ line of the receiver ASU. The change on the IZ line causes the scanner to
stop and to interrupt the processor via the IRQ line. The scanner presents the receiver
and ASU address to the data bus which the processor then reads while restarting the
scanner. The processor reads the digit from the receiver and disconnects dial tone from
the speech path. If the processor determines that the digit is valid but does not
completely define a number it stores the digit in RAM. If the digit is invalid NU tone is
connected to the speech path. A valid extension number causes the processor to disconnect
the receiver and to connect a tone generator to provide ringing tone to the originating
extension. If the called extension is busy then busy tone is connected to the speech path.
Operator Console Dialling An Internal Number
The console keypad signals are recognised by a console microprocessor which examines
associated ROM to identify an 8 bit code particular to the depressed key. This code is
converted to serial data, with a start and stop bit and sent as a differential signal to
the console control ASU in the equipment cabinet. The serial data is converted to parallel
in the console control ASU. A data ready signal is presented on the IZ lead when the
scanner addresses the console control ASU. The processor determines whether the digit is
valid. For invalid digits NU tone is connected to the console speech path. If the digit is
valid but not a complete number it is stored in RAM. If the digit is valid and complete
the processor rings the extension and connects ringing tone back to the console.
Ringing An Extension
When the processor detects that a valid number is dialled it sends a command on the data
line to the address of the called extension which switches on ringing current. When the
extension answers the off hook signal is generated. Then processor disconnects ringing
current and connects the called extension through to the speech path used by the calling
The recall signal is detected by the extension ASU. The processor disconnects the
extension from its speech path, finds a free speech path, tests it, and then connects the
new speech path to the extension. A receiver and recall dial tone are connected to the new
speech path and the extension is then able to dial other extensions or facilities. The
other party of a call is connected by the processor to a 600 2 termination.
The exchange line ASU detects incoming ringing current. A microprocessor on the exchange
line ASU interrupts the system processor via the IZ lead/scanner procedure and illuminates
the exchange line LED on the front of the exchange line ASU. The system processor finds
and tests a free speech path and notifies the programmed answering equipment (console or
extension). When the call is answered the system processor connects the exchange line and
answering equipment to the speech path. A command is sent to the exchange line ASU to
terminate the trunk circuit and enable speech.
Dialling An Exchange Line From An Extension
An extension originating a call receives dial tone as described in 7.3. If the extension
then dials the code for an exchange line the processor interrogates the exchange line ASUs
to find a free circuit in the exchange line group. A data line seize command is sent to
the selected exchange line microprocessor and the exchange line is connected to the speech
path. The exchange line ASU connects an earth calling signal to the service exchange and
waits for an acknowledgement signal. The exchange line processor enables the audio and
illuminates the LED on the exchange line ASU. Serving exchange dial tone is received at
10 pps Extension Dialling Out
The subsequent dial pulses from the extension are repeated by a relay on the exchange line
ASU and are extended to the exchange line. Unless discriminatory call barring is specified
the receiver is disconnected when the exchange line access code is detected.
SSMF4 Extension Dialling Out
SSMF4 tones are translated by the receiver to digital data and passed to the system
processor. The system processor adds further data and passes the information to the
exchange line ASU processor. The exchange line ASU processor converts the data into a 10
pps pulse train onto the exchange line. The receiver is released when dialling is
Operator Console Dialling Out
The console keypad produces digital signals which are stored by the console
microprocessor. After an exchange line access code has been dialled the subsequently keyed
data signals are forwarded to the system microprocessor for decoding and then on to the
exchange line ASU for pulsing out on the exchange line. A receiver ASU is not used.
Operator Console Data Updating
All LEDS, including 7 segment displays on the operator console are refreshed or updated
under the control of the generic software program every 100 ms. The status of each display
element is maintained in RAM on the RAM/COS ASU. Every 100 ms, the system processor
addresses the RAM on the console control ASU and sends it 64 bytes of information for each
of the 2 consoles. This data is converted to serial form and forwarded to the console. In
the console, the information is transformed to parallel data and stored in RAM. The
console processor takes control of the information and sorts the data into a form required
to turn on or off the LEDS. The console audible tone calling device is also controlled by
On the backplane
wires on Connector TB1
Orange = +8v dc
Violet = -10v dc
Yellow = -5v dc
Brown = 0v
wires on Connector TB2
Grey = 90v ac
brown = earth
Blue = -50v dc
TB1 is top left
TB2 is bottom left
1 - -10v
2 - -5v
3 - 0v
4 - +8v
5 - +8v
1 - n/c
2 - 90v ac
4 - earth
5 - -50v
On the Emergency switching card
Located at the bottom inside rear left hand side.
1 - n/c
2 - Yellow - -5v
3 - Brown - 0v
4 - Orange - +8v
5 - Blue - -50v
6 - White/Blue
7 - Red
PSU terminal TB3
Numbered top to bottom
1 - batt
2 - 64v dc
3 - 0v
4 - -50v
5 - 75v ac
6 - 0v
Check with reference to the earth lug on the
1 & 2 are linked and so is 7 & 8.
Description Part No
1 SHELF CABINET (SX100) 9110-001-003-BA
2 SHELF CABINET (SX200) 9110-012-000-NA
IPC GEN 345 9110-203-345-NA
SCANNER CARD 9110-104-000-NA
TONE CONTROL CARD 9110-005-002-BT
CONSOLE CONTROL CARD 9110-006-000-NA
REC CARD QUAD 9110-016-005-BT
EXCH LINE CARD 4 CCT 9110-311-011-BT
EXTN LINE CARD 8 CCT 9110-310-000-BT
E+M 2 CCT CARD 9110-313-001-BT
AC15 2 CCT CARD 9110-113-000-BT
RECEIVER CARD DUAL 9110-003-001-BT
AC13 2 CCT CARD 9110-213-002-BT
SCDC CONVERTER 9110-065-000-BA
CONSOLE J/F BOARD 9110-045-000-NA
STANDBY POWER 9110-014-002-BT
IPC GEN 247 9110-203-247-BT
E&M TRK CARD 9110-013-002-BT
EQUIP SHELF 9110-012-003-BA
VHOC KIT (SX100) 9110-070-000-BT
PS UNIT 240V 9110-308-000-BT
POWER FAIL TRANSFER 9110-023-000-BT
INTERCOM CARD 9110-124-000-BT
AC15 TRUNK CARD (G48) 9110-113-002-BT
AC13 TRUNK CARD 9110-213-000-BT
SUPERSET EXT CARD 9110-410-001-BT
TIE TRUNK CARD 9110-031-000-BT
INT CONNECT CABLE 9110-026-000-NA
Meter Pulse CD 12CCT 8170-000-000-BA
IPC GENERIC 250 9110-203-250-NA
RECORDED ANNOUNCEMENT CARD 9110-072-001-NA
PCB CONSOLE INTERFACE 9110-145-000-NA
PCB POWER FAIL TRANSFER 9110-308-000-NA
In the case of G345 IPC Card faults, GENERIC 247 IPC Card may be
used as a replacement.