MEGAPLEX-2000/MEGAPLEX-2100 I/O MODULE … · MEGAPLEX-2000/MEGAPLEX-2100 I/O MODULE FOUR-CHANNEL...

MEGAPLEX-2000/MEGAPLEX-2100 I/O MODULE

FOUR-CHANNEL HIGH-SPEED DATA MODULE, HS-Q/M

INSTALLATION AND OPERATION MANUAL

NOTICE

This manual contains information that is proprietary to RAD Data Communications. No part of thispublication may be reproduced in any form whatsoever without prior written approval by RAD DataCommunications.

No representation or warranties for fitness for any purpose other than what is specifically mentioned in thismanual is made either by RAD Data Communications or its agents.

RAD Data Communications reserves the right to revise this publication and make changes without obligationto notify any person of such revisions or changes.

For further information contact RAD Data Communications at the address below or contact your localdistributor.

RAD data communications RAD data communications RAD data communications Headquarters U.S. EAST U.S. WEST12 Hanechoshet Street 900 Corporate Drive 7711 Center Avenue #350Tel Aviv 69710, Israel Mahwah, NJ 07430 USA Huntington Beach, CA 92647 USATel: 972-3-6458181 Tel: (201) 529-1100 Tel: (714) 897-2448Fax: 972-3-6498250 Fax: (201) 529-5777 Fax: (714)891-1764E-mail: [email protected] E-mail: [email protected]

© 1997 RAD Data Communications Ltd. Pub. No.264-209-12/97

TABLE OF CONTENTS

Page

Chapter 1. INTRODUCTION

1-1. FUNCTIONAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

1-2. TECHNICAL SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

Chapter 2. MODULE INSTALLATION AND OPERATION

2-1. GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

2-2. INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Module Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1Internal Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1Module Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

2-3. CONFIGURATION INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . 2-3

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3Module Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3Channel Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3Time Slot Assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4

Chapter 3. ALARMS & DIAGNOSTICS

3-1. GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3-2. ALARM MESSAGES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3-3. DIAGNOSTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Loopback Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3Local Digital Loopback (Local Loop) . . . . . . . . . . . . . . . . . . . . . . . 3-3Remote Digital Loopback (Remote Loop) . . . . . . . . . . . . . . . . . . . . 3-4External Modem Loopback (External Modem Remote Loop) . . . . . . . . . . 3-5Externally Initiated Local Modem Loopback . . . . . . . . . . . . . . . . . . . 3-6

Bit Error Rate Testing (BERT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7Patching (MEGAPLEX-2000/MEGAPLEX-2004 only) . . . . . . . . . . . . . . . 3-7Monitoring (MEGAPLEX-2000/MEGAPLEX-2004 only) . . . . . . . . . . . . . 3-7Recommended Test Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8

Appendix A. CONNECTION DATA

A-1. DATA CHANNEL INTERFACE SIGNALS . . . . . . . . . . . . . . . . . . . . . A-1

HS-Q/M Installation and Operation Manual i

LIST OF ILLUSTRATIONS

Page

Figure 1-1. Typical HS-Q/M Application . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Figure 2-1. Module HS-Q/M Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

Figure 3-1. Local Loopback, Signal Path . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

Figure 3-2. Remote Loopback, Signal Path . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

Figure 3-3. External Modem Loopback, Signal Path . . . . . . . . . . . . . . . . . . . . . 3-5

Figure 3-4. Externally Initiated Local Modem Loopback, Signal Path with Local V.54 Loop 2 Support Enabled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

Figure 3-5. Externally Initiated Local Modem Loopback, Signal Path with Local V.54 Loop 2 Support Disabled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

LIST OF TABLES

Page

Table 2-1. Module HS-Q/M, Panel Components . . . . . . . . . . . . . . . . . . . . . . . 2-2

Table 2-2. Channel Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Table 3-1. HS-Q/M Alarm Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Table A-1. Data Channel Interface Signals . . . . . . . . . . . . . . . . . . . . . . . . . . A-1

ii HS-Q/M Installation and Operation Manual

Chapter 1.

INTRODUCTION

1-1. FUNCTIONAL DESCRIPTION

The HS-Q/M module is a four-channel high-speed data sub-multiplexer for the Modular T1/E1 Multiplexer SystemsMEGAPLEX-2100, MEGAPLEX-2104, MEGAPLEX-2000, and MEGAPLEX-2004, that provides an integratedsystems solution for tail-end applications that require providing full-duplex access to the multiplexed data link forremotely located data equipment such as computer terminals, statistical multiplexers, etc.

NOTE

In this manual, the generic term MEGAPLEX is used when the information isapplicable to all the multiplexer versions listed above. The complete designation isused only for information applicable to a specific version.

The HS-Q/M module provides four high-speed synchronous data channels with built-in short-range modemsthat are fully compatible with the SRM-8H miniature high-speed short-range modem offered by RAD. EachHS-Q/M channel supports data rates of 32, 56 and 64 kbps. Each HS-Q/M high-speed data channel terminatesin an RJ-45 eight-pin connector. The built-in modems of the HS-Q/M module are intended for operation overunconditioned 4-wire telephone loops (two twisted pairs). Typical ranges are up to 10 km (6 miles) overAWG 19 (0.9 mm) pairs, up to 4.5 km (2.8 miles) over AWG 24 (0.5 mm) pairs, and up to 3.2 km (2 miles)over AWG 26 (0.4 mm) pairs.

Each of the HS-Q/M channels provides the receive timing signal to the built-in short-range modem, and accepts atransmit clock from the modem. Therefore, the HS-Q/M channel determines the timing of the data sent to theexternal modem. To ensure that the same timing is used on the transmit direction (from the external modem to theHS-Q/M channel), the external modem must operate with loopback timing. The transmit clock is recovered by thebuilt-in modem from the line signal received from the external SRM-8H modem. As an additional option, therecovered clock of channel 1 of an HS-Q/M module can be selected as an external reference for the MEGAPLEXnodal clock. All the module operating parameters are controlled by MEGAPLEX system management. Thetime slots assigned to each HS-Q/M channel in the T1 or E1 main link frame can be individually assigned bythe user (the MEGAPLEX-2000/MEGAPLEX-2004 system also supports automatic assignment). Channelsoperating at 32 kbps require full time slot.

User-controlled manual assignment allows the routing of the bit stream generated by each local channel to anychannel of an HS-Q/M, HS-Q, HS-2, HS-3, HS-4, TRE, HS-703, LS-6, MBE, VC-2, and other compatiblemodules installed in the remote MEGAPLEX unit.

HS-Q/M Installation and Operation Manual 1-1

Self-diagnostics upon power-up, as well as powerful testing capabilities controlled by means of the systemmanagement, reduce downtime to a minimum. The test and loopback functions, that can be individuallyactivated by the system management for each module channel, include:

•• Local digital loopback.•• Remote digital loopback.•• Bit error rate testing (BERT) on the desired module channel.•• For MEGAPLEX-2000/MEGAPLEX-2004 only: routing (patching) of the data stream carried by the

desired local or remote channel to the TEST port of the local CL module, and monitoring of the datareceived by the desired local or remote channel by means of test equipment connected to the TEST port.

•• External modem loopback similar to ITU-T Rec. V.54 loop 2, activated on the external modem.•• Local loopback similar to ITU-T Rec. V.54 loop activated on the internal channel modem upon

request of the external modem. This function can be disabled by the user: in this case, the remoteloopback activation command is transparently transferred through the HS-Q/M channel. Therefore,when this type of loopback is disabled, the modem sending the command can activate the loopbackon the external modem at the remote end of the link.

In addition to the loopbacks listed above, the rear panel of the HS-Q/M module includes two status indicatorsfor each channel:

•• CD (carrier detect) indicator, lights when a valid signal is received from the external modem connectedto the corresponding module channel.

•• TST (test) indicator, lights when a loopback is activated on the corresponding channel (this includesloopbacks activated on the internal modem, and external modem (V.54 loop 2) loopbacks).

Figure 1-1 shows a typical HS-Q/M application.

Figure 1-1. Typical HS-Q/M Application

CHAPTER 1 - INTRODUCTION

1-2 HS-Q/M Installation and Operation Manual

1-2. TECHNICAL SPECIFICATIONS

Number of channels Four

Channel data rate Synchronous 32, 56 and 64 kbps data transmission, withSRM-8H-compatible built-in modem

Line type 4-wire unconditioned telephone loops

Transmit level 0 dBm

Typical range – 10 km (6 miles) over AWG-19 (0.9 mm) pairs– 4.5 km (2.8 miles) over AWG-24 (0.5 mm) pairs– 3.2 km (2 miles) over AWG-26 (0.4 mm) pairs

Connectors One RJ-45 eight-pin connector per channel

Diagnostics (per channel)Test functions and loopbacks – Local digital loopback

– Remote digital loopback– Patching (interruptive monitor) - on MEGAPLEX-2000 and

MEGAPLEX-2004 only– Monitoring (uninterruptive monitor) - on MEGAPLEX-2000

and MEGAPLEX-2004 only– Internal BERT– Remote (external) modem loopback command (similar to

ITU-T Rec. V.54 loop 2)– Local loopback upon command from external modem (this

type of loopback can be disabled by the user)

Indicators – CD (green): lights when a valid signal is received from theremote modem

– TST (red): lights when a modem loopback is active

Configuration Programmable by the MEGAPLEX system management functions

TECHNICAL SPECIFICATIONS


NOTES


Chapter 2.

MODULE INSTALLATIONAND OPERATION

2-1. GENERAL

This chapter provides installation, configuration and operation instructions for the HS-Q/M module. Theinformation presented in this chapter supplements the general MEGAPLEX-2000/MEGAPLEX-2100installation, configuration and operation instructions contained in Part I of the corresponding system Installationand Operation Manual.

CAUTION

The HS-Q/M module contains components sensitive to electrostaticdischarge (ESD). To prevent ESD damage, always hold the module by itssides, and do not touch the module components or connectors.

2-2. INSTALLATION

Module PanelThe panel of the HS-Q/M module is shown in figure 2-1. The rear panel includes two indicators and oneconnector for each module channel. Table 2-1 explains the functions of these components.

Internal SettingsThe HS-Q/M module has no internal settings. All the module functions are programmable by means of systemmanagement.


Table 2-1. Module HS-Q/M, Panel Components

Item Description

TST Indicator Lights when the internal modem of the corresponding channel of the HS-Q/Mmodule is engaged in a test

CD Indicator Lights when the corresponding channel of the HS-Q/M module receives a validcarrier signal from the external modem

CH Connector RJ-11 six-pin connector for connection to the corresponding channel. Connector pin assignments and functions are given in Appendix A

Figure 2-1. Module HS-Q/M Panel

Module InstallationRefer to the system installation plan and insert the HS-Q/M module into the assigned I/O slot of theMEGAPLEX enclosure. The module starts operating as soon as it is plugged into an operating enclosure.

Identify the cables intended for connection to this module, and connect the cables to the corresponding moduleconnectors.

CAUTION

The HS-Q/M module does not include gas arrestors on the line terminals. Therequired protection must be externally provided by the user, in accordance with thespecific requirements of the particular application.

CHAPTER 2 – MODULE INSTALLATION & OPERATION


2-3. CONFIGURATION INSTRUCTIONS

GeneralThis section provides information on the configuration parameters of the HS-Q/M modules. The configurationactivities required to select the desired values of these parameters are performed by means of the managementsystem used to control the MEGAPLEX unit. The instructions appearing in this section assume you arefamiliar with the management system being used:

•• For MEGAPLEX-2000 systems: System Manager (covered by Chapter 4 in Part I of theMEGAPLEX-2000 or MEGAPLEX-2004 Installation and Operation Manual), or a supervisionterminal (covered by Appendix C in Part I).

•• For the MEGAPLEX-2100 systems: supervision terminal (covered by Chapter 3 of theMEGAPLEX-2100 Installation and Operation Manual), or a network management system, e.g., theRADview network management system (refer to the RADview User’s Manual for instructions).

Two types of parameters are available:

•• Module parameters.•• Channel parameters.

Module Parameters

The HS-Q/M modules have only one parameter, the main link to which the module channels will be connected:

•• For MEGAPLEX-2100 systems, the main link is specified by indicating the number of the I/O slot inwhich the desired main link module is installed.

•• For MEGAPLEX-2000 systems, the main link number is explicitly identified on the individual channelconfiguration screens. Changing the link on one screen automatically updates the link for the othermodule channels.

Channel Parameters

Table 2-2 explains the programmable parameters of the HS-Q/M channels, and their range of values.

Table 2-2. Channel Parameters

Parameter Description

Connect Determines whether the channel is connected to the selected main link:YES Channel is connected, and carry trafficNO Channel is disconnected. You can still program the desired parameters, so the module will be ready to operate when needed.

Destination(MEGAPLEX-2000only)

Indicates the name of the remote MEGAPLEX-2000 unit, its I/O slot, the type ofremote module, and the channel that will communicate with this channel.This field is displayed only for a point-to-point configuration

Rate (kbps) Specifies the data rate of this channel. The available rates are 32, 56 and 64 kbps

Loop Enables/disables the activation of the V.54 loop 2 on the local modem:ENABLED The reception of a V.54 loop 2 command activates the loopback on the

external modemDISABLED The local internal modem ignores the command and transfers it

transparently

CONFIGURATION INSTRUCTIONS


Parameter Description

FIFO Size Selects the size of the FIFO buffer used by the channel.

Always displays AUTO, meaning "automatic FIFO size selection". The AUTO valueis ±16 bits

Priority Level(MEGAPLEX-2000only)

Selects the priority level of the channels. This field is displayed only when theAggregate Mode is set to one of the Priority Bumping modes. The priority bumpingfunction is explained in Chapter 1 of Part I of the MEGAPLEX-2000 Installation andOperation Manual.

LOW the module channels have low priorityHIGH the module channels have high priority

Link to(MEGAPLEX-2000only)

Selects the main link that will carry the data stream generated by this HS-Q/Mmodule, when the Aggregate Mode is Dual Link, or one of the Priority Bumpingmodes.

The dual link feature is explained in Chapter 1 of Part I of the MEGAPLEX-2000Installation and Operation Manual.

LINK A the module data stream is routed to main link ALINK B the module data stream is routed to main link B

NOTE Although the link can be selected on each channel configurationscreen, the selection made on any screen automatically changes

all of the four selections.

TDM Link (only forMEGAPLEX-2100)

Selects the main link to which the module will be connected. The main link isspecified by indicating the number of the I/O slot in which the desired main linkmodule is installed

Time Slot Assignment

After performing the configuration of the individual module channels, it is necessary to assign main link timeslots to each connected channel.

•• For the MEGAPLEX-2000, you may perform manual time slot assignment in accordance with the generalinstructions provided in Part I, Chapter 4 (CONFIGURATION – Mux Edit – TS Assignment) of theMEGAPLEX-2000 Installation and Operation Manual. After performing the previous configuration steps,the selection list already includes the active channels of the HS-Q/M module and shows one time slot for eachactive channel.

The MEGAPLEX-2000 also supports automatic time slot assignment.

•• For the MEGAPLEX-2100, you must always perform manual time slot assignment, as explained inChapter 3 of the MEGAPLEX-2100 Installation and Operation Manual.

Table 2-2. Channel Parameters (Cont’d)

CHAPTER 2 – MODULE INSTALLATION & OPERATION


Chapter 3.

ALARMS & DIAGNOSTICS

3-1. GENERAL

This chapter provides information on the alarms generated by the HS-Q/M module, specifies their type (eventor state), and provides instructions for using the module-specific diagnostic functions.

The diagnostic information presented in this chapter supplements the general MEGAPLEX-2000 andMEGAPLEX-2100 diagnostics operation instructions contained in Part I of the corresponding system manual.

3-2. ALARM MESSAGES

Table 3-1 lists the specific alarm messages generated by the HS-Q/M module, specifies their type, and explainstheir interpretation. The module generates additional alarm messages, which are not specific to HS-Q/M modules;these messages are explained in Appendix B in Part I of the corresponding system manual.

Note that each message has an identification code. The alarm codes used by MEGAPLEX-2100 (listed underthe heading 2100) differ from those of the MEGAPLEX-2000 (listed under the heading 2000), however thealarm types are similar.

Table 3-1. HS-Q/M Alarm Messages

CodeMessage Type Interpretation

2000 2100

1 021 MODULE WAS REMOVED Event The module has been taken out of its slot.

2 022 MODULE WAS INSERTED Event The module has been inserted.

3 023 MODULE RESET OCCURRED Event The module has been automatically reset.

4 024 MODULE INITERROR/HARDWARE FAILURE

State Module initialization has failed, or a hardwaremalfunction has been detected in this module.

5 025 NOT PROGRAMMED MODULE State(Minor)

The module that has been read from theMEGAPLEX unit is not programmed in theactive data base.

026 PROGRAMMED/INSTALL MODULE MISMATCH

State The module that has been read from theMEGAPLEX unit does not match the moduleprogrammed in the active data base


CodeMessage Type Interpretation

2000 2100

6 031 COMMUNICATION FAILURE (MP) Event The CL module reported a temporary failure inthe communication with this HS-Q/M module

8 029 NOT SUPPORTED SOFTWAREVER

State The HS-Q/M module includes an old softwareversion that differs from the version expectedby the CL module

94959697

240 LOSS OF SIGNAL IN CH1LOSS OF SIGNAL IN CH2LOSS OF SIGNAL IN CH3LOSS OF SIGNAL IN CH4

State The internal modem of the specified channeldoes not receive any signal from the externalmodem

75

76

77

78

241 BUFFER OVERFLOW/UNDERFLOWIN CH1BUFFER OVERFLOW/UNDERFLOWIN CH2BUFFER OVERFLOW/UNDERFLOWIN CH3BUFFER OVERFLOW/UNDERFLOWIN CH4

Event A FIFO overflown/underflown event hasoccurred. If the event recurs, it is usuallycaused by incorrect selection of the timingmode on the module channels and/or user’sequipment, or by technical problems(unstable clock) in the timing circuits of theuser’s equipment

3-3. DIAGNOSTICS

The available test and diagnostics functions are:

•• Connection of a local digital loopback on the desired module channel.

•• Remote digital loopback on the desired module channel.

•• Bit error rate testing (BERT) on the desired module channel.

•• Only for modules operating in the MEGAPLEX-2000/MEGAPLEX-2004:

° Routing (patching) of the data streams carried by the desired local or remote channel to the TESTport of the local CL module (interruptive).

° Monitoring of the data received by the desired local or remote channel by means of test equipmentconnected to the TEST port (non-interruptive).

•• External modem loopback command, similar to ITU-T Rec. V.54 loop 2, activated on the externalmodem.

•• Local loopback on the internal channel modem, activated only upon request of the remote external modem.

For modules operating in a MEGAPLEX-2100 system, when a test or loopback is activated, the user can alsospecify the time it remains active: the range is 1 through 30 minutes, in 1-minute steps. After the specified time,the test or loopback is automatically deactivated, thereby reducing the management workload during systemtroubleshooting. The default selection is continuous connection, that is, the test or loopback remains activeuntil canceled by a user’s command.

The following sections describe the available test activities.

Table 3-1. HS-Q/M Alarm Messages (Cont’d)

CHAPTER 3 – ALARMS AND DIAGNOSTICS


Loopback Types

Local Digital Loopback (Local Loop)

The local digital loopback is performed at the input of the channel digital transmit path, by returning thetransmit signal provided by the internal modem of the channel to the input of the internal modem transmit path.The digital transmit signal is still sent to the remote MEGAPLEX unit.

The loopback signal path is shown in figure 3-1.

Figure 3-1. Local Loopback, Signal Path

DIAGNOSTICS


Remote Digital Loopback (Remote Loop)

The remote loopback is performed at the output of the channel digital transmit path, by returning the digitaloutput signal to the input of the channel digital receive path.


Figure 3-2. Remote Loopback, Signal Path



External Modem Loopback (External Modem Remote Loop)

The remote modem loopback is a ITU-T Rec. V.54 loop 2 performed by the external modem connected to theHS-Q/M channel, in response to the command sent via the internal channel modem. When the loopback isactivated, the external modem returns the receive signal via the transmit path.


Figure 3-3. External Modem Loopback, Signal Path

DIAGNOSTICS


Externally Initiated Local Modem Loopback

The externally initiated local modem loopback is a ITU-T Rec. V.54 loop 2 performed by the internal channelmodem, in response to the command sent by the external modem connected to the local HS-Q/M channel (thisloop cannot be connected by a system management command).

When the loopback is activated, the internal modem returns the digital receive signal toward the externalmodem via the transmit path. The transmit signal provided by the receive path of the internal modem is stillsent to the remote MEGAPLEX unit.

Note that when the external modem, e.g., an SRM-8H, sends the loopback command, it switches to its internalclock. This may cause system timing problems: for example, if the loopback is activated on channel 1 of theHS-Q/M module, and this channel serves as the MEGAPLEX system timing source, this operation replaces thecurrent system timing reference with the internal oscillator of the modem, whose accuracy requirements areusually quite relaxed.

The loopback signal path, for the case the local module channel is configured to enable the activation of thisloopback, is shown in figure 3-4.

Figure 3-4. Externally Initiated Local Modem Loopback, Signal Path with Local V.54 Loop 2 SupportEnabled

The user can disable the activation of this loopback (note that this also disables the possibility to activate theV.54 loop 2 on the external modem from the MEGAPLEX system). When the loopbacks are disabled on theboth MEGAPLEX units connected in a link, the loopback command sent by the external modem will betransparently transfered through the MEGALEX link, and will be received by the remote modem. As a result,the V.54 loop 2 will be activated on the remote modem, as shown in figure 3-5. The modem which initiatedthe V.54 loop changes its clock to internal, and as a result, the remote modem automatically changes its clockto receive. Note, however, that if the MEGAPLEX system timing source is not locked to the timing of theHS-Q/M channel being tested, bit errors may occur during the test due to clock slips.

HS-Q/M

I/O M

OD

UL

ES

HS-Q

I/O M

OD

UL

ES

Local Unit Remote Unit

User orTest

Equipment

.

.

.

.

.

.

.

.MODEM

ModemUser or

TestEquipment



Figure 3-5. Externally Initiated Local Modem Loopback, Signal Path with Local V.54 Loop 2 SupportDisabled

Bit Error Rate Testing (BERT)The BERT is used to check for proper data transmission through a selected channel, and obtain a qualitativeevaluation of data transmission without using external test equipment.

The bit error rate is measured by applying a 24-1 bit pseudo-random test sequence generated by an on-boardgenerator to the input of the channel transmit path. The transmitted data is returned by means of a loopbacksomewhere along the data path (e.g., by connecting a local or remote main link loopback) to the receive pathof the module channel, and routed to a test sequence evaluator. Instead of using a loopback, it is also possibleto activate the BERT at both ends of the link, because the same data patterns are used at both ends. Theevaluator compares the received data, bit by bit, to the original data and detects any difference (bit error). Theoutput of the test sequence evaluator is sampled during module polling, to check whether errors were detectedin the interval between consecutive pollings. The total number of intervals during which errors were detectedare counted and can be displayed to the operator.

During the BERT test, the channel is disconnected from the user data equipment.

Only one BERT test can be activated at any time on each HS-Q/M module.

Patching (MEGAPLEX-2000/MEGAPLEX-2004 only)The patch function is used to connect test equipment to a selected channel, e.g., for performing bit error ratemeasurements, etc...

The patching is performed by disconnecting the user data equipment from the selected channel, and routing thechannel to the TEST port of the CL module. Either the local channel, or the remote channel can be routed, inaccordance with the patch type.

HS-Q/M

I/O M

OD

UL

ES

HS-Q

I/O M

OD

UL

ES

Local Unit Remote Unit

.

.

.

.

.

.

.

.

ModemUser or

TestEquipment

.

.

.

.

.

.

.

.

ModemUser or

TestEquipment

DIAGNOSTICS


Only one patch or monitoring connection can be activated at any time on the MEGAPLEX-2000 orMEGAPLEX-2004 unit. The interface of the TEST port is selected by connecting the appropriate type of cableto the TEST connector. If two CL modules are installed in the MEGAPLEX-2000/MEGAPLEX-2004, theirTEST ports are effectively connected in parallel, therefore the connection (only one!) can be made to eithermodule.

Refer to Chapter 5 of Part I in the MEGAPLEX-2000/MEGAPLEX-2004 Installation and Operation Manualfor detailed information.

Monitoring (MEGAPLEX-2000/MEGAPLEX-2004 only)The monitoring function is used to monitor the data received or transmitted by a selected channel. Themonitoring is performed by routing the transmit or receive data, respectively, of the local or remote channelto the TEST port of the CL module, in parallel with the data sent to the user data equipment.

Refer to Chapter 5 of Part I in the MEGAPLEX-2000/MEGAPLEX-2004 Installation and Operation Manualfor detailed information.

Recommended Test SequenceThe loops available on the HS-Q/M module provide a rapid and efficient way to identify the general locationof a fault at either of the HS-Q/M modules connected in a link, at the external modem or external equipment,or in the connections to the channels.

If a complaint is received regarding the transmission of data through one of the HS-Q/M channels, perform thefollowing procedure until the problem is located. After each step, continue to the next step only if the specifiedtest is successfully completed.

NOTE

If the problem is detected when a connection between two new users is activated forthe first time, before starting the troubleshooting procedure described below youshould thoroughly check the time slot allocation and the configuration at the twoMEGAPLEX units that provide the new connection.

•• Request the user to perform a local loopback test on the external modem connected to its equipment. Ifthe user equipment does not receive its own signal, the problem is in the connections between the userequipment and the external modem to which it is connected. After correcting the problem, continuetroubleshooting as explained below.

•• Send a remote loop command from the external modem to activate the externally-initiated local modemloopback on the HS-Q/M channel. The user equipment connected to the external modem must receiveits own signal.

If the signal is not received, the problem is probably in the connections between the external modem andthe HS-Q/M channel, or in the external modem. If after checking these items the problem in the local mo-dem loopback persists, replace the local HS-Q/M module.

•• Activate the local digital loopback on the HS-Q/M channel. The user equipment connected to theexternal modem must receive its own signal. If the signal is not received, replace the local HS-Q/Mmodule.



•• Activate the remote digital loopback on the remote module channel connected to the local HS-Q/Mchannel (this is not necessarily another HS-Q/M module). The user equipment connected to the localexternal modem must receive its own signal.

If the signal is received, the problem is in the equipment located at the remote location, or in the connec-tions of the remote user equipment.

•• If the signal is not received when the remote digital loopback is activated, activate the local main linkloop on the local MEGAPLEX unit.

If the user equipment connected to the local external modem does not receive its own signal when themain link loop is connected, the problem is in the local MEGAPLEX unit.

•• If the signal is received when the main link local loopback is activated, activate the remote main linkloop.

If the user equipment connected to the local external modem does not receive its own signal, the problemis either in the time slot allocation, or in the remote MEGAPLEX unit.

DIAGNOSTICS


Appendix A.

CONNECTION DATA

A-1. DATA CHANNEL INTERFACE SIGNALS

Each channel of the HS-Q/M module has an RJ-45 connector wired in accordance with Table A-1.

Table A-1. Data Channel Interface Signals

Pin Function Direction

1 Frame Ground –

2 Ground –

3 Receive wire In

4 Transmit wire Out

5 Transmit wire Out

6 Receive wire In

7, 8 Not connected –

HS-Q/M Installation and Operation Manual A-1

MEGAPLEX-2000/MEGAPLEX-2100 I/O MODULE … · MEGAPLEX-2000/MEGAPLEX-2100 I/O MODULE FOUR-CHANNEL...

Documents

Transcript of MEGAPLEX-2000/MEGAPLEX-2100 I/O MODULE … · MEGAPLEX-2000/MEGAPLEX-2100 I/O MODULE FOUR-CHANNEL...