datacomm 610/612 network terminating unit - gdc · datacomm 610/612 network terminating unit...

Publication No. 072R114-000Issue 3, May 1997

OPERATING AND INSTALLATION INSTRUCTIONSFOR

DataComm 610/612 NETWORK TERMINATING

UNIT

General DataComm, Inc.MIDDLEBURY, CONNECTICUT06762-1299

ATTENTION!STATIC SENSITIVE DEVICES

PROPER HANDLING AND GROUNDINGPRECAUTIONS REQUIRED

This equipment contains electrostatic sensitive devices. Use ESD precautionary procedureswhen removing or inserting parts or printed circuit (pc) cards. Keep parts and pc cards intheir antistatic packaging material until ready to install.

The use of an antistatic wrist strap, connected to the grounded equipment frame or chassis, isrecommended when handling pc cards during installation, removal, or setting of on-boardoption switches. Do not use a conductive tool, such as a screwdriver or paper clip, to set theposition of the option switches.

INSTALLATION SAFETY INSTRUCTIONS

a. Never install telephone wiring during a lightning storm.

b. Never install telephone jacks in a wet location unless the jack is specifically designedfor wet locations.

c. Never touch uninsulated telephone wires or terminals unless the telephone line has beendisconnected at the network interface.

d. Use caution when installing or modifying telephone lines.

CAUTIONPotentially hazardous voltages exist within this unit.

DataComm 610/612NETWORK TERMINATING

UNIT

(GDC PART NOS. 048A080-XXX,and 048P080-001, -002)

General DataComm, Inc. (GDC)Middlebury, Connecticut 06762-1299

This product was designed and manufactured by

WARNING

This equipment has been tested and found to comply with the limits for a Class Adigital device , pursuant to Part 15 of the FCC rules. These limits are designed toprovide reasonable protection against harmful interference when the equipment isoperated in a commercial environment. This equipment generates, uses and canradiate radio frequency energy and, if not installed and used in accordance with theinstruction manual, may cause harmful interference to radio communications.Operation of this equipment in a residential area is likely to cause harmfulinterference, in which case the user will be required to correct the interference at hisown expense.

The user is cautioned that any changes or modifications not expressly approved by theparty responsible for compliance would void the user's authority to operate theequipment.

CRC-REQUIRED NOTIFICATION

This equipment is a Class A digital apparatus which complies with the RadioInterference Regulations, CRC c.1374.

PUBLICATION NOTICE

This manual has been carefully compiled and checked for accuracy. The infor-mation in this manual does not constitute a warranty of performance. Further-more, GDC reserves the right to revise this publication and make changes from time totime in the content thereof. GDC assumes no liability for losses incurred as a result ofout-of-date or incorrect information contained in this manual.

The features described herein may not exist on all versions of the software and aresubject to change without notice.

READER’S COMMENTS

Comments regarding this manual should be addressed to:

Publications DepartmentGeneral DataComm, Inc.1579 Straits TurnpikeP.O Box 1299Middlebury, CT 06762-1299

PROPRIETARY NOTICE

This publication contains information proprietary and confidential to GeneralDataComm, Inc. Any reproduction, disclosure, or use of this publication is expresslyprohibited except as General DataComm, Inc., may otherwise authorize in writing.

Copyright, General DataComm, Inc., 1994

WARNING

This equipment generates, uses, and can radiate radio frequency energy and if notinstalled and used in accordance with the instruction manual, may cause interferenceto radio communications. It has been tested and found to comply with the limits for aClass A computing device pursuant to Subpart J of Part 15 of FCC Rules, which aredesigned to provide reasonable protection against such interference when operated in acommercial environment. Operation of this equipment in a residential area is likely tocause interference, in which case the user at his own expense will be required to takewhatever measures may be required to correct the interference.

CAUTION

To Reduce the Risk of Electrical Shock, Do Not Remove the Cover.Refer Servicing to Qualified Service Personnel.

ACHTUNG

Um einen elektrischen Schlag zu vermeiden, nicht das Gehäuseöffnen! Änderungen und Reparaturen dürfen nur vonqualifizierten Personen ausgeführt werden.

CRC-REQUIRED NOTIFICATIONThis equipment is a Class A digital apparatus which complies with the RadioInterference Regulations, CRC c.1374.

PUBLICATION NOTICEThis manual has been carefully compiled and checked for accuracy. The informationin this manual does not constitute a warranty of performance. Furthermore, GDCreserves the right to revise this publication and make changes from time to time in thecontent thereof. GDC assumes no liability for losses incurred as a result of out-of-dateor incorrect information contained in this manual.

READERS' COMMENTS

Comments regarding this manual should be addressed to:

Publications DepartmentGeneral DataComm, Inc.1579 Straits TurnpikeP.O. Box 1299Middlebury, CT 06762-1299

PROPRIETARY NOTICEThis publication contains information proprietary and confidential to GeneralDataComm, Inc. Any reproduction, disclosure, or use of this publication is expresslyprohibited except as General DataComm, Inc., may otherwise authorize in writing.

Country code configurations/default group selectable data equip. U.S. Patent No. 4841561

Copyright, General DataComm, Inc., 1994

ANALOG DEVICES

NOTICE FOR USERS OF FCC-REGISTERED EQUIPMENT

Read before using this technical manual or installing subject equipment.

The following instructions are provided to ensure compliance with the Federal CommunicationsCommission (FCC) Rules, Part 68.

A. This equipment complies with Part 68 of the FCC Rules. On the underside of this equipment is a labelthat contains, along with other information, the FCC registration number and ringer equivalencenumber (REN) for this equipment. This information, if requested, must be provided to the telephonecompany.

B. The applicable registration jack USOCs for this equipment are as follows:

Operation JackProgrammablePermissive

C. For single and two-line equipment that connects to the telephone network via a plug and jack, the plugand jack must comply with the FCC Part 68 Rules. An FCC compliant telephone modular plug andtelephone cord is provided with this equipment. This equipment is designed to be connected to thetelephone network or premises wiring, using a compatible modular jack which is Part 68 compliant.See installation instructions for details.

D. The REN (Ringer Equivalence Number) is used to determine how many devices can be connected toyour telephone line. In most areas, the sum of the RENs of all devices on any one line should notexceed (5.0). To be certain of the number of devices that may be connected to a line, as determined bythe total RENs, contact the local phone company.

E. If the causes harm to the telephone network, the telephone company will notify youin advance that temporary discontinuance of service may be required. But if advance notice is notpractical, the telephone company will notify the customer as soon as possible. Also, you will be advisedof your right to file a complaint with the FCC if you believe it is necessary.

F. The telephone company may make changes in its facilities, equipment, operations or procedures thatcould affect the operation of the equipment. If this happens the telephone company will provide advancenotice in order for you to make necessary modifications to maintain uninterrupted service.

G. If trouble is experienced with the , contact General DataComm Service Corp., 6Rubber Ave, Naugatuck, CT 06770 phone (203) 729-0271 for repair and/or warranty information. If theequipment is causing harm to the telephone network, the telephone company may request that youdisconnect the equipment until the problem is resolved.

H. In the event the equipment needs repair it must be sent back to the company or listed authorized agent.Under FCC rules, no customer is authorized to repair this equipment. Any repair or modification willnull and void the FCC registration and the warranty of this equipment.

I. The cannot be used on Public Coin Phone Service or Party Lines. Connection toParty Line Service is subject to state tariffs. Contact the state public utility commission, public servicecommission or corporation commission for information.

Rev. 6, June 1993

CANADIAN DEPARTMENT OF COMMUNICATIONS (DOC) REQUIRED NOTIFICATION

FOR USERS OF DOC-CERTIFIED EQUIPMENT

Read before using this technical manual or installing subject equipment.

The Canadian Department of Communications label identifies certified equipment. This certificationmeans that the equipment meets certain telecommunications network protective, operational, and safetyrequirements. The Department does not guarantee the equipment will operate to the user's satisfaction.

Before installing this equipment, users should ensure that it is permissible to be connected to the facilities ofthe local telecommunications company. The equipment must also be installed using an acceptable method ofconnection. In some cases, the company's inside wiring associated with a single line individual servicemay be extended by means of a certified connector assembly (telephone extension cord). The customershould be aware that compliance with the above conditions may not prevent degradation of service in somesituations.

Repairs to certified equipment should be made by an authorized Canadian maintenance facility designatedby the supplier. Any repairs or alterations made by the user to this equipment, or equipment malfunctions,may give the telecommunications company cause to request the user to disconnect the equipment.

Users should ensure for their own protection that the electrical ground connections of the power utility,telephone lines, and internal metallic water pipe system, if present, are connected together. This precautionmay be particularly important in rural areas.

Caution: Users should not attempt to make such connections themselves, but should contact the appropriateelectric inspection authority, or electrician, as appropriate.

CANADIAN EMISSIONS REQUIREMENTS

“This digital apparatus does not exceed the (ClassA) limits for radio noise emissions from digitalapparatus set out in the Radio Interference Regulations of the Canadian Department ofCommunications.”

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Errata Sheetfor

Installation and Operation610/612 NTU

Publication 072R114-000, Issue 3

Overview

This publication reflects changes to the Installation and Operation for 610/612 NTU.

Preface - Replace or add Canadian Warning to read:

Industry Canada Notification

The Industry Canada label identifies certified equipment. This certification means thequipment meets telecommunications network protective, operation and safety requireas prescribed in the appropriate Terminal Equipment Technical Requirements documThe Department does not guarantee the equipment will operate to the user's satisfactBefore installing this equipment, users should ensure that it is permissible to be connethe facilities of the local telecommunications company. The equipment must also be insusing an acceptable method of connection. The customer should be aware that comwith the above conditions may not prevent degradation of service in some situations.Repairs to certified equipment should be coordinated by a representative designatedsupplier. Any repairs or alterations made by the user to this equipment, or equipmenfunctions, may give the telecommunications company cause to request the user to discthe equipment.Users should ensure for their own protection that the electrical ground connections power utility, telephone lines and internal metallic water pipe system, if present, are coed together. This precaution may be particularly important in rural areas.Caution: Users should not attempt to make such connections themselves, but should the appropriate electric inspection authority, or electrician, as appropriate.Notice: The Ringer Equivalence Number (REN) assigned to each terminal device proan indication of the maximum number of terminals allowed to be connected to a teleinterface. The termination on an interface may consist of any combination of devices sonly to the requirement that the sum of the Ringer Equivalence Numbers of all the ddoes not exceed 5.

Electromagnetic Compatibility

This Class A digital apparatus complies with Canadian ICES-003.

Avis D’industrie Canada

L’étiquette d’Industrie Canada identifie le matériel homologué. Cette étiquette certifie qmatériel est conforme aux normes de protection, d’exploitation et de sécurité des résetélécommunications, comme le prescrivent les documents concernant les exigenceniques relatives au matériel terminal. Le Ministère n’assure toutefois pas que le matérietionnera à la satisfaction de l’utilisateur.Avant d’installer ce matériel, l’utilisateur doit s’assurer qu’il est permis de le raccordeinstallations de l’entreprise locale de télécommunication. Le matériel doit également êstallé en suivant une méthode acceptée de raccordement. L’abonné ne doit pas oubl

General DataComm GDC Publication No. 072R114-E1

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est possible que la comformité aux conditions énoncées ci-dessus n’empêche pas la dtion du service dans certaines situations.Les réparations de matériel homologué doivent être coordonnées par un représentant par le fournisseur. L’entreprise de télécommunications peut demander à l’utilisatedébrancher un appareil à la suite de réparations ou de modifications effectuées par l’utiou à cause de mauvais fonctionnement.Pour sa propre protection, l’utilisateur doit s’assurer que tous les fils de mise à la terresource d’énergie électrique, des lignes téléphoniques et des canalisations d’eau métalliqy en a, sont raccordés ensemble. Cette précaution est particulièrement importante dangions rurales.Avertissement: L’utilisateur ne doit pas tenter de faire ces raccordements lui-même; ilavoir recours à un service d’inspection des installations électriques, ou à un électricienle cas.Avis: L’indice d’équivalence de la sonnerie (IES) assigné à chaque dispositif terminal inle nombre maximal de terminaux qui peuvent être raccordés à une interface. La termid’une interface téléphonique peut consister en une combinaison de quelques dispositseule condition que la somme d’indices d’équivalence de la sonnerie de tous les disn’excède pas 5.

La Compatibilité d’ Eléctro-magnetique

Cet appareil numerique de la classe A est conforme a la norme NMB-003 du Canada.

Service Support and TrainingVITAL Network Services, a General DataComm company, is committed to providing theservice support and training needed to install, manage, and maintain your GDC equipmGDC’s VITAL Network Services provides hands-on training courses through VITAL Net-work Services Global Technology Training Services. Courses range from basic data communications, modems and multiplexers, to complex network and ATM systems. Trainingcourses are available at our centers in the US, UK, France, Singapore and Mexico, as wat a customer’s site.For more information regarding GDC's VITAL Network Services’ service programs, traincourses, or for assistance with your support requirements, contact GDC's VITAL NetwoServices at the address or phone number listed below, or visit our website at: http//www.vital-netsvc.com

VITAL Network Services World Headquarters6 Rubber AvenueNaugatuck, Connecticut 06770 USA

North America:1 800 243 10301 888 248 48251 203 729 2461Training Information:1 203 729 0271French Speaking Canada:1 800 361 2552North America Fax:1 203 723 50121 203 729 7611

July 1998.

VITAL Network Services Regional Sales and Service Offices:

Europe, Middle East, AfricaVITAL Network ServicesMolly Millars CloseMolly Millars LaneWokingham, Berkshire RG41 2QF UK

Telephone: +44 1189 657200Training: +44 1189 657240Fax: +44 1189 657279

Central America, Latin AmericaVITAL Network ServicesPeriferico Sur 4225, Desp. 306C.P. 14210, Mexico D.F., Mexico

Telephone: +52 5 645 2238Training: +52 5 645 2238Fax: +52 5 645 5976

Asia PacificVITAL Network Services501 Orchard Road 05-05Wheelock Place, Singapore 238880

Telephone: +65 735 2123Training: +65 735 2123Fax: +65 735 6889

International Calling Code (+)When calling from outside the country of origin, use the appropriate International CallingCode where the + symbol is shown.

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Publications DepartmentTechnology CenterGeneral DataComm Industries, Inc.Middlebury, Ct 06762-1299

TABLE OF CONTENTS

Section &Subject Page

1 — INTRODUCTION

INTENDED USERS.....................................................................................................................................1-1

FEATURES..................................................................................................................................................1-1

PRODUCT DESCRIPTION .........................................................................................................................1-1

APPLICATIONS.......................................................................................................................................... 1-2

DIAGNOSTICS ............................................................................................................................................1-3

SERVICE AND TRAINING ........................................................................................................................1-3

2 — INSTALLATION

UNPACKING AND HANDLING.................................................................................................................2-1

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

Standalone Installation............................................................................................................................. 2-1

Rackmount Installation ...........................................................................................................................2-2

OPTION SELECTION................................................................................................................................. 2-2

ELECTRICAL CONNECTIONS..................................................................................................................2-8

Power - Standalone Enclosure................................................................................................................... 2-8

Power - Rackmount shelf .......................................................................................................................... 2-8

Business Equipment Connections............................................................................................................. 2-8

530 or X.21 Interface Card Connections.....................................................................................................2-8

Line Connections....................................................................................................................................... 2-9

Preoperational Check ................................................................................................................................2-13

3 — OPERATION

OVERVIEW................................................................................................................................................. 3-1

CONTROLS INDICATORS AND CONNECTORS.....................................................................................3-1

RACKMOUNT SHELF................................................................................................................................3-1

i

TABLE OF CONTENTS (Cont.)

Section &Subject Page

4 — TESTS

OVERVIEW................................................................................................................................................. 4-1

POINT-TO-POINT TESTING.....................................................................................................................4-2

LINE LOOPBACK TEST............................................................................................................................. 4-3

DIGITAL LOOPBACK TEST .....................................................................................................................4-5

REMOTE LOOPBACK ...............................................................................................................................4-7

END-TO-END SELF TEST .........................................................................................................................4-10

NETWORK LOOPBACK TESTS (EOC CONTROLLED) ..........................................................................4-12

TECHNICAL ASSISTANCE PROCEDURE................................................................................................ 4-14

TRAINING ..................................................................................................................................................4-15

APPENDIX A — TECHNICAL CHARACTERISTICS

APPENDIX B — BUSINESS EQUIPMENT (DTE) INTERFACE SIGNALS (ITU-T V.24/V.28)

APPENDIX C — BUSINESS EQUIPMENT (DTE) INTERFACE SIGNALS (ITU-T V.35)

APPENDIX D — BUSINESS EQUIPMENT (DTE) INTERFACE SIGNALS (530)

APPENDIX E — BUSINESS EQUIPMENT (DTE) INTERFACE SIGNALS (X.21)

APPENDIX F — GLOSSARY

INDEX

ii

LIST OF ILLUSTRATIONS

Section &Figure Page

1 —INTRODUCTION

1-1 POINT-TO-POINT APPLICATION................................................................................................. 1-2

1-2 TAIL CIRCUIT APPLICATION (SpectraComm SHELF)................................................................ 1-2

1-3 TAIL CIRCUIT APPLICATION (OCM SHELF) ..............................................................................1-3

2 —INSTALLATION

2-1 STANDALONE COVER REMOVAL PROCEDURE ........................................................................2-1

2-2 BASE CARD AND PLUG-IN CARD OPTION LOCATION AND SELECTION (3 Sheets).............2-4/5

2-3 DE-27E STANDALONE ENCLOSURE REAR PANEL.................................................................... 2-10

2-4 DE-27 STANDALONE ENCLOSURE REAR PANEL ......................................................................2-11

2-5 DataComm AND UNIVERSAL SYSTEM SHELF REAR PANEL CONNECTIONS.......................2-12

3 — OPERATION

3-1 FRONT PANEL INDICATORS....................................................................................................... 3-2

3-2 FRONT PANEL CONTROLS.......................................................................................................... 3-3

4 — TESTS

4-1 FAULT ISOLATION SEQUENCE.................................................................................................... 4-2

4-2 LINE LOOPBACK TEST...................................................................................................................4-4

4-3 DIGITAL LOOPBACK TEST............................................................................................................4-6

4-4 REMOTE LOOPBACK TEST........................................................................................................... 4-8

4-5 REMOTE LOOPBACK SELF TEST................................................................................................. 4-9

4-6 END-TO-END SELF TEST ...............................................................................................................4-11

4-7 NETWORK LOOPBACK TEST, EOC CONTROLLED................................................................... 4-13

i i i

LIST OF TABLES

Section &Tables Page

1 — INTRODUCTION

1-1 EQUIPMENT LIST........................................................................................................................... 1-4/5

2 — INSTALLATION

2-1 OPTION APPLICATION NOTES ...................................................................................................2-7

4 — SECTION NAME

4-1 DIAGNOSTIC TEST PRIORITIES...................................................................................................4-1

iv

INDEX

AC power cord, 2-9 Installation procedures, 2-1Applications, 1-2/3 Operating procedures, 3-1Business equipment connections, 2-8 Plug-in cards, 2-3, 4Business equipment interfaces, B-1, C-1 Preoperational check, 2-13ITU-T V.35 interface, C-1 Service and training, 4-14, 15Communications line, 2-9 Technical characteristics, A-1DataComm shelf, 2-15 Tests, 4-1DDS/VF line connections, 2-12 End-to-end self test, 4-10Description, 1-1 Line loopback (LL), 4-3Diagnostic circuits, 4-1 Digital loopback test, 4-5Diagnostic test priorities, 4-1 Remote loopback test, 4-7ITU-T V.24/V.28 interface, B-1 Remote loopback self-test, 4-10Electrical connections Network Loopback test, EOC controlled, 4-14

Rackmount shelf, 2-8 Universal system shelf, 2-12Standalone enclosure, 2-8

Equipment list, 1-4Features, 1-1Options, 2-2, 3, 4Front panel, 3-1

SECTION 000R000-X

PATENT NOTICE

ANALOOP® is a patented method and apparatus of General DataComm, Inc. (U.S. Patent 3,655,915).

DATALOOP® is a patented method and apparatus of General DataComm, Inc. (U.S. Patent 3,769,454).

TRADEMARK NOTICE

and the following are Trademarks of General DataComm, Inc.®

ACCULINE® LAN*TMS®

ANALOOP® MACROMUX® (Canada Only)AUTOFRAME® MEGA*BRIDGE®

BERT 901® MEGAMUX®

DATACOMM SECURE-PAK® MEGAMUX TMS®

DATALOOP® MEGANET®

DATX® (Canada Only) MEGASPLIT®

DATX SWITCHING SYSTEM® (Canada Only) MEGASWITCH®

DIGIDIAL® MEGAVIEW®

FIRST RESPONSE® MULTIMODEM®

GDC® NETCON®

GDC APEX™ NETSWITCH®

GENERAL DATACOMM® NMC®

GENERAL DATACOMM X-PRESS 24® NMS® (Canada Only)GEN*NET® QUIKSHIPPERS®

GEN*PAC® SERVI-CHECK®

IMAGE*TMS™ SERVI-SNAP®

KILOMUX® STATKAT® ( Canada Only)V.FAST™

GENERAL DATACOMMUNICATIONS INDUSTRIES & DESIGN® (UK Only)

WARRANTY NOTICE

WARRANTIES: General DataComm, Inc. (hereafter referred to as GDC), warrants that its equipment isfree from any defects in materials and workmanship. The warranty period shall be one year from the dateof shipment of equipment. GDC's sole obligation under its warranty is limited to the repair or replacementof the defective equipment provided it is returned to GDC, transportation prepaid, within a reasonable period.This warranty will not extend to equipment subjected to accident, misuse, or alterations or repair not madeby GDC or authorized by GDC in writing. THE FOREGOING WARRANTY IS EXCLUSIVE AND IN LIEUOF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,WARRANTIES OF MERCHANTABILITY AND FITNESS FOR PURPOSE.

X-6

SECTION 1

INTRODUCTION

INTENDED USERS This manual is intended for technical personnel with training and/orexperience installing and operating network or communicationsproducts.

FEATURES • 610 NTU supports a single channel (64Kbps or 128 Kbps) of customerdata on a two-wire 2B1Q loop circuit.

• 612 NTU supports two 64 Kbps channels or a single 128 Kbps channelof customer data on a two-wire 2B1Q loop circuit.

• Hardware configurable via on-board switches.

• May be used as a Network Managed Element when used within aGDC Network Management System.

• V.35 and ITU-T V.24/V.28 interfaces are provided for each DTE port.

• Compatible with ANSI 2B+D, B1 and B2 loopbacks.

• Supports both V.54 and PN127 loopbacks.

PRODUCTDESCRIPTION

The DataComm 610 and DataComm 612 are single channel and dualchannel Network Terminating Units (NTUs). They are compatible withANSI T1.601-1992 line coding requirements and support an operatingrange of up to 18 kilo feet over a two-wire 26 gauge line.

V.35 and ITU-T V.24/V.28 interfaces are on board selectable through berg-style jumpers. Optional 530 or X.21 interface cards are available.

You can option the 610 and 612 from the base card or remotely controlledusing a GDC Network Management System. You may use the TMSController when using the 610 or 612 in conjunction with a BQM card,and the HP OPENVIEW/PC Manager when using the NTU inconjunction with a SpectraComm 616.

The 610/612 are available in standalone and rackmount versions. Therackmount versions feature GDC's unique DataComm or UniversalSystem Shelf packaging concept. You can mount a variety of datacommunications products including up to 16 NTU's in the same highdensity shelf. Refer to Table 1-1 for a list of part numbers for standardand optional equipment for the 610 and 612. Appendix A describestechnical characteristics.

1-1

INTRODUCTION

APPLICATIONS Figure's 1-1 through 1-3 describe some applications for the NTU's.

Point-to-Point (Hard optioning only) - There is no soft optioningavailable. You may generate diagnostic tests from the front panelswitches or DTE interfaces.

2B1QDTE 2'

DTE 1'610/612

610/612DTE 2

DTE 1

FIGURE 1-1. POINT-TO-POINT APPLICATION

Tail Circuit (SpectraComm Shelf) - Shows the 610 NTU's as tailcircuits of a SpectraComm Shelf. The SCM (SpectraComm Manager) willhave soft control of the 610 or 612 in this application.

610/612

610DTE 1 (128 Kbps)

2B1QSpectraComm 616

SCM

SpectraComm Shelf

G.70364 Kbps

G.70364 Kbps

610/612

610/612

DTE 1 (64 Kbps)

DTE 2 (64 Kbps)

DTE 1 (64 Kbps)

DTE 2 (64 Kbps)

DTE 1 (64 Kbps)

DTE 2 (64 Kbps)

SpectraComm 6162B1Q

610/612

610/612

DTE 1 (64 Kbps)

DTE 2 (64 Kbps)

DTE 1 (64 Kbps)

DTE 2 (64 Kbps)

FIGURE 1-2. TAIL CIRCUIT APPLICATION (SpectraComm SHELF)

1-2

INTRODUCTION

Tail Circuit (OCM Shelf) - This application shows the 610 NTU's astail circuits of an OCM. You may control the 610 from the TMSController.

610

BQM

BQM

LIM

2B1Q 2B1Q

DTE 1 DTE 2

128 Kbps64 Kbps64 Kbps

OCM Shelf

610/612

FIGURE 1-3. TAIL CIRCUIT APPLICATION (OCM SHELF)

DIAGNOSTICS The 610 and 612 NTU's incorporate built-in diagnostic circuits to allowquick and thorough performance tests. The diagnostic testing capabilitiesinclude standard B1, B2 and 2B+D loopbacks, V.54 and PN127 compliantRemote Loopback (RL) and Self Test. The Self-Test feature contains adual-patterned generator and receiver that reduces the need for externaltest equipment. The built-in RL capability allows looping of data from oneor both data channels back from a remote site to the originating location.This loopback capability works with 610 and 612 pairs, or a SpectraComm616.

SERVICE ANDTRAINING

See Section 4 for information on service and training available fromGDC.

1-3

INTRODUCTION

TABLE 1-1. EQUIPMENT LIST

Description Part No.610 Standalone, V.35, 117 Vac 048A080-001610 Standalone, V.35, 220 Vac 048A080-002610 Standalone, V.35, 240 Vac 048A080-004610 Standalone, ITU-T V.24/V.28, 117 Vac, 048A080-011610 Standalone, ITU-T V.24/V.28, 220 Vac, 048A080-012610 Standalone, ITU-T V.24/V.28, 240 Vac, 048A080-014612 Standalone, V.35 X2, 117 Vac 048A080-021612 Standalone, V.35 X2, 220 Vac 048A080-022612 Standalone, V.35 X2, 240 Vac 048A080-024612 Standalone, ITU-T V.24/V.28 X2, 117 Vac 048A080-031612 Standalone, ITU-T V.24/V.28 X2, 220 Vac 048A080-032612 Standalone, ITU-T V.24/V.28 X2, 240 Vac 048A080-034612 Standalone, V.35, ITU-T V.24/V.28, 117 Vac 048A080-041612 Standalone, V.35, ITU-T V.24/V.28, 220 Vac 048A080-042612 Standalone, V.35, ITU-T V.24/V.28, 240 Vac 048A080-044612 Standalone, ITU-T V.24/V.28, V.35, 117 Vac 048A080-051612 Standalone, ITU-T V.24/V.28, V.35, 220 Vac 048A080-052612 Standalone, ITU-T V.24/V.28, V.35, 240 Vac 048A080-054

Enclosures/ShelvesDE Cover 010D500-003Base Assembly, DE27, V.35, 117 Vac 010B144-001Base Assembly, DE27E, V.35, 220/240 Vac 010B180-005Base Assembly, DE27, ITU-T V.24/V.28, 117 Vac 010B145-001Base Assembly, DE27E, ITU-T V.24/V.28, 220/240 Vac 010B180-006Base Assembly, DE27, V.35 X2, 117 Vac 010B144-001Base Assembly, DE27E, V.35 X2, 220/240 Vac 010B180-001Base Assembly, DE27, ITU-T V.24/V.28 X2, 117 Vac 010B145-001Base Assembly, DE27E, ITU-T V.24/V.28 X2, 220/240 Vac 010B180-002Base Assembly, DE27, V.35, ITU-T V.24/V.28, 117 Vac 010B146-001Base Assembly, DE27E, V.35, ITU-T V.24/V.28, 220/240 Vac 010B180-003Base Assembly, DE27, ITU-T V.24/V.28, V.35, 117 Vac 010B147-001Base Assembly, DE27E, ITU-T V.24/V.28, V.35, 220/240 Vac 010B180-004

1-4

INTRODUCTION

TABLE 1-1. EQUIPMENT LIST (Cont.)

Enclosures/Shelves (Cont.)610 Rackmount 048P080-001612 Rackmount 048P080-002DataComm Shelf, DS-1, 117 Vac 010B015-001DataComm Shelf, DS-5R, -48 Vdc redundantpower supplies

010M011-001

DataComm Shelf, DS-5NR, -48 Vdc non-redundantpower supply

010M011-002

DataComm Shelf, DS-6R, -48 Vdc redundantpower supplies, NEBS-compliant dimensions

010M047-001

DataComm Shelf, DS-6NR, -48 Vdc non-redundantpower supply, NEBS-compliant dimensions

010M047-002

Universal Sytem Shelf USS-1-D, 117 Vac,Domestic

010B080-001

Universal Sytem Shelf USS-1-DC/NR, -48 Vdcnon-redundant power supply

010M040-001

Universal Sytem Shelf USS-1-DC/R, -48 Vdcredundant power supply

010M040-002

Optional Equipment25-pin Female to 34-pin Female (Shelf V.35 Business Equipment Channel 2) 027H566-X0625-pin Male to 25-pin Female (Shelf ITU-T V.24/V.28 Business Equipment Channel 1) 027H511-00125-pin Female to 25-pin Female (Shelf ITU-T V.24/V.28 Business EquipmentChannel 2)

028H515-X06

25-pin Male to 34-pin Female (Shelf V.35 Business Equipment Channel 1 orstandalone both channels)

070H002-001

Cable with Modular Connectors 830028-807,814, 825

Alternate Line Connection Cable 023H101-020530 Interface card 048P042-001X.21 Interface card 048P085-001

1-5

SECTION 2

INSTALLATION

UNPACKING ANDHANDLING

Inspect the unit for damage; if any is observed, notify the shipperimmediately. Save the box and packing material; you can use it to reshipthe unit, if necessary.

INSTALLATIONPROCEDURES

You may install the 610 and 612 basecard in a standalone DataCommEnclosure or rackmounted them in a DataComm or Universal SystemShelf (USS). Place the unit in a ventilated area where the ambienttemperature does not exceed 122°F (50°C). Do not install the unit directlyabove equipment that generates a large amount of heat (such as powersupplies).

StandaloneInstallation

If it is necessary to remove the component cards from the standalonebase, disconnect the power supply connector from J1 mounted at the rearcenter of the base card. When reinstalling the component cards to thebase, reinstall the connector at J1. Refer to Figures 2-1 and 2-2.

2 2

CAUTION: DISCONNECT POWER CABLE AND PHONE CONNECTIONS BEFORE REMOVING COVER.

WITH FRONT OF UNIT FACING LEFT, TURN SCREW TO RELEASE COVER.

LIFT RIGHT END OF COVER UPWARD. (FOR DUAL-CARD PRODUCTS, SPREAD OUT THE SIDES OF THE COVER TO CLEAR THE UPPER CARD.)

SLIDE COVER TO LEFT WITH AN UPWARD MOTION.

WHEN REINSTALLING COVER, TOP EDGE OF REAR PANEL MUST SIT BETWEEN THE TWO RIDGES ON UNDERSIDE OF COVER.

3

1

3

1

FIGURE 2-1. STANDALONE COVER REMOVAL PROCEDURE

2-1

INSTALLATION

RackmountInstallation

The 610 and 612 mounted in a DataComm Shelf (DS-1, DS-5 or DS-6)supports as many as 16 NTUs. Install the NTU in any unused slot in theshelf as follows:

1. Position the card in the top and bottom slot guides with the GDC logoon top, and carefully slide the assembly into the slot until it stops atthe rear connectors.

2. Push the front panel with both hands until the assembly mates withthe rear connectors.

The Universal System Shelf (USS-1) accommodates 16 NTUs. The USS-1uses harness cards and backplanes configured to occupy one card slot inthe shelf for each NTU.

The backplane assembly has a keyed tab. The tab mates with a slot that ispart of the shelf and prevents the backplane from being insertedincorrectly in the shelf.

Install the NTU in the USS-1 shelf, as follows:

1. Loosen the backplane screws and install the plug-in card from thefront of the shelf by sliding it into the card guides. Seat firmly intothe mating connectors on the backplane using both hands.

2. Tighten the backplane screws. This assures perfect alignment ofthe cards in the card guides and the mating connectors on thebackplane and allows for easy removal of the cards. Plug in the four-pin cable harness on the backplane adapter to the shelf powerconnector located directly above the backplane adapter.

OPTIONSELECTION

Dip switches and jumper straps on the NTU base card select the fieldoptions.

Figure 2-2 (Sheets 1 through 3) illustrates the location of each option andindicates the manner of selection. Table 2-1 lists the function andapplication of each option.

2-2

INSTALLATION

J1

TB1

1234

XA1J2

XA1J3

XA

1J4

XA

1J1

610

12345678

12345678

S1

12345678

SOFT CNTRLLTU

EXT TIMINGMTXC=XTC2FP INHIBIT

SMDBA1BA2

GEN

ERA

L

RATE 0RATE 1RATE 2

RTS ONRTS INBAND

CTS DELAYANTISTREAM

511 PATT

CH

AN

NEL 1

RL INHIBITRL TIMEOUT

PN127 RLEBCK1

S2S16

X20

S10

LLERLETME

OP

EN

COM

SEP X4

232V.35

Interface Card(Solder Side)

Chan 1

FIGURE 2-2. BASE CARD AND PLUG-IN CARD OPTION LOCATION AND SELECTION(Sheet 1 of 3)

2-3

INSTALLATION

12345678

12345678

J1

TB1

S1

S2S16

X20

XA1J2

XA1J3

XA

1J4

XA

1J1

S10

XA1J2

XA1J3

XA

1J4

XA

1J1

S15

S17

612

1234

12345678

12345678

SOFT CNTRLLTU

EXT TIMINGMTXC=XTC2FP INHIBIT

SMDBA1BA2

GEN

ERA

L

RATE 0RATE 1RATE 2

RTS ONRTS INBAND

CTS DELAYANTISTREAM

511 PATT

RL INHIBITRL TIMEOUT

PN127 RLEBCK1

CH

AN

NEL 1

RATE 0RATE 1RATE 2

RTS ON

CH

AN

NEL 2

RTS INBANDCTS DELAY

ANTISTREAM511 PATT

RL INHIBITRL TIMEOUIT

PN127 RLEBCK2

LLERLETME

LLERLETME

OP

EN

COM

SEP

Interface Card(solder side)

X4X12232V.35

232V.35

Interface Card(solder side)

Chan 1

Chan 2


2-4

INSTALLATION

1 SOFT CNTRL Selects Soft Control (via EOC) of the NTU's options. (Default is Hard Switch Control.)2 LTU Selects LTU (master) operation. (Default is NTU [slave] operation.)3 EXT TIMING Selects External clock source for Master transmit timing. (Default is External clock

source.)GeneralUse

4 MT XC = XTC2 Selects Channel 2 External Transmit Clock as source of Master Transmit timing. Validonly when LTU operation and External clock source are selected. (Default is Channel 1XTC is source of Master transmit timing.)

5 FP INHIBIT Disables Front Panel Pushbutton test switches. (Default is FP switches Enabled.)6 SMD Reserved For Future Use.7 BA1 Selects byte alignment for Channel 1. (Default is no byte alignment).8 BA2 Selects byte alignment for Channel 2. (Default is no byte alignment).

Chan1 1 RATE 0 Selects 128 Kbps channel data rate. (Default is 64 Kbps.)Chan1 2 RATE 1 Reserved for future use. MUST REMAIN IN "OFF" POSITION.Chan1 3 RATE 2 Reserved for future use. MUST REMAIN IN "OFF" POSITION.Chan1 4 RTS ON Forces RTS ON. (Default is RTS to CTS delay determined by CTS DELAYChan1 5 RTS INBAND Enables inband signalling of RTS to drive a remote unit's DCD. (Default is Inband RTS

Disabled.)Chan1 6 CTS DELAY Selects 45 ms RTS to CTS delay. (Default is no RTS to CTS delay.)Chan1 7 ANTISTREAM Enables Antistreaming of RTS. (Default is Antistreaming Disabled.) Reserved For Future

Use.Chan1 8 511 PATT Selects 511 Self-Test pattern. (Default is 2047 Pattern.)

Chan1 1 RL INHIBIT Disables Remote Loopback Test. (Default is RL Enabled.) (Inhibits RL send andreceive).

Chan1 2 RL TIMEOUT Selects 10 minute RL timeout. (Default is no RL timeout.) (Timeout on send only).Chan1 3 PN127 RL Selects PN127 -type Remote Loopback. (Default is V.54-type RL).Chan1 4 EBCK1 Selects external buffer clock. (Default is internal buffer clock).Chan 2 5 RATE 0Chan 2 6 RATE 1 SAME AS CHANNEL 1Chan 2 7 RATE 2Chan 2 8 RTS ON

Chan 2 1 RTS INBAND Reserved for future use.Chan 2 2 CTS DELAYChan 2 3 ANTISTREAMChan 2 4 511 PATT SAME AS CHANNEL 1Chan 2 5 RL INHIBITChan 2 6 RL TIMEOUTChan 2 7 PN127 RLChan 2 8 EBCK2


2-5

INSTALLATION

TABLE 2-1. OPTION APPLICATION NOTES

Switch (S) or Primary ChannelOption Jumper (X) Description

GroundsX20 This option provides separation or connection of pro-

tective and signal grounds. Separation of grounds (by100 ohms or open) is selected with consideration givento power line noise, differences in ground potential,DTE manufacturer's recommendations, and safetyrequirements. Direct connection reduces the effects oflongitudinal power line noise.

Soft Control S1-1 When ON, the NTU is configured and controlled from aGDC Network Management Controller and the rest ofthe option switches will NOT be operable. When OFF,the NTU is optioned through the hardware switches.

LTU S1-2 When ON, the unit will operate as a LTU which providestiming to the circuit and handshake initiation. WhenOFF, the unit operates as a NTU, which recoverstransmit timing from a LTU.

External Timing S1-3 When in the LTU mode, the unit will generate an internalclock for the transmit timing. When ON in the LTUmode, the unit will use the external clock provided onport 1 or port 2 (612 only) for transmit timing. The NTUmode defaults to internal timing.

Master Transmit Clock S1-4 When ON and external timing is selected, the mastertransmit clock is derived from port 2. When OFF andexternal timing is selected, the master transmit clock isderived from port 1. NOTE: This option is valid only forthe 612. Must be left OFF (Default) for 610.

Front Panel Inhibit S1-5 When ON, the front panel test switches (LL, RL, ST,DL) are inhibited. When OFF, the front panel testswitches are enabled.

Simulated Multi-drop S1-6 Reserved for future use.Byte Alignment 1 S1-7 This option must be selected when using an interface

card that requires byte alignment on channel 1; i.e.X.21. When OFF, no byte alignment is performed.

Byte Alignment 2 S1-7 This option must be selected when using an interfacecard that requires byte alignment on channel 2; i.e.X.21. When OFF, no byte alignment is performed.

Rate 0 S2-1 (Chan 1)S16-5 (Chan 2)

When ON, 128Kbps data rate is configured for thechannel. When OFF, the channel rate is 64Kbps.

Rate 1, Rate 2 S2-2,3 (Chan 1)S16-6,7 (Chan 2)

Reserved for future use. MUST BE SET "OFF" (Default).

2-6

INSTALLATION

TABLE 2-1. OPTION APPLICATION NOTES (Cont.)Switch (S) or

Option Jumper (X) DescriptionRTS ON S2-4 (Chan 1)

S16-8 (Chan 2)When ON, the Request-to-Send (RTS) signal is forcedon. When OFF the RTS -to-CTS delay is determined bythe CTS Delay option.

RTS Inband(Reserved for future use.)

S2-5 (Chan 1)S15-1 (Chan 2)

When ON, the local RTS signal drives the remote unit'sCarrier Detect (CD) signal. When OFF, RTS is notmapped into the remote CD signal. This option MUST beconfigured the same at both ends of the network.

CTS Delay S2-6 (Chan 1)S15-2 (Chan 2)

When ON, the RTS to CTS delay will be 45 ms. WhenOFF, the RTS to CTS delay will be 0 ms.

Antistream S2-7 (Chan 1)S15-3 (Chan 2)

Reserved for future use.

511 Pattern S2-8 (Chan 1)S15-4 (Chan 2)

When ON, a 511 pattern will be used for all self-testpattern generation and checking. When OFF, a 2047pattern will be used.

Remote Loopback Inhibit S16-1 (Chan 1)S15-5 (Chan 2)

When ON, the NTU will not respond to, or generate RLsignals. When OFF, RL signalling will operate normally.

Remote Loopback Timeout S16-2 (Chan 1)S15-6 (Chan 2)

When ON, a 10 minute remote loopback will be selected.When OFF, there will be no timeout.

PN 127 Remote Loopback S16-3 (Chan 1)S15-7 (Chan 2)

When ON, PN 127 will be the method used to perform theremote loopbacks. When OFF, V.54 will be the methodused.

External Buffer Clock S16-4 (Chan 1)S15-8 (Chan 2)

When ON, and the timing source is Internal or Network,the input clock to the elastic buffer is the DTE clock(External). When OFF, the input clock to the buffer is theunit's transmit timing. When the timing source isExternal, the buffer clock is always the DTE clock.

Local Loopback Enable S10-1 (Chan 1)S17-1 (Chan 2)

When ON, a local loopback (towards the DTE) may becontrolled by the DTE (pin 18 of the ITU-T V.24/V.28interface or pin J of the V.35 interface). When OFF, theLL test is not under DTE control.

Remote Loopback Enable S10-2 (Chan 1)S17-2 (Chan 2)

When ON, a remote loopback may be controlled by theDTE (pin 21 of the ITU-T V.24/V.28 interface or pin BB ofthe V.35 interface). When OFF, the RL test is not underDTE control.

Test Mode Enable S10-3 (Chan 1)S17-3 (Chan 2)

When ON, the NTU will signal a test condition to the DTE(pin 25 of the ITU-T V.24/V.28 interface or pin K of theV.35 interface). When OFF, no test mode indication willbe given to the DTE.

2-7

INSTALLATION

ELECTRICALCONNECTIONS

The following paragraphs describe the power line, business equipment,and line connections to the 610 and 612.

Power - StandaloneEnclosure

Attach the appropriate power cord to the rear panel IEC connector or thewall receptacle (depending on the base assembly you ordered). The outletshould not be under switch control. You should power the unit by the sameac source as the equipment interfaced with the unit to prevent largecirculating currents caused by differences in ground potential. If youcannot determine whether the equipment is powered by the same acsource, verify that a potential difference of less than 0.25 V rms existsbetween the grounding circuits of the respective power outlets.

Power - RackmountShelf

The NTU obtains power directly from the shelf when properly installedas instructed under Rackmount Installation.

BusinessEquipment

ConnectionsYou can make Business Equipment connections to the standalone using avariety of connectors depending on the base assembly that was ordered.(see Figures 2-3 and 2-4). Figure 2-5 shows the connections to therackmount shelf.

NOTE

You may find that single channel versions have a blankcover at the Business Equip 2 connector location.

530 or X.21Interface Card

ConnectionsThe optional 530 or X.21 Interface Cards provides these interfaces for theDTE. They are available factory installed, or as a field upgrade kit.They plug into the base card as illustrated in Figure 2-2. (You can alsoremove the card(s) and place jumpers on XA1J2 and XA1J3 to make thebase card interface active.) When you install the optional 530 or X.21Interface Card in the active position, DTE control of Remote TerminalTest and Local Loopback is unsupported.

NOTE

You may strap jumper's X4 and X12 on the 612 and X4 onthe 610 to either 232 or V.35 by removing the optional plug-in card, and return the jumpers to the base card.

Appendixes B through E describe the signals exchanged through each ofthe business equipment interfaces.

2-8

INSTALLATION

Line ConnectionsWhen the NTU is installed in the standalone enclosure, it is connected tothe communications line using the terminal block located on thebasecard. When using the TB1 terminal connections, the two-wire privateline is brought through the access hole on the enclosure's rear panel andconnected to the two center terminals (2 and 3) on the base card as shownin Figures 2-3 and 2-4.

If the NTU is rackmounted in the DataComm Shelf (DS-1, DS-5 or DS-6),the two-wire private line is connected to the top two screws (T and R) ofthe terminal block mounted on the shelf's rear panel. If the unit ismounted in the Universal System Shelf (USS-1D or USS-1DC), the plasticcover attached at the rear of the backplane must first be removed to exposethe terminal blocks. These blocks accommodate wires that do not haveterminal lugs. Remove the lugs and a portion of the insulation from theexisting cable and insert the wires into the block by first unscrewing thecaptive screw for that portion of the terminal. Connect the two wires toT/T and R/R, and replace the plastic cover. (See Figure 2-5).

In either case, before making the connection, verify that the terminalblock corresponds to the shelf receptacle in which the NTU card isinstalled.

2-9

INSTALLATION

Business Equip 1

Auxiliary 1

Business Equip 2

Auxiliary 2

023H101-020

COVER COVER

GREEN RED

240

120

230 100

240V~ 50-60Hz0.1A Fuse T 0.125A

20V~ 50-60Hz 0.1A Fuse T 0.125A

10V~ 50-60Hz0.2A Fuse T 0.25A

NOTE:These connector slots may be populated with a combination of connectors depending on base assembly ordered:

DB-25

V.35

BLANK COVER

FIGURE 2-3. DE-27E STANDALONE ENCLOSURE REAR PANEL

2-10

INSTALLATION

Business Equip 1

NETWORK

Auxiliary 1

Business Equip 2

Auxiliary 2J2

023H101-020

COVER COVER

GREEN RED

DB-25

V.35

BLANK COVER

NOTE:These connector slots may be populated with a combination of connectors depending on base assembly ordered:

FIGURE 2-4. DE 27 STANDALONE ENCLOSURE REAR PANEL

2-11

INSTALLATION

MODULAR CONNECTIONS

BUSINESS EQUIPMENT 2 CONNECTION

CABLE NOS.830028-825 (25 Ft.)830028-814 (14 Ft.)830028-807 (7 Ft.)

CABLE NO. 023H101-020 (SEE NOTE)

NOTE: Connect red and green , or black and yellow wires to terminals T and R. Tie back the two unused wires.

T / TR/RPC/DTPR/DRMIC/TEK 5MIC/TEK 6

DS-1 DataComm Shelf Rear Panel USS-1 Universal System Shelf Rear Panel

12

34

56

FIGURE 2-5 DataComm AND UNIVERSAL SYSTEM SHELF

REAR PANEL CONNECTIONS

2-12

INSTALLATION

PreoperationalCheck

You can give the 610 and 612 a preoperational check by performing a LineLoopback (see Section 4, Tests). Verify the factory option strapping is inthe OFF position (see Figure 2-2, Sheet 2). With power connected, performthe test on a standalone NTU. Perform the test on a DataComm Shelf,upon installation of each card.

If the NTU passes the test, but subsequently fails to perform datacommunications, the NTU is probably not at fault. An error exists in theinstallation or options selection made, or there is a faultycommunications line or remote installation. Recheck the cable and lineconnections and, if necessary, perform the tests in Section 4 to isolate theproblem. Verify that the remote NTU is a compatible type (e.g., a NTUoperating at the correct data rate). If the NTU does not check out properly,replace it with a spare NTU, and repeat the test. Do not attempt to repairthe NTU. For assistance, contact DataComm Service Corporation (seeSection 4).

2-13

SECTION 3

OPERATION

OVERVIEW

When you install the 610 and 612 NTUs properly, control is automatic.They have no operating instructions (except for test procedures given inSection 4, Tests). This section describes the controls and indicators of theunit so that the operator may use to check the operation of the NTU.

CONTROLS,INDICATORS AND

CONNECTORS

Figure's 3-1 and 3-2 illustrate the NTU's front panel and explain thefunction of each control and indicator. You can find illustrations of theshelf and standalone rear panel connectors in Section 2.

RACKMOUNTSHELF

You can find a description of the rackmount shelf front panel controls,indicators and fuses in the manual supplied with the shelf. Refer to it ifyou have a rackmount shelf. Figure 2-7, shows the shelves rear panel andconnectors.

3-1

OPERATION

612

ON

SY

NC

LL

CH

1

CH

2

SD

RD

RS

CS

CO

TM

CH

SE

LS

TR

LD

L

610

ON

SY

NC

LL

SD

RD

RS

CS

CO

TM

ST

RL

DL

CH

AN

NE

L

On to indicate the channel which the ST, RL, and DL switches control.

On when the NTU is in a test mode and blinks off (for approx. 200 ms) when a bit error has been detected during a self-test.

On when the NTU is in sync and is receiving data. Off during self-test (ST).

On when the NTU is ready to send data.On when the DTE is ready to send data. Also on during RDL test and self-test modes and when RTS ON option is enabled.

On when received data is positive (space).On when a space bit is present in send data.

Normally on. Off if power is lost.

On when the NTU network has network synchronization. Off when synchronization is lost.

NOTE: 612 indicator functions are shown. 610 indicator functions are the same.

On when the NTU is in sync.Off during self-test (ST), digital loopback (DL), and while unit is initiating a remote loopback.

FIGURE 3-1. FRONT PANEL INDICATORS

3-2

OPERATION

612

ON

SY

NC

LL

CH

1

CH

2

SD

RD

RS

CS

CO

TM

CH

SE

LS

TR

LD

LDepressing this switch will cause the NTU test pattern generator to generate and check a self-testpattern.

Depressing this switch places both channel 1 and channel 2 into a Bi-lateral loopback.

NOTE: 612 is shown. 610 front panel switch functions are the same with the omission of SEL.

Depressing this switch will cause the NTU to operate a Digital Loopback of the selected channel.

Depressing this switch will cause a remote unit to operate a Digital Loopback of the selected channel.

Channel Select:Depressing this switch toggles control of the ST, RL, and DL front panel switches between channel 1 and channel 2.(cannot change channel selection during diagnostics.)

FIGURE 3-2. FRONT PANEL CONTROLS

3-3

SECTION 4

TESTS

OVERVIEW This section describes tests you can perform from the front panel.Figures' 4-2 through 4-7 show the 612 front panel. The 610 performs thesame tests without the SEL front panel pushbutton. Table 4-1 describes thediagnostic test priorities. You can use the tests described in this section toisolate problems in the data communications system (refer to the fault-isolation sequence in Figure 4-1).

TABLE 4-1. DIAGNOSTIC TEST PRIORITIES

CHANNEL 1 OR CHANNEL 2Priority Test Means of Activation

1 2B+DB1, B2 Loops

Network Control Code

2 LL Front Panel (FP) Switch3 DL Front Panel (FP) Switch4 RL Front Panel (FP) Switch5 LL DTE6 RL DTE7 ST Front Panel (FP) Switch8 RL (Remote) From Remote RL

NOTES:

1. PN127 RL tests are attempted once and are not repeated.

2. V.54 are repeated until the loop is achieved or the test isaborted.

3. Front panel ST test cannot be combined with a DTEinitiated LL or RL.

4. You can perform Diagnostics independently on Channel 1or Channel 2, but may not be initiated from the front panelat the same time (612 only).

5. You may initiate Diagnostics from the front panelswitches, the DTE interface, or the Network.

6. The SD and RD test indicators referred to in the testsdescribed in this section, may flicker (blink) or appear to besolidly ON. This will depend on the data rate at which theunit is being tested. They may not appear as bright as otherLED indicators.

4-1

TESTS

POINT-TO-POINTTESTING

The following paragraphs present test information for point-to-pointinstallations. You may option the NTU to permit the DTE to control LocalLoopback and Remote Loopback (Refer to Section 2, Installation).

FIGURE 4-1. FAULT ISOLATION SEQUENCE

4-2

TESTS

LINE LOOPBACKTEST

Line Loopback (LL) checks the performance of the 610 and 612 and itsassociated DTE (s). You may perform this test for Channel 1 andChannel 2. Initiating this test, the NTU transmitter output and receiverinput disconnects from the communications line and connects, creatinga circuit similar to an analog loopback circuit that loops signals from thetransmitter through the receiver. Also, the disconnected transmitter andreceiver communications lines connect, creating a circuit (the LineLoopback circuit) that loops received signals back over thecommunications line to the originating station. Figure 4-2 illustrates LLusing the front panel LL pushbutton.

While Line Loopback is being performed locally, you may send a Self-Test pattern from the remote site to the local NTU, which loops the testpattern back to the remote site for verification. This test will check theperformance of the remote site's DSU and the communications line. Toperform this test, arrange with the remote site personnel before initiatingLine Loopback Self-Test locally.

4-3

TESTS

NETWORK

NOTE:Channel 2 is also looped on the 612.

CHANNEL 2

612 ON SYNCLL

CH1

CH2

SD RD RS CS CO TM CH SEL ST RL DL

LOCALLOOP

1. Engage pushbuttn LL. 2. TM should light.

3. Initiate a test message from the DTE. This may be done by typing a message on

the DTE keyboard.

4. SD/RD leds will light with transmit/receive data. An exact copy of test message should be received at DTE.

FIGURE 4-2. LINE LOOPBACK (LL) TEST

4-4

TESTS

DIGITALLOOPBACK TEST

This Digital Loopback (DL) test checks the performance of the local andremote NTU's, the local unit's DTE and the communications line. Whenthe test is initiated, the unit's receiver output and the transmitters inputare disconnected from the DTE and connected together, creating a circuitthat loops back the remote unit's transmit data. Figure 4-3 illustrates theDL test.

4-5

TESTS

NOTE: TEST PROCEDURES DESCRIBED HERE ARE THE SAME FOR CHANNEL 2.

612 ON SYNCLL

CH1

CH2


1. Initiate this test by engaging RL at local unit.

3. RS and CS OFF and TM ON at the remote unit.

4. Initiate a test message from the DTE at the local unit by typing a message on the DTE keyboard.

5. SD and RD blink at the local unit. RD is OFF at the remote unit.

2. RS, CS, CO and TM light ON at the local unit.

6. An exact copy of the test message should be received at the originating DTE.

7. To end the test, disengage RL at local unit.

2B1QDATAPUMP

DTEINTER-FACE

TXLOGIC

RXLOGIC TDM

CHANNEL 2 - 612

DTEINTER-FACETX

LOGIC

RXLOGIC

TDM2B1QDATAPUMP

CHANNEL 2 - 612

NETWORK

LOCAL UNIT

REMOTE UNIT

FIGURE 4-3. DIGITAL LOOPBACK TEST

4-6

TESTS

REMOTELOOPBACK

Remote Loopback (RL) checks the performance of the local and remoteunit's, the local DTE, and the communications line. When you initiatethis test, the remote unit goes into a Digital Loopback (DL) condition. Theremote unit transmitter and receiver are disconnected from the DTEinterface and connected together, creating a circuit that loops thereceiver's digital output signals to the transmitter's input. Figure 4-4illustrates RL.

4-7

TESTS

NOTE: TEST PROCEDURES DESCRIBED HERE ARE THE SAME FOR CHANNEL 2.

612 ON SYNCLL

CH1

CH2


1. Initiate this test by engaging RL at local unit.

3. RS and CS OFF and TM ON at the remote unit.

4. Initiate a test message from the DTE at the local unit by typing a message on the DTE keyboard.

5. SD and RD blink at the local unit. RD is OFF at the remote unit.

2. RS, CS, CO and TM light ON at the local unit.

6. An exact copy of the test message should be received at the originating DTE.

7. To end the test, disengage RL at local unit.

2B1QDATAPUMP

DTEINTER-FACE

TXLOGIC

RXLOGIC TDM

CHANNEL 2 - 612

DTEINTER-FACETX

LOGIC

RXLOGIC

TDM2B1QDATAPUMP

CHANNEL 2 - 612

NETWORK

LOCAL UNIT

REMOTE UNIT

FIGURE 4-4. REMOTE LOOPBACK TEST

4-8

TESTS

612 ON SYNCLL

CH1

CH2


1. Engage RL on the local unit.

3. TM should be on during the test. If local TM turns off frequently, there may be a problem in the local unit, the remote unit, or the communications line.

4. End the test by disengaging ST then RL at the local unit.

2. After TM lights, engage ST on the local unit.

FIGURE 4-5. REMOTE LOOPBACK SELF TEST

4-9

TESTS

END-TO-END SELFTEST

In addition to using the Self-Test function in conjunction with other testfeatures, Self-Test may be used independently. In this test, the local andremote unit's exchange Self-Test patterns between their respective testcircuits to check the performance of the communications line and thelocal and remote unit's (not including the DTE interfaces). To performEnd-To-End Self-Test, proceed as shown in Figure 4-6.

4-10

TESTS

612 ON SYNCLL

CH1

CH2


1. Engage ST on the local unit. Direct attendant to engage ST at the remote unit.

2. TM should be on during the test. If local TM turns off frequently, there may be a problem in the local unit, the remote unit , or the communications line.

3. End the test by disengaging ST at both the local and remote units. TM should go OFF.

FIGURE 4-6. END-TO-END SELF TEST

4-11

TESTS

NETWORKLOOPBACK TESTS

(EOCCONTROLLED)

The Network Loopback tests (2B+D, B1 and B2) are remotely controlleddiagnostics that issues over the Embedded Operations Channel (EOC),loopback codes. The unit, which detects this code goes into loopback. Theunit's transmitter input and receiver output are disconnected from theDTE and are connected together to create a circuit that loops receivedsignals back over the communications line to the originating station.Figure 4-7 illustrates the EOC controlled Network Loopback tests.

When it is necessary to isolate a problem, contact the remote test centeroperator and ask them to initiate a network test. The test results should beused in conjunction with the fault isolation sequence (Figure 4-1) topinpoint a problem, if any.

NOTE

Remote controlled EOC tests can loop Channel 1 and/orChannel 2.

4-12

TESTS

NETWORK

NOTE:TEST PROCEDURES DESCRIBED HERE ARE THE SAME FOR CHANNEL 2 of the 612.

CHANNEL 2

612 ON SYNCLL

CH1

CH2


REMOTE TEST

CENTER

1. Contact the remote test center operator and ask them to initiate

a network loopback test.

2. TM will be lit during the test.

3. Use the test results in conjunction with Figure 4-1 to solve problems. If any,

coordinate with the remote test center operator to end the test.

FIGURE 4-7. NETWORK LOOPBACK TEST, EOC CONTROLLED

4-13

TESTS

TECHNICALASSISTANCEPROCEDURE

For technical assistance, customers should call DataComm ServiceCorporation at 203-598-7526.

In Canada:

General DataComm (Canada) Ltd.Service and Repair Facility1790 Beaulac StreetSt. Laurent, Montreal, Quebec H4R 1W8Telephone: 1-514-336-5454TWX: 610-421-3221Telex: 05824085

In the United Kingdom, contact the GDC area manager at:

General DataComm (U.K.) Ltd.Molly Millars CloseMolly Millars LaneWokingham, BerkshireEngland RG11 2QFTelephone: 011-44-734-774-868Telex: 851 847298Fax: 011-44-734-774-871

In Europe/Africa/Middle East:

General DataComm14, rue Jules SaulinierParc du Colombier, BP 22193200 ST DENIS, FranceTel: 011-33-1-48133470Fax: 011-33-1-42430021

In the Pacific:

General DataComm Pty.Suite 404275 Alfred Street NorthNorth Sydney, NSW 2060, AustraliaTel: 011-61-2-956-5099Fax: 011-61-2-956-5083

In Asia:

General DataComm401 Century Square1-13 D'Aguilar StreetCentral, Hong KongTel: 011-852-5265511Telex: 780-80579Fax: 011-852-5259944

4-14

TESTS

In Latin America:

General DataComm, International1579 Straits TurnpikeP.O. Box 1299Middlebury, Connecticut 06762-1299Telephone: 203-574-1118Telex: 7400905Fax: 203-758-9518

To return a unit for repair, if so authorized by GDC, use the return tagand address the package:

Product Repair DepartmentGeneral DataComm, Inc.1579 Straits TurnpikeP.O. Box 1299Middlebury, Connecticut 06762-1299

Lease and Maintenance contract customers may call DataComm ServiceCorporation toll-free at 1-800-243-1030, 24 hours a day, 7 days a week fortrouble reporting or installation scheduling. (Installations are normallyscheduled between 8 a.m. and 5 p.m.)

TRAINING Hands-on training courses are available from DataComm ServiceCorporation's Educational Services in the USA and in the UK. Coursesoffered range from basic data communications, modems and multi-plexers, to complex network systems, and are given at GDC’s Connecticutfacility or at a customer’s location.

For information call:

USA (203) 574-1118, Ext. 6190.UK 011-44-734-774-868

4-15

APPENDIX A

TECHNICAL CHARACTERISTICS

CPE INTERFACEData Rates 64Kbps or 128Kbps.Interface Types ITU-T V.24/V.28 or V.35. Can be used as an LDM in Metropolitan Area

Network (MAN) or campus networksNETWORK INTERFACE

Operating Mode Full duplex with adaptive echo cancellation.Data Rate 160 Kbps total: 128 Kbps user data, 16 Kbps internal control, 16 Kbps for

timing and synchronization.Data Format Synchronous, serial binaryLine Coding 2B1Q, compatible with ANSI T1.601Line Requirements 2-wire, non-loaded metallic circuitOperating Range 5.5 to 7 km (18,000 to 22,967 ft) — varies with wire size and bridged taps

DIAGNOSTICSNetwork 2B+D loopback

B1 loopbackB2 loopback

Customer (per channel) V.54 and PN 127 RL method (front panel and DTE invoked)LL (front panel bilateral and DTE channel loop only)DL (front panel invoked)

POWER REQUIREMENTSRackmount 10 W maximumHumidity Up to 95% without condensation

PHYSICAL CHARACTERISTICSStandaloneHeight 99 mm (3.9 in.)Width 277 mm (10.9 in.)Depth 318 mm (12.5 in.)Weight 3.2 kg (7.1 lbs.)Shipping Weight 3.6 kg (8.1 lbs.)Temperature 0° to 50°C (32° to 122°F) operating

–40° to 70°C (–40° to 158°F) non-operatingRackmount (Full shelf with 16 units)Height 267 mm (10.5 in.)Width 484 mm (19.0 in.)Depth 343 mm (13.5 in.) Also, 305 mm (12.0 in.) in DS-6 Enclosure.Weight 18 kg (40.2 lbs.)Shipping Weight 19 kg (42.5 lbs.)Temperature 0° to 50°C (32° to 122°F) operating

–40° to 85°C (–40° to 185°F) non-operatingFusing F1, F2: 2A, 250V, FBSafety Protection UL listed and CSA approved

A-1

APPENDIX B

BUSINESS EQUIPMENT (DTE) INTERFACE SIGNALS(ITU-T V.24/V.28)

P1, P2Pin

ITU-TNo.

Circuit Function

1 101 AA Shield2 103 BA Transmitted Data3 104 BB Received Data4 105/133 CA/CJ

(Note 1)Request to Send/Ready for Receiving

5 106 CB Clear to Send6 107 CC DCE Ready7 102 AB Signal Common8 109 CF Received Line Signal Detector9 - - (Reserved for Testing) (+12V)10 - - (Reserved for Testing) (-12V)11 126 (Note 2) Unassigned12 * 122/112 SCF/CI

(Note 3)Secondary Received Line Signal Detector/Data Signal RateSelector (DCE Source)

13* 121 SCB Secondary Clear to Send14* 118 SBA Secondary Transmitted Data15 114 DB Transmitter Signal Element Timing (DCE Source)16* 119 SBB Secondary Received Data17 115 DD Receiver Signal Element Timing (DCE Source)18 141 LL Local Loopback19* 120 SCA Secondary Request to Send20 108/1, /2 CD DTE Ready21 140/110 RL/CG Remote Loopback/Signal Quality Detector (RL for 610 and 612)22* 125 CE Ring Detector23* 111/112 CH/CI

(Note 3)Data Signal Rate Selector (DTE/DCE Source)

24 113 DA Transmit Signal Element Timing(DTE Source)25 142 TM Test Mode* Not supported in 610 and 612NOTES PERTAINING TO ITU-T V.24/V.28 TABLE

1: When hardware flow control is required, Circuit CA may take on the characteristics of Circuit CJ. (CA is used for 610 and612).

2: Pin 11 is unassigned. It will not be assigned in future versions of ITU-T V.24/V.28. However, in international standardISO 2110, this pin is assigned to ITU-T Circuit 126, Select Transmit Frequency.

3: ITU-T designations are shown for reference only.

B-1

APPENDIX C

BUSINESS EQUIPMENT (DTE) INTERFACESIGNALS (ITU-T V.35)

P1/P2Pin

V.35Pin

ITU-T(See Note) NTU Signal Description

1 A 101 Protective ground This circuit is connected to the equipment frame.Normally, it is separated from signal ground (pin B) by100 ohms, but it may be connected to signal groundby means of an option strap (X20).

7 B 102 Signal ground Establishes a common ground reference for allinterface circuits except protective ground, pin A.

4 C 105 RS Request-to-send Indicates to NTU that DTE is prepared to transmit.5 D 106 CS Clear-to-send Indicates to DTE that NTU is prepared to transmit.6 E 107 DM Data-set-ready Indicates to DTE that NTU is operational.8 F 109 CO Received line signal

detectorIndicates to DTE that NTU is receiving data (not idle orOOS codes).

25 K 142 TM Test mode Indicates to DTE that NTU in a test mode if optionswitch S10-3 or S17-3 is ON.

18 J 141 LLE Line loopbackenable

Transfers signal from DTE to control Line Loopbacktest mode if option switch S10-1 or S17-1 is ON.

214

PS

103103

SD-ASD-B

Transmitted data Transfers data signals from DTE for modulation andtransmission over communications line.

316

RT

104104

RD-ARD-B

Received data Transfers data signals received over communicationline and demodulated by NTU to DTE.

1224

UW

113113

TT-ATT-B

Transmitter timing(DTE source)

Transfers transmitter signal timing information fromDTE to NTU.

1317

VX

115115

RT-ART-B

Receiver timing Transfers receiver signal timing information from DSUto NTU.

1915

YAA/a

114114

ST-AST-B

Transmitter timing Transfers transmitter signal timing information fromNTU to DTE.

21 BB/b 140 Remote DigitalLoopback testenable

Transfers signal from DTE to control Remote Loop-back test mode if option switch S10-2 or S17-2 is ONand the NTU is an RDL-version.

20 H 108/2 TR Data TerminalReady

Indicates to NTU that DTE is prepared for datacommunication.

9 +12V Provided to Interface10 -12V Provided to Interface

NOTE: ITU-T designations are shown for reference only. M, N, CC, DD, FF, HH, JJ, KK, LL, MM, NN, Z, and Pins 23, 26 are not used.

C-1

APPENDIX D

BUSINESS EQUIPMENT (DTE) INTERFACESIGNALS (530)

P1/P2PIN

CircuitDesignation Signal Description

1 — Shield Allows shield connections.214

BA(A)BA(B)

Transmitted data Transfers data signals from DTE for modulation and transmis-sion over communications line.

316

BB(A)BB(B)

Received data Transfers data signals to DTE that were received over commu-nications line and demodulated by DSU.

419

CA(A)CA(B)

Request to send Indicates to DSU that DTE is prepared to transmit.

513

CB(A)CB(B)

Clear to send Indicates to DTE that DSU is prepared to transmit.

622

CC(A)CC(B)

Data set ready Indicates to DTE that DSU is prepared for data communica-tions.

2023

CD(A)CD(B)

Data terminal ready Indicates to DSU that DTE is prepared for data communica-tions.

7 AB Signal ground Establishes a common ground reference for all interface cir-cuits except protective ground.

810

CF(A)CF(B)

Received line signaldetector

Indicates to DTE that DSU is receiving data (not receiving idleor OOS codes).

1512

DB(A)DB(B)

Transmitter signal el-ement timing

Transfers transmitter signal timing information from DSU toDTE.

179

DD(A)DD(B)

Receiver signal ele-ment timing

Transfers receiver signal timing information from DSU to DTE.

18 LL Analog Loopback en-able

Transfers signal from DTE to control analog loopback test.

21 RL Remote DigitalLoopback enable

Transfers signal from DTE to control Remote Digital Loopbacktest mode.

2411

DA(A)DA(B)

Transmitter signal el-ement timing (ExternalClock)

Transfers transmitter signal timing information from DTE toDSU.

25 TM Test mode indicator Indicates to DTE that DSU is in a test mode .

D-1

APPENDIX E

BUSINESS EQUIPMENT (DTE) INTERFACESIGNALS (X.21)

P1/P2PIN

* 15-Pin X.21Connector

ITU-T CircuitDesignation Signal Description

214

29

T(A)T(B)

Transmitted data Data from DTE.

316

411

R(A)R(B)

Received data Data ro DTE.

419

310

C(A)C(B)

Control Indicates to DSU that DTE is prepared to transmit.

810

512

I(A)I(B)

Indication Indicates to DTE that DSU is receiving data.

179

613

S(A)S(B)

Signal elementtiming

Transmit and receive signal timing information from DSUto DTE.

2412

714

X(A)X(B)

B(A)B(B)

DTE signalelement timing(X) or Byte timing(B)

Optiional transmit signal timing information from DTE toDSU if X.21 adapter module is configured for XT. Bytetiming information from DSU to DTE if X.21 adapter moduleis configured for BT.

* DB25 to DB15 adapter cable, part # 027H436-001, needed for X.21 mechanical compatibility.

E-1

APPENDIX F

GLOSSARY

2B1Q Code Line code for basic rate ISDN at the "U" reference point.

Address A sequence of bits, a character, or a group of characters that identifies a networkstation, user, or application; used mainly for routing purposes.

AL Analog Loopback.

ANSI American National Standard Institute.

Analog Transmission employing variable and continuous waveforms to represent in-formation values.

Analog Loopback Technique for testing transmission equipment and devices that isolates faults tothe analog signal receiving or transmitting circuitry; a device, such as a modem,echoes back a received (test) signal that is then compared with the original sig-nal.

ANALOOP® General DataComm's version of Analog Loopback Test.

Asynchronous Transmission that is not related to a specific frequency or to the timing of thetransmission facility; transmission characterized by individual characters orbytes with start and stop bits from which a receiver derives the necessary timingfor sampling bits; start-stop transmission.

AsynchronousTransmission

Serial transmission of data in which each character is individually synchronizedby the use of start and stop bits. A start bit precedes and one or more stop bitsfollow continuous information bits. Also called start-stop transmission. There isno definite time relationship between transmission of successive characters.

Baud The maximum number of signaling elements, or symbols, per second that aregenerated; may be different from bps rate as several bits may be encoded persymbol, or baud, with advanced encoding techniques such as phase-shift keying.

BERT Bit Error Rate Test, or tester.

Bipolar The predominant signaling method used for digital transmission services, suchas T1, in which the signal carrying the binary value successively alternatesbetween positive and negative polarities. Zero and one values are represented bythe signal amplitude at either polarity, while no-value “spaces” are at zeroamplitude; also, polar transmission.

Bisynchronous A Binary Synchronous Communications protocol (BISYNC) that uses specialcharacters to define the various fields of a message and for control functions.Typically used for transmission between a CPU and a CRT or batch-type proces-sor. BISYNC accommodates a variety of transmission codes including ASCII,EBCDIC, and SBT (Six-Bit Transcode).

Bit A binary digit, the representation of a signal, wave, or state, as either a binaryzero or a one.

F-1

Bit Error Rate (BER) The percentage of received bits that are in error, relative to a specific amount ofbits received; usually expressed as a number referenced to a power of 10; e.g., 1 in

105.

Bps Bits per second; basic unit of measure for serial data transmissioncapacity; also kbps (kilobits), for thousands of bits per second; Mbps(megabits), for millions of bits per second; Gbps (gigabits), for billions ofbits per second; Tbps (terabits), for trillions of bits per second.

Buffer A storage device used to compensate for differences in the rate of data flow whentransmitting data from one device to another.

Byte Generally an 8-bit quantity of information, used mainly in referring to paralleldata transfer, memory capacity, and data storage; also generally referred to indata communications as an octet or character.

Carrier Detect An ITU-T V.24/V.28 Interface modem signal that indicates to the attachedterminal that a modem is receiving a signal from the remote modem.

ITU-T Designation for telecommunications recommendations written by theInternational Telecommunication Union (ITU); an internationaltelecommunication union agency involved in formulating internationalstandards for data communications. (Formerly CCITT - International Telegraphand Telephone Consultive Committee.)

Channel

Part of a circuit path through several entities in a communication system. Achannel runs between two nodes.

Character

Standard bit presentation of a symbol, letter, number, or punctuation mark.

One of several standard sets of binary representations for the alphabet, numerals,and common symbols, such as ASCII, EBCDIC, BCD.

Character Code

Character Oriented

Describing a communications protocol or transmission procedure that carriescontrol information encoded in fields of one or more bytes.

Clear To Send (CTS)

A signal indicating to the terminal that a modem is ready to transmit.

The time required by a modem to inform a terminal device that it is ready to sendor reply to information just received.

Clear To Send Delay

Clock

An oscillator-generated signal that provides a timing reference for a transmis-sion link; used to control the timing of functions as sample interval, signalingrate, and duration of signal elements; an “enclosed” digital network typicallyhas only one “master” clock.

Common Carrier

In the United States, any supplier of transmission facilities or services to the gen-eral public that is authorized to provide such facilities or services by the appropri-ate regulatory authority and bound to adhere to the applicable operating rules, suchas making services available at a common price and on a nondiscriminatory ba-sis.

Constant Carrier

Operation in which the Clear to Send signal from the modem to the terminal isheld permanently on and the modem's transmit carrier is always on. Carrierstays on independent of Request to Send from the data terminal; also continuouscarrier.

F-2

Control Characters Any transmitted characters, not message or user data, used to control or facilitatedata transmission between data terminal equipment (DTE); includes extra char-acters associated with addressing, polling, message delimiting and blocking,framing, synchronization, and error checking.

Controlled Carrier When Controlled Carrier is selected, the modem's transmit carrier is turned onand off by Request To Send (CA) from the terminal. The physical carrier signalis impressed on the line and the terminal is allowed to pass data after the ClearTo Send delay.

Convergence Display Oscilloscope display pattern from optional Constellation Pattern Generator whichindicates the rate at which the adaptive equalizer in the modem's receiver con-verges on received signals. This indication permits the identification of individ-ual malfunctioning remote stations or associated branch lines in multipoint net-works.

CS Clear To Send.

CTS Clear To Send.

Data Digitally represented information, which includes voice, text, facsimile, andvideo.

Data Carrier Detect(DCD)

A signal sent from a data set which informs the terminal that a carrier waveformis being received; also called Carrier Detected, Carrier Found, Carrier On, etc.

DataCommonality General DataComm's term to describe a unique packaging technique that pro-vides (1) high density modular packaging, (2) a broad array of versatile data setsand accessories, (3) system flexibility and ease of expansion, (4) low power con-sumption, (5) heat dissipation, (6) quick and simple installation, (7) at-a-glancemonitoring of system operation, (8) convenient, low-cost maintenance, and (9)high reliability.

Data Communications Transmitting and receiving coded digital signals between computers or otherdigital devices or systems according to agreed upon specifications or standards.

Data CommunicationsEquipment (DCE)

Equipment that provides the signal conversion, connection control, and codingrequired for communication between data terminal equipment and data circuits;may be independent (e.g., a modem) or an integral part of a computer.

DATALOOP® General DataComm's version of Digital Loopback test.

Data Set A modem; term infrequently used except within the telephone carrier industry.

F-3

Data TerminalEquipment (DTE)

Generally end-user devices, such as terminals and computers that connect toDCE, which either generate or receive the data carried by the network; in ITU-TV.24/V.28 connections, designation as either DTE or DCE determines signalingrole in handshaking; in a ITU-T X.25 interface, the device or equipment thatmanages the interface at the user premises.

Data Terminal Ready(DTR)

A signal from the terminal to the modem indicating that the terminal is ready toreceive and transmit.

dB Decibel; a unit of measurement used to express the ratio of two values, usually thepower of electrical or electromagnetic signals; equal to 10 times the logarithm de-rived from a ratio of the two power levels, which are expressed in watts; the rela-tive gain or loss of a signal when the measured signal value is compared in a ra-tio to another, usually its input, value.

dBm Decibel reference to one milliwatt; relative strength of a signal, calculated indecibels, when the signal is compared in a ratio to a value of one milliwatt; usedmainly in telephony to refer to relative strength of a signal (e.g., at 0 dBm, a sig-nal delivers 1 milliwatt to a line load, while at -30 dBm a signal delivers 0.001milliwatts to a load).

Diagnostics Tests used to detect malfunctions in a system or component.

Digital Techniques and equipment in which information is encoded as either a binary“1” or “0”; the representation of information in discrete binary form, discontinu-ous in time, as opposed to the analog representation of information in variable,but continuous.

Digital Loopback(DL)

Technique for testing the digital processing circuitry of a communications de-vice; may be initiated locally or remotely via a telecommunications circuit; de-vice being tested will echo back a received test message, after first decoding andthen reencoding it, the results of which are compared with the original message.

DTE Data Terminal Equipment.

Duplex Transmission Simultaneous two-way independent transmission in both directions. Also calledfull duplex transmission.

Equalization The process of reducing the effect(s) of amplitude frequency and/or phase distor-tion of a circuit by the introduction of networks to compensate for the difference inattenuation and/or time delay at the various frequencies in the transmissionbands.

External Modem A standalone modem, as opposed to a modem integrated within a computer orterminal.

Four-Wire Circuit Provision of two-wire pairs (or logical equivalent) for simultaneous two-waytransmission.

Ground An electrical connection or common conductor that, at some point, connects to theearth.

Half Duplex (HDX) Operational mode of a communications line where transmission occurs in eitherdirection, but not both directions simultaneously; transmission directions are al-ternately switched to accommodate two-way data flow.

F-2

InterfaceA shared boundary; a physical point of demarcation between two devices, wherethe electrical signals, connectors, timing, and handshaking are defined; the pro-cedure, codes, and protocols that enable two entities to interact for the meaningfulexchange of information.

ISDN Integrated Service Digital Network. Provides a wide range of voice and non-voiceservices within the same network.

LED Light-emitting diode.

Link The combination of communications devices, media and software intelligencethat is required to effect data communications.

Local Area Network A type of high-speed data communications arrangement wherein all segments ofthe transmission medium (typically, coaxial cable, twisted-pair wire, or opticalfiber) are under the control of the network operator.

Loopback Diagnostic procedure used for transmission devices; a test message is sent to adevice being tested, which is then sent back to the originator and compared withthe original transmission; loopback testing may be within a locally attached de-vice or conducted remotely over a communications circuit..

LTU Line Terminating Unit. The equipment that terminates the access line at thenetwork end.

Modem Modulator/demodulator; electronic device that enables digital data to be sent over(typically) analog transmission facilities.

M R Modem Ready.

Multipoint Line A single communications channel (typically a leased telephone circuit) to whichmore than one station or logical unit are attached, though only one may transmitat a time; such arrangements usually require some kind of polling mechanism,under the control of a master station, to ensure that only one device transmitsdata at a time; also, a multi-drop line.

Network An interconnected group of nodes; a series of points, nodes, or stations connectedby communications channels; the assembly of equipment through which connec-tions are made between data stations.

Node A point where one or more functional units interconnect transmission lines(ISO); a physical device that allows for the transmission of data within a network;an end-point of a link or a junction common to two or more links in a network(IBM SNA); typically includes host processors, communications controllers, clus-ter controllers, and terminals.

Noise Any extraneous and unwanted signal disturbances in a communications link(e.g., electromagnetic interference; random variations in signal voltage or cur-rent or interfering signals.

NTU Network Terminating Unit. The equipment that terminates the access line at thecustomer end.

Point to Point A circuit that connects two points directly, with generally no intermediate pro-cessing nodes or computers, although there could be switching facilities; a type ofconnection, such as a phone-line circuit, that links two, and only two, logical enti-ties.

F-5

Private Line A leased line, an unswitched circuit.

RD Receive Data.

RL Remote Loopback.

RemoteLoopback (RL)

Similar to the Digital Loopback diagnostic test, except no modem operator is re-quired at the looping modem. With RDL, a signal is sent down the communica-tions line which instructs the remote modem to place itself in digital loopbackmode.

Request To Send A signal to the sending modem that the terminal is ready to transmit; part of mo-dem handshaking.

RTS Request To Send.

RTS-CTS Delay The delay between the time that the data terminal equipment asserts Request toSend (RTS) and the time that the modem asserts Clear to Send (CTS). Sets thetime delay or turnaround time from reception to transmission.

SD Send Data.

Self-Test A diagnostic test mode in which the modem is disconnected from the telephone fa-cility and its transmitter’s output is connected to its receiver’s input to permit thelooping of test messages (originated by the modem test circuitry) through the mo-dem to check its performance.

Send Data (SD) Send data from DTE to DCE.

Switched Network Communications link for which the physical path, established by dialing, mayvary with each use (e.g., a dial-up telephone circuit).

SynchronousTransmission

Data communications in which characters or bits are sent at a fixed rate, with thetransmitting and receiving devices synchronized, eliminating the need for startand stop bits necessary in asynchronous transmission and significantly increas-ing data throughput rates.

TerminalA point in a network at which data can either enter or leave; a device, usuallyequipped with a keyboard, often with a display, capable of sending and receivingdata over a communications link (IBM); generically the same as data terminalequipment (DTE).

Test Generator Allows the operator to select a 511 test pattern generator.

Transmission The dispatching of a signal, message, or other form of intelligence by wire, radio,telegraphy, telephony, facsimile, or other means (ISO); a series of characters,messages or blocks, including control information and user data; the signalingof data over communications channels.

Transparent Mode Transmission of binary data with recognition of most control characters sup-pressed. In binary synchronous communications, entry to and exit from thetransparent mode are indicated by a sequence beginning with a special character.

Two-Wire Circuit Usually a telephone circuit consisting of two insulated electrical conductors, typi-cal of most local loops.

F-2

datacomm 610/612 network terminating unit - gdc · datacomm 610/612 network terminating unit...

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