Lanex TM-81.1 User manual

IOA81-1E
August 2004
LANEX S.A., 8 Ceramiczna St., 20-150 Lublin, POLAND Service Dept.: tel. [phone]
MULTIPLEXER
Type
TM-81.1
5 X RS-232, 485 + 2 X ETHERNET
2 MBIT/S G.703 (G.704)
OPERATING MANUAL

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E I August 2004
Table of Contents
1GENERAL CHARACTERISTICS ............................................................................................................ 2
1.1 PURPOSE ............................................................................................................................................... 2
1.2 BASIC FEATURES OF THE UNIT.............................................................................................................. 2
1.3 EXAMPLES OF APPLICATION ................................................................................................................. 2
1.4 MARKING.............................................................................................................................................. 2
2CONNECTORS AND LED INDICATORS .............................................................................................. 2
2.1 FRONT PANEL ....................................................................................................................................... 2
2.2 REAR PANEL.......................................................................................................................................... 2
2.3 CONNECTORS' DATA ............................................................................................................................. 2
2.4 PRINCIPLES OF CONNECTING................................................................................................................. 2
E1 Interface.................................................................................................................................................... 2
Ethernet Interface .......................................................................................................................................... 2
RS-232/485 Interface ..................................................................................................................................... 2
3FUNCTIONAL DESCRIPTION ................................................................................................................ 2
3.1 INTRODUCTION ..................................................................................................................................... 2
3.2 BLOCK DIAGRAM .................................................................................................................................. 2
3.3 STRUCTURE OF 2048 KBIT/S SIGNAL FRAME ........................................................................................ 2
3.4 PRINCIPLES OF DROPPING THE SLOTS FROM 2048 KBIT/S SIGNAL.......................................................... 2
3.5 SELECTION OF OF TIME SLOTS ............................................................................................................... 2
3.6 SELECTION AND CONFIGURATION OF TRIBUTARY CHANNELS .............................................................. 2
3.7 OPERATING MODES OF TRIBUTARY CHANNELS .................................................................................... 2
Operating mode with interrupted transmission path ..................................................................................... 2
Operating mode without interrupting the transission path ............................................................................ 2
3.8 EMERGENCY MODE............................................................................................................................... 2
3.9 OPERATION WITH THE TM-48 DEVICE .................................................................................................. 2
3.10 OPERATION AS A TERMINAL EQUIPMENT .............................................................................................. 2
3.11 ESTABLISHING THE CLOCK SOURCE...................................................................................................... 2
............................................................................................................................................................................ 2
4INSTALLATION AND OPERATION ......................................................................................................2
4.1 INTRODUCTION ..................................................................................................................................... 2
4.2 OPERATING CONDITIONS ...................................................................................................................... 2
4.3 INSTALLATION ...................................................................................................................................... 2
4.4 SELECTION OF INPUT AND OUTPUT IMPEDANCE OF LINE PORTS ........................................................... 2
4.5 CONFIGURING THE CONTACT POINTS OF RS-232/485 CHANNEL PORTS ............................................... 2
4.6 POWER SUPPLY ..................................................................................................................................... 2
Mains ............................................................................................................................................................. 2
Power pack .................................................................................................................................................... 2
5CONFIGURATION..................................................................................................................................... 2
5.1 CONFIGURATION OF TRIBUTARY CHANNELS......................................................................................... 2
5.2 SELECTION OF DIRECTION IN TRIBUTARY CHANNELS ........................................................................... 2
5.3 SELECTION OF TIME SLOTS ................................................................................................................... 2
5.4 SELECTION OF OPERATING MODES FOR CHANNELS .............................................................................. 2
5.5 SELECTON OF OPERATING MODE FOR THE DEVICE ............................................................................... 2
6DIAGNOSTIC LOOPS ............................................................................................................................... 2
6.1 TRIBUTARY LOOP ON THE PORT "A"..................................................................................................... 2
6.2 TRIBUTARY LOOP ON THE PORT "B" ..................................................................................................... 2
6.3 TRIBUTARY LOOP ON "A" AND "B" PORTS ........................................................................................... 2
7DISTRIBUTION FRAME .......................................................................................................................... 2

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E II August 2004
8SPECIFICATIONS......................................................................................................................................2
8.1 ELECTRICAL PARAMETERS ....................................................................................................................2
2048 kbit/s Line Interface...............................................................................................................................2
RS-232(V.28) Asynchronous Digital Interface...............................................................................................2
RS-485(EIA-485) Asynchronous Digital Inteface ..........................................................................................2
Ethernet 10BASE-T Digital Interface.............................................................................................................2
8.2 MECHANICAL PARAMETERS ..................................................................................................................2
8.3 ELECTROMAGNETIC COMPATIBILITY ....................................................................................................2
8.4 ENVIRONMENTAL REQUIREMENTS........................................................................................................2
Operation .......................................................................................................................................................2
Transportation ...............................................................................................................................................2
Storage ...........................................................................................................................................................2
8.5 POWER SUPPLY .....................................................................................................................................2
9SCOPE OF DELIVERY..............................................................................................................................2

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E III August 2004
List of Abbreviations
AIS Alarm Indication Signal
ETSI European Telecommunications Standards Institute
GND Neutral (Ground)
ITU-T International Telecommunication Union – Telecommunication Standardization Sector
LOS Loss Of Signal
LOF Loss Of Frame
DCE Data Communication Equipment
DTE Data Terminal Equipment
SDH Synchronous Digital Hierarchy

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E IV August 2004
Operational safety
The TM-81.1 multiplexer has been designed and tested for the operating safety in
accordance with PN-EN 60950 standard.
!This Operating Manual is an integral part of the device and it is delivered to the Us-
ers along with it.
!Only authorised persons with qualifications confirmed by the appropriate certificate
can configure the device.
!The power supply cable should always be connected to power source by means of a
socket with neutral pin. Connection to the power network without neutral pin is al-
lowed, provided the earthing terminal located on the rear panel of the device is con-
nected to ground.
!Simultaneous grounding and neutral earthing through power cord is not allowed.
!Dual fuse - phase/neutral. Each phase wire is protected with separate fuse installed
inside the device. If only one fuse is defective, other components can be live.
!Some of power pack components installed on PCB are connected with mains potential.
!In order to avoid any contact with live components, always disconnect power supply
before removing the cover.
!The device is not equipped with a built-in circuit-breaking system. Such a system
should be installed outside the device.
The Manufacturer is not responsible for any use of the device in a manner non-
compliant with the operating manual.

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E 1 August 2004
1 General characteristics
1.1 Purpose
The device allows transmitting both asynchronous digital signals and Ethernet signals
through 64 kbit/s transmission channels of 2048 kbit/s stream structured in compliance with
ITU-T G.704 Recommendation.
The multiplexer is equipped with two 2048 kbit/s line ports that are compliant with ITU-
T G.703 recommendation in the physical layer. These ports enable connection with other tele-
communication devices like SDH or PCM-30 terminal equipment or any other signal sources
featuring the bitrate of 2048 kbit/s and equipped with corresponding interfaces.
The multiplexer enables adding the component 64 kbit/s signals to and dropping them
from a line stream of 2048 kbit/s, both in point-to-point or bus configuration.
1.2 Basic Features of the Unit
The unit is equipped with two line ports 2048 kbit/s compliant with ITU-T G.703 and
G.704 Recommendations.
Moreover, the multiplexer has five tributary ports compliant with ITU-T V.28 and V.11
standard, as well as two ports compliant with IEEE802.3 10BASE-T standard.
The device is available in two versions: powered from the 24 ÷50 V DC battery pack and
with power supply from 110÷230 V mains.
The multiplexer housing is 434 mm wide, 188 mm deep and 44 mm high. The front panel
of the device is equipped with the set of switches for device configuration and eleven LED
diodes that signal the device status.
It is possible to screw mounting brackets to the housing. These brackets are necessary for
mounting the device in a 19’’ or 21’’ telecommunication rack.

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E 2 August 2004
1.3 Examples of Application
G.703/G.704
G.703/G.704
C1 (RS232/485)
C6 (10BASE-T)
Radio line modem
Radio tower
TM-81
G.703/G.704
C6(10BASE-T)
TM-81
G.703/G.704
G.703/G.704
LAN
C7 (10BASE-T)
G.703/G.704
LAN
Managing station
C1-5 (RS232/485)
Telecommunication
network
TM-81 C2
(RS232/485)
Alarm
switchboard
C5
(RS232/485)
Alarm
switchboard
. . .
LAN
C7 (10BASE-T)
Fig. 1. Application of TM-81-1 multiplexer for construction of data transmission
and management networks.

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E 3 August 2004
G.703/G.704
G.703/G.704
C6
(10BASE-T)
TM-81
G.703/G.704
TM-81
TM-81
G.703/G.704
G.703/G.704
C7
(10BASE-T)
G.703/G.704
Monitoring station
C1-5 (RS232/485)
Telecommunication
network
C3-5
(RS232/485)
Alarm
switchboards
C3-5
(RS232/485)
C1
(RS232)
C2
(RS232)
IP camera IP camera
C6
(10BASE-T)
C7
(10BASE-T)
C1
(RS232)
C2
(RS232)
IP camera IP camera
C7
(10BASE-T)
C7
(10BASE-T)
Alarm
switchboards
Fig. 2. Application of TM-81.1 multiplexers for construction of object protection
networks

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E 4 August 2004
1.4 Marking
Note: Each time a symbol containing the letter "X" instead of its corresponding digit appears
in the Manual, it means that the feature specified in this part of the symbol is insignifi-
cant for the parameter being discussed and may be equal to any value from the above-
mentioned range. However, the device symbol specified for ordering purposes must
contain only the digits following the manufacturer symbol "TM".
2 Connectors and LED indicators
2.1 Front Panel
The following controls are located on the front panel of the device:
• Switches for configuring the device,
• LEDs for signalling the status of G.703 and 10BASE-T channels,
• LED for signalling the power on.
1 - Power On LED
2 - Switches for configuration of RS component channels
3 - Switches for configuration of ETHERNET component channels,
Status signalling for Ethernet channels (RCV- reception of frames at the port, LNK – informs whether
the port is connected correctly)
4 - Switches for configuration of E1 2048 kbit/s channels
5 - Status signalling for E1 ports
TM-81
MULTIPLEXER 7x64k/2M
T R I B U T A R Y C H A N N E L C O N F I G U R A T I O N
TM-81
B
A
A
IS
10
-3
LOF
LOS
G.703
CONFIGURATION
B
A
Droop
LNK
RCV
LNK
RCV
C CCCC C C LP CCCTS C 1 1134 5 7 7 762
CHANNEL DIRECTION
10BASE-T MODE OF OPERATION
45678123
ON
45678123
ON
4123
ON
45678123
ON
45678123
ON
45678123
ON
45678123
ON
45678123
ON
45678123
ON
910
RS232/485
Continue
Droop &
1 2 3 4 5
Fig. 3. Front panel

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E 5 August 2004
2.2 Rear panel
The following controls are located on the rear panel of the device:
• E1 interface connectors,
• Alarm contact connector,
• Connectors of RS-232, 485, and Ethernet 10BASE-T tributary channels,
• LEDs for signalling the status of 10BASE-T interfaces (LNK,RCV),
• Screw terminal for connecting the 48 V DC power supply,
• Grounding terminal.
POWER
LNK LNK
RCV RCV
10BASE-T 10BASE-T
2x10BASE-T5xRS232/485
MDI-XDCE
C 24
CCCCC 13567
BA
75W
120W
Alarm
7,8 SHIELD
51
96
1 2 3 4 5 6
1 - Connectors of E1 interfaces – balanced 120 ΩDB-9, coaxial 75 Ω1,6/5,6 mm
2 - Screw terminal for alarm contact
3 - Connectors of RS-232, 485 tributary chatnnels:
C1 – first tributary channel, etc.
4 - Connectors of Ethernet – RJ-45 tributary channels
Status signalling for Ethernet channels (RCV- reception of frames at the port, LNK – informs whether the
port is connected correctly)
5 - Screw terminal for power supply
6 - Grounding terminal
Fig. 4. Rear panel

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
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2.3 Connectors’ data
Pin No. Pin Description
1,6 Transmission of Data – output
5,9 Reception of Data – input
7 Transmitted data – shield
1
6
5
9
87
8 Received data – shield
Fig. 5. View and description of balanced E1/G.703 120 Ωcontact connector
Pin No. Pin Description
1 DCD
2 RD (Transmitted Data)
3 TD (Received Data)
4 DTR
5 GND
6 DSR
7 RTS
8 CTS
1
6
5
9
9 Not connected
Fig. 6. View and description of asynchronous RS-232 DCE interface connector
Pin No. Pin Description
1 Not connected
2 TD+ (Transmitted data)
3 RD+ (Received data)
4 Not connected
5 Not connected
6 TD- (Transmitted data)
7 Not connected
8 RD- (Received data)
1
6
5
9
9 Not connected
Fig. 7. View and description of asynchronous RS-485 interface connector
Pin No. Pin Description
1 TD+( Received data)
2 TD- (Received data)
3 RD+(Transmitted data)
18
6 RD- (Transmitted data)
Fig. 8. View and description of Ethernet - MDI-X interface connector

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E 7 August 2004
2.4 Principles of Connecting
E1 Interface
Input and output signals of the E1/G.703 interface can be fed in two ways:
• By using two coaxial cables with the impedance of 75 Ω, terminated with 1,6/5,6 plug-in
connectors, or
• By using two screened balanced cables with the impedance of 120 Ω, or one screened
double cable with the same impedance.
Please remember to set jumpers inside the device in accordance with the type of cable
used – see point 4.4.
To meet the requirements concerning generation of radioelectric interference, the follow-
ing principles should be observed:
• The 1,6/5,6 plug-in connector should be installed on the coaxial cable in the way ensuring
the good electric contact of the cable screen with the housing of connector around the
whole periphery,
• Connection of balanced cables should be made by using the DB-9 plug-in connector
equipped with metallic or metallised housing (casing), and the screen of cable/cables
should contact the housing around the whole periphery.
Description of pins in the E1/G.703 120 Ωinterface socket is given in the point 2.3.
The Ethernet Interface
Pin1
Pin8
1 White/orange
2 Orange
3 White/green
4 White/blue
5 Blue
6 Green
7 White/brown
8 Brown
1 White/green
2 Green
3 White/orange
4 White/blue
5 Blue
6 Orange
7 White/brown
8 Brown
Fig. 9. View of the cable for connecting the Ethernet port of the TM-81.1 multiplexer
with the MDI-X port of the connected device.
Pin1
Pin8
1 White/orange
2 Orange
3 White/green
4 White/blue
5 Blue
6 Green
7 White/brown
8 Brown
1 White/orange
2 Orange
3 White/green
4 White/blue
5 Blue
6 Green
7 White/brown
8 Brown
Fig. 10. View of the cable for connecting the Ethernet port of the TM-81.1 multiplexer
with the MDI port of the connected device.

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E 8 August 2004
The TM-81.1 device is equipped with two Ethernet 10BASE-T MDI-X tributary ports
outputted to RJ-45 connectors.
The cables connecting the TM-81.1 multiplexer with other devices are shown on Fig. 9
and 10. When connecting with the MDI-X port of other device (like hub or switch) the pairs
of transmitter and receiver should be crossed (Fig, No. 9). For connecting with the MDI port
(network card, router) pairs of transmitter and receiver should be connected directly (Fig. No.
10).
Connection should be made by twisted cable, category 5 at least, with the characteristic
impedance of 100 Ω.
The RS-232/485 Interface
The device is equipped with five asynchronous DCE ports outputted to DB-9 connectors
located at rear panel. Each port may be configured for connection with the RS-232 or RS-485
interface. Type of connected interface is selectable by using switches that are individually
dedicated to each port and located on the front panel.
Scheme of connecting the RS-232 interface cable depends on pin arrangement and type
of mating connector. Correct operation is ensured on condition that suitable circuits are con-
nected and the transmitter →receiver principle is observed during connecting the port with
another interface.
When configuring the interface to RS-485, a number of operations, resulting from the in-
terface properties, should be performed in order to ensure proper operation of the interface.
When switching to another type of interface, the type of transmitters and receivers change
from unbalanced RS-232 to balanced RS-485 ones. Therefore the RS-485 interface should be
connected by using twisted cable with the characteristic impedance of pairs equal to 120 Ω.
Also, the principle of connecting +/- circuits with the same symbol (e.g. TD+/-) over one pair
should be observed.
As a standard, a RS-485 line uses a shielded balanced twisted cable for transmitting the
signals. Up to 32 receivers/transmitters can be connected to balanced twisted bus. There are
no special recommendations concerning the point where the device is connected to the bus
and connecting the device at the end is not necessary, however the resistors with impedance
equal to characteristic impedance of cable should be connected to at both ends of the bus.
Due to specific nature of RS-485 topology, transmitters are required to set into high im-
pedance state after completion of transmission or during no-transmission period. This state is
seen by receiver as silence on the line. Most line receivers set into logical 1 when their inputs
are open. In case of no transmission all transmitters are set to high impedance and their inputs
are short-circuited by 120 Ωresistors. From the receiver point of view such state is undefined
and, despite the use of hysteresis in receivers, occurrence of interferences on the line may
cause switching of the receiver. In order to prevent this phenomenon, the line during no-
transmission is enforcedly set to appropriate state by adequate biasing of receiver’s inputs.
Each port of the TM-81.1 multiplexer is equipped with a set of resistors allowing terminat-
ing the bus. These resistors are connectable by using a set of jumpers described in point 4.5.

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E 9 August 2004
Attaching the terminating resistor simultaneously induces line bias as shown below.
Fig. 11. TM-81.1 multiplexer - connecting of terminating resistor and biasing the line.
Each port of the TM-81.1 multiplexer, once configured for RS-485, can work in two
modes of transmission, i.e. half-duplex or duplex mode. Setting the operating mode up is
possible by using a set of configuration switches located on the front panel of the device.
When the device is to work in half-duplex mode and transmit through one twisted
pair, it is necessary to short the circuits RD+ →TD+ and RD- →TD- on the cable at-
tached to the multiplexer.
RD+RD-
Ground Vcc

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E 10 August 2004
3 Functional Description
3.1 Introduction
The multiplexer is equipped with two 2048 kbit/s line ports (A and B) compliant with
ITU-T G.703 and G.704 recommendations. Through these ports the device can be connected
with other telecommunication devices like SDH multiplexers, PCM-30 multiplexers or with
any other signal sources featuring with the bitrate of 2048 kbit/s and equipped with similar
interfaces.
Next, the multiplexer is equipped with five full-duplex channel ports C1÷C5 compliant
with the ITU-T V.28 or EIA-485 standard and two duplex channel ports C6÷C7 compliant
with IEE802.3 10BASE-T standard in the physical layer, allowing connecting the device with
telecommunication equipment with identical interfaces. These ports are also called „tributary
channels”.
The fundamental function of multiplexer is to transmit signals appearing in C1÷C7 tribu-
tary channels through 64 kbit/s time slots of 2048 kbit/s stream introduced by one of line
ports. A data signal delivered to channel ports is directed to physical input transceivers, re-
generated and then delivered to asynchronous/synchronous controllers.
The access of tributary channels to the 2048 kbit/s stream is possible thanks to the inte-
gral, configurable dropping circuit (see Fig. 12).
The dropping circuit can be configured by using a set of switches located at the front
panel. When configuring this circuit, it is possible to:
- Select tributary channels designated for transmission;
- Select the group of time slots within the 2048 kbit/s stream and assign this group to
tributary channels;
- Establish the line port (A or B) from which time slots will be dropped;
- Set operating mode for each tributary channel.
Detailed description of the configuration function and methods of dropping are given in next
sections of this manual.
C1 C2 C3 C4 C5 C6 C7
PORT
B
PORT
A
5 x RS-232/485 2 x 10BASE-T
TM-81
MULTIPLEXER 7x64k/2M
TRIBUTARY CHANNELCONFIGURAT ION
TM-81
B
A
A
IS
10
-3
LOF
LOS
G.703
CONFIGURATION
LNK
BOR
AMUX
RCV
C CCCC C C C CCC 1 1134 5 7 7 762
CHANNE L DI R ECTI ON MODE O F OP ER ATIO N
45678123
ON
45678123
ON
4123
ON
45678123
ON
45678123
ON
45678123
ON
45678123
ON
45678123
ON
45678123
ON
910
LNK
RCV
Fig. 12. Multiplexer type TM-81: transmission ports

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E 11 August 2004
3.2 Block Diagram
Relays
shunting the
device at
power failure
2048kbit/s
G.703
Circuit for dropping/inserting
time slots into/from signal
frame 2048kbit/s
Nadajnik/
odbiornik
RS-232
Transmitter/
Receiver
RS-232 RS-232 RS-232 RS-232 RS-232
Nadajnik/
odbiornik
RS-232
Nadajnik/
odbiornik
RS-232
Nadajnik/
odbiornik
RS-232
Nadajnik/
odbiornik
RS-232
Signal
transmitter
and receiver
2048kbit/s
G.703
LED signalling
diode
Alarm
relay
Signal
transmitter
and receiver
2048kbit/s
G.703
Micro-controller
Configuration
switches
Local(tributary) channel
Direction of channel
Channel operation mode
CONFIGURATION
Relays
shunting the
device at
power failure
Line port B
G.703 2048kbit/s
Line port A
G.703 2048kbit/s
Signal framing
synchronisation
circuit
2048kbit/s
G.703
Alarm
contact
Dwukierunkowe porty
kanałowe RS232(V.28)
C1-C10
Ethernet
PHY
&
Bridge
Ethernet
PHY
&
Bridge
Transmitter/
Receiver
Transmitter/
Receiver
Transmitter/
Receiver
Transmitter/
Receiver
Signal framing
synchronisation
circuit
Fig. 13. Block diagram

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E 12 August 2004
3.3 Structure of 2048 kbit/s signal frame
The frame of 2048 kbit/s signal, compliant with the ITU-T G.704 Recommendation, is
composed of 256 bits numbered from 1 to 256 and is repeated with the frequency of 8 kHz.
Successive bits: 1÷8, 9÷16, 17÷24, ..., and 249÷256 form 32 channels, 64 kbit/s each. These
channels are located in 32 time slots numbered from 0 to 31.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Fig. 14. Frame of the 2048 kbit/s signal
For transmission of digital signals only time slots 1 - 15 and 17 – 31 are used.
The slot 0 is used for transporting the frame synchronization pattern, service bits and
CRC-4 cyclic code remainder bits (if the generation option is set). The sixteenth slot dedi-
cated to signalling is not used.
The device allows setting the option of generation of CRC-4 code and multiframe syn-
chronisation signal. The device is factory configured in such a way that the remainder of
CRC-4 code and the pattern of multiframe synchronisation are not added to outgoing frame.
To enable the function of adding the remainder of CRC-4 code, it is necessary to short JP16
contacts on position 17 (Fig. 15), whereas adding the multiframe synchronisation pattern is
forced by shorting JP16 contacts on position 3. To activate these settings it is necessary to
restart the device or initialise it by momentary shorting the RESET contacts.
PMC
PMC
ALTERA
ATMEL
17 3 4 5
RESET
J16 P
Fig. 15. Jumpers for enabling generation of CRC-4 cyclic code and multiframe
synchronisation signal

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
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3.4 Principles of dropping the slots from 2048 kbit/s signal
Principles of dropping the slots from the 2048 kbit/s signal result from the frame struc-
ture. During dropping process the slots TS0 and TS16 are omitted. Assuming that the TS(x)
slot is the first timeslot designated for transmitting signals of n tributary channels, where
x∈(1÷15, 17÷31), n∈(1÷7), and:
- if x≤15 and x+(n–1)≤15, then slots from TS(x) up to TS(x+n-1) will be dropped (Fig. 16a),
- if x≥17 and x+(n-1) ≤31, then slots from TS(x) up to TS(x+n-1) will be dropped (Fig. 16b),
- if x≤15 and x+(n-1)≥16, then slots from TS(x) up to TS15 and from TS17 up to TS(x+n) will
be dropped (Fig. 16c), and
- if x+(n-1)>31, then slots from TS(x) up to TS31 and from TS1 up to TS(x+n-32) will be
dropped (Fig. 16d).
a)
0 ••••• • •16
↑ ↑
TS(x) TS(x+n-1)
b)
0 16
•••••••
↑ ↑
TS(x) TS(x+n-1)
c)
0
• • • • 16 • • •
↑
↑
TS(x) TS(x+n)
d)
0 ••• 16
• • • •
↑↑
TS(x+n-32) TS(x)
Fig. 16. Dropping of 64 kbit/s slots from 2048 kbit/s signal frame

5 X RS-232,485 + 2 X ETHERNET /2 MBIT/S G.703 (G.704) MULTIPLEXER
OPERATING MANUAL
IOA81-1E 14 August 2004
3.5 Selection of time slots
Assignment of time slots TS of the 2048 kbit/s stream to tributary channels is made by
using „CONFIGURATION” switches. Assignment is effected by selecting the number of first
slot from the group of slots intended for transmission.
The selected group of slots is associated with the C1÷C7 tributary channels in such a way
that first tributary channel C1 is assigned to the first slot of the 2048 kbit/s stream, and next
tributary channels C2 – C7 are assigned to next successive slots.
When selecting timeslot it is important to remember that:
• neither TS0 nor TS16 slots can be selected as a first slot,
• the TS0 and TS16 slots are not assignable, in compliance with principles described in
point 3.4.
In examples shown below the slot number 2 is selected, i.e. the group of slots 2÷9 is de-
signed for transmission.
Selected timeslots are associated with tributary channels, but these channels do not occupy
them. Slots are occupied when specified tributary channels are switched on by switches that
configure the working parameters of tributary channels.
3.6 Selection and configuration of tributary channels
Switching on and configuring of C1÷C7 channels, i.e. occupying the selected timeslots, is
possible by using the „TRIBUTARY CHANNEL CONFIGURATION” switches, whereas the
„CHANNEL DIRECTION” switches allow setting, for every channel, from which line port
(A or B) the time slots will be dropped.
Switches on front panel
Initial slot selected by using
CONFIGURATION switches
Input of line
port B
Output of line
port A
Output of
line port B
Input of line
port A
CHANNEL DIRECTION
TRIBUTARY CHANNEL
CONFIGURATION
Selected group of timeslots
. . .
. . .
. . .
. . .
. . .
Selected group of timeslots
A
B
C1-5
C6-7
Fig. 17. Dropping of 64 kbit/s slots from the 2048 kbit/s signal frame