Black Box Echo Series User manual

Echo 2 Mbps Multiplexer
Jan 97 / Version 1.1
TECHNICAL:
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FAX:
ADDRESS:
WEB:
[phone]
[phone]
[phone]
464 Basingstoke Road, Reading, Berkshire RG2 0QN
www.blackbox.co.uk
Echo Mux X.21/V.11:
MXU9070
Echo Mux V.35:
MXU9076

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ECHO
E1 2 Megabit Multiplexer range
User Manual
WARNING - BEFORE INSTALLATION, PLEASE REFER
TO SAFETY INSTRUCTIONS IN APPENDIX A, AND
EMC INSTRUCTIONS IN APPENDIX C
Certified Compliant in the EC, when fitted in accordance with the installation instructions,
against the following directives/standards:
Low Voltage Directive (73/23/EEC and amendment 93/68/EEC)
EN60950 : 1992 (Safety)
Electromagnetic Compatibility directive (89/336/EEC and subsequent
amendments to date):
EN55022 : 1994 (Emissions)
EN50082-1 : 1992 (Immunity)
Telecommunications Terminal Equipment directive (91/263/EEC and
amendment 93/68/EEC) where indicated in approvals requirements section.

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Contents
Introduction..............................................................................................................................................6
Functional overview....................................................................................................................6
Typical Applications....................................................................................................................7
Use and Configuration.............................................................................................................................9
Data Channel Connection...........................................................................................................9
Default Channel Setup................................................................................................................9
Changing the Configuration........................................................................................................9
Supervisor Terminal requirements..............................................................................................9
Supervisor Terminal Emulations...............................................................................................10
General Set-Up Display Layout.................................................................................................11
General Keyboard Conventions................................................................................................11
Cursor Movement........................................................................................................12
Parameter changing.....................................................................................................12
Accepting allchangesand Updating the configuration ................................................12
Abandoning Changes..................................................................................................12
Local or Remote Configuration....................................................................................12
Changing the configuration page.................................................................................12
Nx64 channel Configuration......................................................................................................13
Timeslot Assignment.................................................................................................................13
Drop and Insert (D&I) channel operation...................................................................................15
Setting the System's Real-Time Clock......................................................................................16
Viewing the Statistics pages.....................................................................................................16
Viewing the Event Log..............................................................................................................17
Clearing the EventLog .............................................................................................................18
System Alarms & Alarm port.....................................................................................................18
Link Carrier Loss..........................................................................................................19
Timeslot Mismatch.......................................................................................................20
D&I Carrier Loss..........................................................................................................20
D&I Remote Alarm.......................................................................................................20
Nx64 Control Off..........................................................................................................20
Nx64 Clock Fail............................................................................................................20
Remote Alarm..............................................................................................................20
Link BER High..............................................................................................................21
Echo Multiplexer Installation..................................................................................................................22
Supply Voltage & Connection...................................................................................................22
Environmental Considerations..................................................................................................22
Mechanical Construction...........................................................................................................22
Composite Interface Selection..................................................................................................23
Composite Network Connection................................................................................................23

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Composite Link Parameters......................................................................................................24
Back to Back demonstration connection...................................................................................25
Internal Clock (other site in loop).................................................................................25
Using an external Clock reference............................................................................................26
External Channel Clock...............................................................................................26
External Reference Clock............................................................................................26
Through Clock (Master fromD&I link)..........................................................................27
Troubleshooting.....................................................................................................................................28
Front Panel LEDs......................................................................................................................28
Diagnostics & Loopbacks..........................................................................................................29
Appendix A - Warnings..........................................................................................................................30
Appendix B - Approval...........................................................................................................................33
Appendix C - EMC Requirements..........................................................................................................34
Limitation of Emissions:............................................................................................................34
'D-Type' Connections...................................................................................................34
Mains Connection........................................................................................................35
To Ensure thatadequate immunity is achieved:.......................................................................35
Appendix D – Rear Panel Lay Out.........................................................................................................36
Appendix E - Supervisor Port Pinout......................................................................................................37
Appendix F - Composite InterfacePinouts............................................................................................38
Appendix G - RJ45E1 Crossover Cable................................................................................................40
Appendix H - X.21/V.11 Data ChannelPinout........................................................................................41
Appendix I - X.21/V.11 Network Crossover Cable .................................................................................42
Appendix J - Alarms...............................................................................................................................43
Appendix K - Echo Technical Specification............................................................................................44

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Introduction
The Echo is an E1 time division multiplexer, operating at 2.048 Mbps, supporting up to 4
X.21/V.11 data channels, and an additional (optional) E1 drop and insert link.
The unit is easily configured from either end of the link, using a terminal or a PC running a
terminal emulation package.
This user manual covers installation and setup of user options for the multiplexer. A full set
of cable diagrams is available in the appendices.
Functional overview
The ECHO E1 multiplexer is a time division multiplexer operating at 2.048 Mbps, compliant
with both EUROPEAN and UK G.703 standards.
The composite link is interface selectable for either UK (75 Ohms un-balanced) or
EUROPEAN (120 Ohms balanced).
Up to 4 synchronous data ports are supported, operating at data rates of up to 1984Kbps, in
64Kbps steps. The channel data rates are set by time slot allocation (which need not be
contiguous).
A drop and insert (D&I) option card allows an additional E1 link, for connection of a
PABX. Time slots not used by the D&I channel made available for use on any of the data
channels.

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Typical Applications
The Echo may be used to provide up to 4 Nx64K X.21/V.11 channel connections (at any
multiple of 64K) between two sites, using a G.703 2 Megabit/Second data link, as shown
below:

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It is also possible to connect two systems back to back directly in this manner, using an
appropriate cable. This configuration is described on page 25.
Where the Echo is to be used to provide unused PABX (or bridge) bandwidth to Nx64
X.21/V.11 ports, the optional Drop and Insert card is used as follows:
The Echo is set so that the slots used by the PABX are passed through to the main G.703 link
transparently. This is described on page 15. The remaining unused timeslots can now be
assigned as required to the channel ports.
The connection between the D&I port and the PABX will need to be crossed over using the
appropriate cable arrangement (same as the back to back Demo cable) shown on page 25.

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Use and Configuration
This section covers connection and set-up of the channel data ports. The composite port is
covered in the installation section of this manual.
Data Channel Connection
Peripherals are connected to the X.21/V.11 15 way 'D'-type connectors configured DCE and
numbered 1 to 4 at the rear of the multiplexer. The pin connections for these data channels
are defined in Appendix H.
Default Channel Setup
When delivered or factory reset, the Echo Time Division Multiplexer is set to operate with all
channels set as follows:
Rate :Off
Mode :NORMAL
TX Clock : INT
RX Clock : INT
Indicate : ON
Changing the Configuration
The Echo may be configured using an asynchronous terminal. A laptop PC running an
asynchronous terminal emulation program such as PCAnywhere, CrossTalkor Windows
Terminalis ideal for the field engineer. The terminal should be connected via its serial port
to the SUPERVISOR port on the rear of the multiplexer.
Supervisor Terminal requirements
The terminal must be configured to:
8 bit character, no parity, one stop bit, speed 9.6Kbps
A suitable cable for connection of the Supervisor port is defined in Appendix E.

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Supervisor Terminal Emulations
Several terminal emulations are supported by the Echo. When connection is made between
the terminal or PC and the rear panel port labelled SUPERVISOR, the following screen will
appear:
The terminal type or emulation in use should be selected by pressing the relevant number key
on the PC or terminal. The monitor will now show the basic configuration screen for the
multiplexer setup. This is formatted as below:
Please select terminal type from the following:
1 = VT52
2 = VT100
3 = ADDSVP
4 = ADM3A
5 = H1500
6 = N8009
7 = TVI920
2MEGABIT E1 MULTIPLEXER V1.00
=============================== 15:35 16/09/96 ==================================
Main Link (EUR : SYNCHRONISED
Mode : NORMAL * Nx64 Channels : 4
Framing : CRC4 D&I Channels : NOT FITTED
Idle Bandwidth : 1344K System Alarms : None
ClockReference : INTERNAL Statistics : Error Counts
Configuration : >LOCAL Events : Log
Nx64 Channel : 1 2 3 4
Rate : 384K 256K OFF OFF
Mode : NORMAL NORMAL NORMAL NORMAL
TX Clock : INT EXT INT INT
RX Clock : INT EXT INT INT
Indicate : ON ON ON ON
Control : ON ON ON ON
-----------------------TIMESLOTMAP--------------------------
0 0 00 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 2 2 2 2 22 2 2 2 2 3 3 3
0 1 23 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 34 5 6 7 8 9 0 1
---------------------------------------------------------------
R2 2 1 1 2 2 1 1 1 1 - - - - - - - - - - - -- - - - - - - - -
Cursor Keys to move, CTRL-U to save, ESC to abandon
=================================================================================
Use<SPACEBAR>/<+>/<-> to select

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General Set-Up Display Layout
There are three main areas on the supervisor set-up screen used to change parameters for the
Echo:
Upper left -
System parameters (Mode,
Clock Ref, Carrier, Idle
Bandwidth, and Configure etc.).
Upper right -
Other display pages which may
be selected, (Statistics etc.).
Bottom -
Channel configuration.
The initial display is that for the
Nx64 channels.
General Keyboard Conventions
Only a few keys are required to configure the Echo multiplexer and are summarised as
follows:
→(Right arrow) Moves the cursor to the next field to the right.
←(Left arrow) Moves the cursor to the next field to the left.
↑(Up arrow) Moves the cursor to the next field upwards.
↓(Down arrow) Moves the cursor to the next field downwards.
+ (Plus) or <SPACEBAR> Toggles the parameter value up to the next available setting.
- (Minus) Toggles the parameter value down to the next available setting.
<ENTER> or <RETURN> Accepts the current display page (else same as ↓).
<CTRL> and U Accepts all changes and causes multiplexer re-configuration.
<ESC> Abandons all changes since last <CTRL> and U.

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Cursor Movement
The cursor symbol ">" is moved around the screen to the required field using the arrow
keys.
Parameter changing
If it is possible to modify the field over which the cursor is placed, the message "Use
<SPACEBAR>, <+>, <->" is shown at the bottom of the screen. No message will appear if
the field is calculated, un-modifiable or hardware set.
Pressing the Space bar, the "+" key or the "-" key will cycle through the choices available for
a parameter.
Accepting all changes and Updating the configuration
If "Control" and "U" are pressed at the same time after the configuration has been suitably
adjusted, the configuration is updated at the local and remote end as necessary and held in
Non-Volatile Memory (NVRAM.)
Abandoning Changes
Pressing ESC at any point before a configuration is updated will cause the message Abandon
Changes? (y/n) to appear at the bottom of the screen. If nis selected the message will
disappear and editing may continue. If yis pressed, all modifications will be abandoned and
last updated configuration will be re-painted to the screen.
Local or Remote Configuration.
Most settings are independent at each end of the multiplexer link e.g. Clock Reference.
The "Configure" parameter in the upper left of the selected screen shows whether the
LOCAL or REMOTE multiplexer is being configured.
Changing the configuration page
The Configuration Page required, e.g. 'Channels', or 'Events' etc., is selected by moving the
cursor to the upper right area and pressing Enter when alongside the required page.

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Nx64 channel Configuration
To change the Nx64 channel configuration, select the configuration screen (shown on page
10) by moving the cursor to the top line on the right hand area of the screen, next to 'Nx64
Channels:' and pressing ENTER or RETURN.
The display shows parameters for up to four data channels CH1 to CH4.
Each data channel has parameters selectable as detailed in the table on the following page.
Timeslot Assignment
Timeslots are assigned by moving the cursor down to the Timeslot map section of the Nx64
Channels screen.
Timeslots may be assigned directly by pressing the appropriate key on the Supervisor port
terminal keyboard eg:
Pressing: 1 Assigns the slot to Nx64 Channel 1
2Assigns the slot to Nx64 Channel 2
3Assigns the slot to Nx64 Channel 3
4Assigns the slot to Nx64 Channel 4
DAssigns the slot to the D&I Channel (if fitted)
-Un-assigns the timeslot
Timeslots assigned to each channel will each contribute 64K of bandwidth. The Rate field
for the channel will automatically be updated to show the rate which the channel will be
running.
Note that if the D&I channel is connected to a PABX which is using timeslot 16 for
signalling or CCS signalling, timeslot 16 must be assigned to the D&I channel.
It is of course, very important to plan which timeslots are to be used by the connected PABX
and which are to be used for data channels. This will almost certainly require some setting up
of the PABX as well as the multiplexer.

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Echo Channel Set-up Options
PARAMETER CHOICES NOTES
Rate Off, 64K ... 1984K in 64K steps. Channel data rate (calculated
from time slot allocation set by
user).
Mode NORMAL Normal RUN mode.
LOOP Set this to enable bi-lateral
channel loopback.
TX Clock INT Clock is supplied by MUX to
device connected to channel
using S(A) and S(B) pins for TX
data.
EXT Clock is supplied by device
connected to channel port, using
X(A) and X(B) pins for TX data.
See note below.
RX Clock INT Clock is supplied by MUX to
device connected to channel
using S(A) and S(B) pins for RX
data.
EXT Clock is supplied by device
connected to channel port, using
X(A) and X(B) pins for RX
data. See note below.
Indicate ON Indicated pin permanently
asserted.
OFF Indicated pin permanently not
asserted.
TRANS Transparent mode.
Indicate pin asserted when
remote Control pin is asserted
(updated at approximately 10
times per second)
CARRIER Indicate pin asserted whenever
carrier is present.

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Note: If an external clock option is selected, unless the external device is
synchronised to the main link clock, clock slips will inevitably occur, leading to data
loss.
Drop and Insert (D&I) channel operation
The optional G.703 Drop and Insert channel allows connection of external G.703 equipment
(eg. PABX) which uses only part of the 2 megabit timeslot map. This is sometimes referred
to as 'Fractional E1'.
The timeslots are assigned as shown above for channels, using 'D' to select the D&I channel.
An additional menu page is available, allowing the Time Slot Map to be edited, whilst
showing the D&I channel settings.
The way in which the D&I channel synchronises as well as mode settings, are also set on this
page. For more details of these link settings see the main link parameter settings section
(page 24).
When the D&I card is fitted, it is also possible to slave the clock reference to the D&I
channel. This is achieved by selecting THROUGH as the Clock Reference as shown above.
2 MEGABITE1 MULTIPLEXER V1.00
=============================== 15:31 16/09/96 ==================================
Main Link (EUR) : SYNCHRONISED
Mode : NORMAL Nx64 Channels : 4
Framing : CRC4 * D&I Channels : 1
Idle Bandwidth : 320K System Alarms : Minor
Clock Reference : THROUGH Statistics : Error Counts
Configuration : LOCAL Events : Log
D&I Channel (EUR) : NO CARRIER
Drop Bandwidth : 1024K
Mode : NORMAL
Framing : CRC4
-----------------------TIMESLOTMAP--------------------------
0 0 00 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 2 2 2 2 22 2 2 2 2 3 3 3
0 1 23 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 34 5 6 7 8 9 0 1
---------------------------------------------------------------
R2 2 1 1 2 2 1 1 1 1 - - - - - DD D D D D D D D D D D DD D D
Cursor Keys to move, CTRL-U to save, ESC to abandon
=================================================================================
Use<SPACEBAR>/<+>/<-> to select

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Setting the System's Real-Time Clock
To change the system clock time, position the >cursor at the "Set Clock" field. The message
'Enter time and date (hh-mm-ss dd/mm/yy)' will appear at the bottom of the screen. The
time should be entered following the format shown. Time updates may be entered without a
date, but to change the date, both must be entered.
Viewing the Statistics pages
The Statistics pages give regularly updated information as to the performance of the E1 data
link(s).
It is important to note that there are in fact four statistics pages available for viewing:
m) Local Main Link
n) Local D&I Link (if fitted)
o) Remote Main Link
p) Remote D&I Link (if fitted)
These pages are accessed by moving the cursor to the 'Statistics :' field, using the spacebar to
select either the main link or the D&I link (if fitted). The local and remote pages are
accessed in the normal manner (using the spacebar on the 'Configuration' field).
2MEGABITE1MULTIPLEXER V1.01
=============================== 09:45 25/11/96 ==================================
Main Link (EUR) : SYNCHRONISED
Mode : NORMAL Nx64 Channels : 4
Framing : CRC4 D&I Channels : NOT FITTED
Idle Bandwidth : 1984K System Alarms : None
Clock Reference : INTERNAL * Statistics : Main Link
Configuration : LOCAL Events : Log
Error Counts: >PeriodEnd-----BVC------BER-------CRC------FEBE-------FAS------SYNC
14:33:00 2902 8.9E-06 506 362 94 2
14:48:00 0 <1E-09 0 0 0 0
15:03:00 0 <1E-09 0 0 0 0
15:18:00 0 <1E-09 0 0 0 0
15:33:00 0 <1E-09 0 0 0 0
Current: 15:36:40 0 <1E-09 0 0 0 0
Cursor Keys to move, CTRL-U to save, ESC to abandon
=================================================================================
(S)tart, (E)nd, (^R)eset current, <- / -> = scroll

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Each entry on a page represents a summary of link performance over 15 minutes of operation.
The Current entry, is updated every 10 seconds with any errors identified in the preceding
10 seconds.
To view additional entries not shown (if any) on the current screen page, move the cursor to
the 'Period end' field, and use the Left and Right arrow keys. This will scroll the statistics
information up or down by one page respectively.
For diagnostics purposes it is possible to Clear the Current line (ie start a fresh line), by
moving the cursor to the 'Period end' field, then typing <CTRL> and R. This is useful if the
operator wishes to check that a condition which may have been causing errors has been
removed.
On the screen display, the following abbreviations are used:
BVC = Bipolar Violation Count errors
BER = Approximate Bit Error Rate (based on BVC), which may be used
to trigger an alarm. Note that BER is only calculated when the
unit is in SYNC with the remote unit.
CRC = Cyclic Redundancy Check errors (in CRC4 mode only, otherwise
shown as '----')
FEBE = Far End Block Errors (in CRC4 mode only otherwise shown as '--
--')
FAS = Frame Alignment Signal losses
SYNC = Synchronisation losses (reported each time sync goes from
'present' to 'lost')
These statistics provide a very useful summary of link performance over the last 24 Hour
period.
Note that, unlike the event log, the statistics are not retained in the event of a power failure.
Viewing the Event Log
An event log is maintained which stores (in non-volatile memory) crucial events, such as
power up, alarms, and configuration change, and carrier loss times.
It is also possible to enable channel related events, (such as loss of external channel clock) to
be logged. These are enabled on the System Alarms page (see later).

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The event log is very useful for diagnosing fault conditions.
The kind of information which is included in the event log may be chosen by the user, by
selecting the Alarm Actions on the Alarm page, described in the section below.
Clearing the Event Log
The event log can be cleared by moving the cursor to the position on the screen where the
first event is shown (after 'Events :') and pressing <CTRL> and 'R' together. This will
delete all events from the list, and leave the message 'Event Log Cleared' as the only event.
It may be useful to clear the remote event log at the same time, by accessing the REMOTE
page, and repeating this process.
System Alarms & Alarm port
Two general purpose relay contact pairs are provided for use with the Echo. Separate
changeover contacts are provided, for both MAJOR and Minor Alarms. The contacts may be
connected to external low voltage (SELV) equipment to give an alarm / network management
indication as required. These connections are shown in Appendix J.
2 MEGABIT E1MULTIPLEXER V1.00
=============================== 15:45 16/09/96 ==================================
Main Link (EUR) : SYNCHRONISED
Mode : NORMAL Nx64 Channels : 4
Framing : CRC4 D&I Channels : NOT FITTED
Idle Bandwidth : 1344K System Alarms : None
Clock Reference : INTERNAL Statistics : Error Counts
Configuration : >LOCAL * Events : Log
Set Time :
Events : EV00001: 13:43 16/09/96 System Reset
EV00002: 13:43 16/09/96 Composite Sync gain
EV00003: 15:20 16/09/96 Composite Sync loss
EV00004: 15:22 16/09/96 Composite Sync gain
EV00005: 15:40 16/09/96 Nx64 Channel 2 clock fail
Cursor Keys to move, CTRL-U to save, ESC to abandon
=================================================================================
Use<SPACEBAR>/<+>/<-> to select

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The conditions which cause the alarm to operate may be selected from the System
Alarms menu page (shown below). Each of the possible Alarm conditions may be set to any
of the following actions:
a) NO ACTION The events will not cause the relay contacts to operate, or the
event to be logged.
b) LOG ONLY The events will not cause the relay contacts to operate, but the
event will be logged.
c) MINOR The event will be logged, and will cause the MINOR alarm
LED to illuminate, and the MINOR alarm relay contacts to operate.
d) MAJOR The event will be logged, and will cause the MAJOR alarm
LED to illuminate, and the MAJOR alarm relay contacts to operate.
Note that the screen display also indicates the highest active alarm status (None, Minor or
MAJOR), to the right of the 'Alarm' page prompt on the top right of the screen.
The reasons for which an alarm may be reported as 'FAULT' are identified below:
Link Carrier Loss
The local Multiplexer cannot identify a valid synchronisation sequence (FAS, CRC4
etc) from the remote multiplexer.
2 MEGABITE1 MULTIPLEXER V1.01
=============================== 11:47 06/01/97 ==================================
Main Link (EUR) : SYNCHRONISED
Mode : NORMAL Nx64 Channels : 4
Framing : CRC4 D&I Channels : 1
Idle Bandwidth : 0K * System Alarms : Minor
Clock Reference : INTERNAL Statistics : Main Link
Configuration : >LOCAL Events : Log
Event Action Status
Link Carrier Loss : MAJOR OK
Timeslot Mismatch : MAJOR OK
D&I Carrier Loss : MINOR FAULT
D&I Remote Alarm : MINOR OK
Nx64 Control Off : NO ACTION OK
Nx64 Clock Fail : LOG ONLY OK
Remote Alarm : MAJOR OK
Link BER High : MINOR OK BER Threshold : 1E-8
Cursor Keys to move, CTRL-U to save, ESC to abandon
=================================================================================
Use<SPACEBAR>/<+>/<-> to select

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Timeslot Mismatch
The configuration in the local unit does not match that in the remote unit. This
would almost certainly lead to data errors on some channels.
D&I Carrier Loss
The Multiplexer cannot identify a valid synchronisation sequence (FAS, CRC4 etc)
from the unit attached to the D&I port.
D&I Remote Alarm
The unit attached to the D&I port is generating an alarm in the framing information,
that is, it is reporting that it has a problem.
Nx64 Control Off
One of the channel ports (which is in use) is not providing the multiplexer with a true
CONTROL signal. This may mean that the signals have not been connected at all.
Note that un-connected CONTROL inputs will produce a random ON or OFF
indication. Control inputs from ports which are not allocated in the timeslot map are
ignored.
Nx64 Clock Fail
One of the data channel cannot synchronise its clock to the global network clock.
This may occur if a channel is set to external clock, and either no clock at all is
connected, or the clock which is connected is the wrong rate.
Remote Alarm
Shows FAULT if a remote Alarm is being received from the remote multiplexer.
Remote alarms are generated by any condition set at the remote site to give a MAJOR
alarm. If you want a particular alarm to be reported through the remote alarm bit, you
must set its Action field to either MAJOR or MINOR.N Any alarm which is set to
MAJOR or MINOR will cause a remote alarm to be sent through the link.