General DataComm TMS-3000 User manual

Publication No. 036R480-000
Issue 6, January 1995
OPERATING AND INSTALLATION INSTRUCTIONS
FOR
TMS-3000
CELP VOICE CHANNEL
MODULE
General DataComm, Inc.
MIDDLEBURY, CONNECTICUT
06762-1299

ATTENTION!
STATIC SENSITIVE DEVICES
PROPER HANDLING AND GROUNDING
PRECAUTIONS REQUIRED
This equipment contains electrostatic sensitive devices. Use ESD precautionary
procedures when removing or inserting parts or printed circuit (pc) cards. Keep parts
and pc cards in their antistatic packaging material until ready to install.
The use of an antistatic wrist strap, connected to the grounded equipment frame or
chassis, is recommended when handling pc cards during installation, removal, or
setting of on-board option switches. Do not use a conductive tool, such as a screwdriver
or paper clip, to set the position 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
designed for wet locations.
c. Never touch uninsulated telephone wires or terminals unless the telephone line has
been disconnected at the network interface.
d. Use caution when installing or modifying telephone lines.
CAUTION
Potentially hazardous voltages exist within this unit.

TMS-3000
CELP VOICE CHANNEL
MODULE
(GDC PART NOs. 036M285-001 through -005)
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 A
digital device , pursuant to Part 15 of the FCC rules. These limits are designed to
provide reasonable protection against harmful interference when the equipment is
operated in a commercial environment. This equipment generates, uses and can
radiate radio frequency energy and, if not installed and used in accordance with
the instruction manual, may cause harmful interference to radio communica-
tions. Operation of this equipment in a residential area is likely to cause harmful
interference, in which case the user will be required to correct the interference at
his own expense.
The user is cautioned that any changes or modifications not expressly approved
by the party responsible for compliance would void the user's authority to operate
the equipment.
CRC-REQUIRED NOTIFICATION
This equipment is a Class A digital apparatus which complies with the Radio
Interference 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 to time in the content thereof. GDC assumes no liability for losses incurred
as a result of out-of-date or incorrect information contained in this manual.
The features described herein may not exist on all versions of the software and
are subject to change without notice.
READER’S COMMENTS
Comments regarding this manual should be addressed to:
Publications Department
General DataComm, Inc.
1579 Straits Turnpike
P.O Box 1299
Middlebury, CT 06762-1299
PROPRIETARY NOTICE
This publication contains information proprietary and confidential to General
DataComm, Inc. Any reproduction, disclosure, or use of this publication is
expressly prohibited except as General DataComm, Inc., may otherwise authorize
in writing.
Copyright, General DataComm, Inc., 1995

FCC-REQUIRED NOTIFICATION
FOR USERS OF FCC-REGISTERED EQUIPMENT
Read before using this technical manual or installing subject equipment.
This equipment complies with Part 68 of the Federal Communications Commission (FCC) Rules and
Regulations. Connection of data communication equipment to the public telephone network is
regulated by the FCC Rules and Regulations. These regulations require:
A. All connections to the telephone network must be made through standard plugs and telephone
company provided jacks or equivalent.
B. Connection of this equipment to party lines and coin telephones is prohibited.
C. If the telephone company asks you what equipment is connected to the telephone line, tell them to
which line the equipment is connected, and give them the FCC Registration number and Ringer
Equivalence number of the equipment. These numbers can be found on a label located on the back
of the front panel on all DataComm-type equipment and on the underside or rear panel of other
equipment.
D. If you experience trouble, disconnect the equipment from the telephone line to determine if the
equipment is malfunctioning. If it is, remain disconnected until the problem is corrected. Should
this equipment cause harm to the telephone network, the telephone company may discontinue your
service temporarily. If possible they will notify you in advance. But if advance notice is not
practical, you will be notified as soon as possible. You will be informed of your right to file a
complaint with the FCC.
E. The telephone company may change its communication facilities, equipment, operations, and
procedures where reasonably required for operation. If this occurs, the telephone company will
notify you in writing.
F. It is the user's obligation to notify the telephone company prior to disconnecting equipment from
1.544 Mbps digital service.
G. According to Part 68 of the FCC Rules and Regulations, customers are not authorized to repair or
modify this equipment. Any repair or modification will null and void the FCC registration and
the warranty of this equipment.
Rev. 4, October 1986

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 certification
means that the equipment meets certain telecommunications network protective, operational, and
safety requirements. 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 of the local telecommunications company. The equipment must also be installed using an
acceptable method of connection. In some cases, the company's inside wiring associated with a single
line individual service may be extended by means of a certified connector assembly (telephone
extension cord). The customer should be aware that compliance with the above conditions may not
prevent degradation of service in some situations.
Repairs to certified equipment should be made by an authorized Canadian maintenance facility
designated by 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
precaution may be particularly important in rural areas.
Caution: Users should not attempt to make such connections themselves, but should contact the
appropriate electric inspection authority, or electrician, as appropriate.
CANADIAN EMISSIONS REQUIREMENTS
“This digital apparatus does not exceed the (ClassA) limits for radio noise emissions from
digital apparatus set out in the Radio Interference Regulations of the Canadian Department of
Communications.”

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i
TABLE OF CONTENTS
Section &
Subject Page
1 — INTRODUCTION
OVERVIEW ................................................................................................................................................. 1-1
FUNCTIONAL DESCRIPTION ..................................................................................................................1-1
FUNCTION OF THE TMS/SUPERVISORY CONTROLLER.................................................................... 1-2
TECHNICAL MANUALS............................................................................................................................1-2
EQUIPMENT LIST......................................................................................................................................1-3
SERVICE AND TRAINING ........................................................................................................................ 1-3
APPLICATIONS.......................................................................................................................................... 1-3
2 — INSTALLATION
UNPACKING AND HANDLING................................................................................................................2-1
INSTALLATION PROCEDURES................................................................................................................ 2-1
PREOPERATIONAL CHECK .....................................................................................................................2-1
OPTION SELECTION .................................................................................................................................2-1
MOUNTING OF CELP VOICE CHANNEL MODULE...............................................................................2-4
CELP VOICE CHANNEL SIGNALING .....................................................................................................2-5
E-Lead Signaling State ..............................................................................................................................2-6
E-Lead Polarity.......................................................................................................................................... 2-6
Noise Suppression Filter ...........................................................................................................................2-7
In-Band E&M Signaling ..........................................................................................................................2-7
E-Lead Loss of Sync...................................................................................................................................2-8
CELP Module Analog Levels .................................................................................................................... 2-9
Analog Input Fine Level Adjustments...................................................................................................... 2-10
Echo Canceller ........................................................................................................................................... 2-11
3 — OPERATION
OVERVIEW ................................................................................................................................................. 3-1
CONTROLS, INDICATORS AND CONNECTORS....................................................................................3-1
4 — PRINCIPLES OF OPERATION
OVERVIEW ................................................................................................................................................. 4-1
Base Card Operation .................................................................................................................................. 4-1
E&M Signaling (-001 Version) ................................................................................................................. 4-1
E&M Signaling (-002, -003, -004, -005 Versions) ....................................................................................... 4-2
Piggyback Card Operation ........................................................................................................................4-2
5 — TESTS
OVERVIEW ................................................................................................................................................. 5-1

ii
TABLE OF CONTENTS (Cont.)
Section &
Subject Page
5 — TESTS (Cont.)
DATA PATH TESTS................................................................................................................................... 5-1
Digital Test................................................................................................................................................5-1
Control State Test....................................................................................................................................... 5-1
User Data Test ........................................................................................................................................... 5-1
1 kHz Tone Test ........................................................................................................................................ 5-1
SET dB LEVEL ADJUSTMENT.................................................................................................................. 5-2
TEST POINTS.............................................................................................................................................5-2
TECHNICAL ASSISTANCE PROCEDURE................................................................................................ 5-2
TRAINING ..................................................................................................................................................5-3
APPENDIX A — TECHNICAL CHARACTERISTICS
APPENDIX B — CELP VOICE CHANNEL MODULE APPLICATIONS
APPENDIX C — M-LEAD SIGNALING INTERFACES
APPENDIX D — CELP CIRCUIT VOICE LEVEL TESTING
APPENDIX E — CELP VOICE CHANNEL MODULE CONNECTOR PIN ASSIGNMENTS
APPENDIX F — GLOSSARY
INDEX
LIST OF ILLUSTRATIONS
Section &
Figure Page
2 — INSTALLATION
2-1 CELP VOICE CHANNEL MODULE OPTION LOCATIONS...........................................................2-3
3 — OPERATION
3-1 CELP VOICE CHANNEL MODULE FRONT PANEL ................................................................... 3-2
LIST OF TABLES
Section &
Tables Page
1 — INTRODUCTION
1-1 EQUIPMENT LIST........................................................................................................................... 1-3
1-2 FEATURE LIST ................................................................................................................................1-3

iii
LIST OF TABLES (Cont.)
Section &
Tables Page
2 — INSTALLATION
2-1 CELP PLUG-IN OPTION, SIGNALING TYPE............................................................................... 2-2
2-2 VOICE CHANNEL CONNECTION CABLES ..................................................................................2-4
2-3 OPTION SELECTIONS, M-SIGNALING TYPES.............................................................................2-5
2-4 OPTION SELECTIONS, E-LEAD SIGNALING STATE..................................................................2-6
2-5 OPTION SELECTIONS, E-LEAD POLARITY ................................................................................ 2-6
2-6 OPTION SELECTIONS, NOISE SUPPRESSION FILTER ..............................................................2-7
2-7 OPTION SELECTIONS, IN-BAND E&M SIGNALING...................................................................2-7
2-8 OPTION SELECTION, E-LEAD CONDITION UPON LOSS OF SYNC......................................... 2-8
2-9 OPTION SELECTION, INPUT/OUTPUT LEVELS.........................................................................2-9
2-10 OPTION SELECTIONS, INPUT LEVEL ADJUSTMENT...............................................................2-10
2-11 OPTION SELECTIONS, CODEC TIMING......................................................................................2-11

SECTION 1
INTRODUCTION
OVERVIEW The CELP (Codebook Excited Linear Predictive) Voice Channel Module
is an analog voice channel card for the TMS-3000, TMS Compact, Univ.
MM+ V4 TDM and the MINIMUX TDM. The CELP module provides
voice encoding algorithms that maximize voice channel bandwidth
utilization while offering low bit rate values of 4.8 and 6.4 kHz. A CELP
module in a TMS-3000 also offers a bit rate of 9.6 kHz. OCM CELP is
covered in GDC Publication 036R340-000.
The CELP Voice Channel Module is used in transmission applications to
maximize available bandwidth. Applications include use in digital ser-
vices such as ASDS (FT-1), ADN, satellite and in feeder applications in
which a customer needs to integrate both voice and data. Voice communi-
cation is two-way simultaneous (full duplex).
FUNCTIONAL
DESCRIPTION The CELP Voice Channel Module consists of two cards; a base card and a piggyback card. Voice is first processed by an analog-to-digital conver-
sion on the base card yielding a 64 kHz data rate. This data is then con-
verted to a low bit channel rate through software on the piggyback card.
The bit rate is 4.8, 6.4 or 9.6 kHz. An echo canceller feature is provided
for large inherent delays involved in the digital signal processing of the
voice channel.
2-state in-band E&M signaling is supported. Overhead bandwidth is not
required through the multiplexer network for signaling.
The CELP Voice Channel Module mounts into the TMS-3000 or TMS
Compact channel or expansion shelf. In the Univ. MM+ V4 TDM or
MINIMUX TDM it mounts into the channel slot.
The CELP Voice Channel Module utilizes a 600 ohm 4-wire interface with
E&M signaling and connects to the voice terminating equipment via a
GDC standard voice channel connection cable.
The CELP Voice Channel Module (-002) supports Group 3 FAX transfers at
the 6.4 kHz voice multiplexer data rate with in-band E&M signalling.
The CELP Voice Channel Module (-003) supports 4.8 kHz voice only with
in-band E&M signalling.
The CELP Voice Channel Module (-004) supports voice and Group 3 FAX
transfers at the 6.4 KHz voice multiplexer data rate with In-band E&M
signaling. When operating in a TMS-3000, 9.6 kHz is also available.
The CELP Voice Channel Module (-005) supports 4.8 kHz voice only with
in-band E&M signalling. When operating in a TMS-3000, 9.6 kHz is also
available.
1-1

INTRODUCTION
FUNCTION OF
THE TMS/
SUPERVISORY
CONTROLLER
NOTE
In the TMS-3000 and TMS Compact, the Controller is
referred to as the TMS-3000 Controller, TMS Controller or
Controller. In the Univ. MM+ V4 TDM and MINIMUX
TDM, the Controller is referred to as the Supervisory Con-
troller.
In this manual, the abbreviation TMS/Supervisory Controller will be
used.
The TMS/Supervisory Controller performs the following functions:
•Recognize the type of voice card
•Configure the voice card
• Program the voice card hardware according to line speed, etc.
•Monitor and report status and alarms, and
•Support diagnostic procedures involving the voice card.
TECHNICAL
MANUALS To assist in installation of the CELP Voice Channel Module, it is rec- ommended that the following manuals be available:
If installing in a TMS-3000:
•Operating and Installation Instructions Manual for TMS-3000, GDC
Publication No. 036R303-000 and TMS-3000 User's Guide for Software
Version GTS 2.0 (or later), GDC Publication No. 036R603.
Installing in a TMS Compact:
•Instruction Manual for TMS Compact, GDC Publication No. 036R320-
000 and TMS-3000 User's Guide for Software Version GTS 2.0 (or
later), GDC Publication No. 036R603.
Installing in a Univ. MM+ V4 TDM:
•Instruction Manual for the MEGAMUX PLUS TDM, GDC Publication
No. 036R360-000 and the Operator's Instructions for the MEGAMUX
PLUS TDM, GDC Publication No. 036R660-000.
Installing in a MINIMUX TDM:
•Instruction Manual for the MINIMUX TDM, GDC Publication No.
036R333-000.
1-2

INTRODUCTION
EQUIPMENT LIST The components that make up the CELP Voice Channel Module are pre-
sented in Table 1-1. Available features are shown in Table 2-2. The part
numbers in the list generally represent assemblies made of several
discrete parts. Technical Characteristics of the CELP Voice Channel
Module are given in Appendix A.
SERVICE AND
TRAINING See Section 5, TESTS, for information on service and training available from GDC.
APPLICATIONS Appendix B contains typical applications of the CELP Voice Channel
Module.
TABLE 1-1. EQUIPMENT LIST
Equipment Supplied Designation GDC Part No.
CELP Voice Channel Module
CELP Plug-in — 036P285-001, -002, -003, -005
CELP Basecard — 036P286-001
TABLE 1-2. FEATURE LIST
Voice Module Equipment Features
036M285-001 (CELP 1) 036P285-001
036P286-001 Voice at 6.4/4.8 kHz E&M signalling – out of band
036M285-002 (CELP/FAX) 036P285-002
036P286-001 Voice at 6.4/4.8 kHz E&M signalling – in-band/out-of-band
FAX Group 3 at 6400 bps rate
036M285-003 (CELP 2) 036P285-003
036P286-001 Voice at 4.8 kHz E&M signalling in-band/out-of-band
036M285-004 CELP 96/FAX 036P285-005
036P286-001 Voice at 9.6/6.4/4.8 KHz E&M
signaling in-band and out-of-band FAX
Group 3 at 9.6/6.4 KHz rates
036M285-005 CELP 96 036P285-005
036P286-001 Voice at 9.6/4.8 KHz E&M signaling in-
band and out-of-band
NOTE
9.6 kHz is available only in TMS-3000.
1-3

SECTION 2
INSTALLATION
UNPACKING AND
HANDLING Inspect the CELP Voice Channel Module for damage; if any is found, no-
tify the shipper immediately. Do not discard the box and packing mate-
rial; their use will facilitate reshipping the unit, if necessary.
INSTALLATION
PROCEDURES In the TMS-3000 or TMS Compact, the CELP Voice Channel Module mounts into the channel or expansion shelf. In the Univ. MM+ V4 or
MINIMUX TDM, the CELP Voice Channel Module mounts into a channel
slot. The shelf should be located in a ventilated area where the ambient
temperature does not exceed 124°F (50°C). Do not install the unit directly
above equipment that generates a large amount of heat (such as power
supplies). Table 2-2 lists the various cables required for specific CELP
applications.
PREOPERATIONAL
CHECK In many instances, a CELP Voice Channel Module may seem to be inop- erative in a particular system, when actually the pc board jumper posi-
tions or software options have been improperly selected or a fault exists
elsewhere in the system.
The CELP Voice Channel Module supports several diagnostic tests that
can be performed through the TMS/Supervisory controller. Section 5 de-
scribes these tests.
If the CELP Voice Channel Module passes these tests, but subsequently
fails to perform voice communications, the CELP may not be at fault. An
error may have been made in the installation or configuration, or there
is a faulty communication line or faulty remote installation. Recheck the
cables, line connections, the option strapping, and soft option selection.
In the event that the CELP Voice Channel Module does not check out
properly, replace it with a spare CELP Module, if available. Do not
attempt to repair the CELP Module. For assistance, contact DataComm
Service Corporation (see Section 5).
OPTION
SELECTION The CELP Module contains both hardware and software optioning. This manual deals mainly with the hardware configuration of the CELP
Module. To configure software options on a CELP Voice Channel Module
installed in the TMS-3000 or TMS Compact, refer to the TMS-3000 User's
Guide for Software Version GTS 2.0 (or later), GDC Publication No.
036R603.
To configure software options on the Univ. MM+ V4 TDM, refer to the
Operator's Instructions for the Univ. MM+ V4 TDM, GDC Publication No.
036R660-000.
To configure software options on the MINIMUX TDM, refer to the Instruc-
tion Manual for the MINIMUX TDM, GDC Publication No. 036R333-000.
2-1

INSTALLATION
There is one hardware option on the piggyback card. That option is
described in Table 2-1.
TABLE 2-1. CELP PLUG-IN OPTION, SIGNALING TYPE
Feature Jumper X1 Application
E&M Signaling E&M Normal jumper position
AC15 Signaling AC15 Future use jumper position
Note that switch SW1 on the piggyback card has been adjusted at the
factory. Do not under any circumstances change the settings of SW1 on
the piggyback card.
Figure 2-1 shows the location of the option switches and jumpers on the
CELP base card.
Tables 2-3 through 2-10 provide the information necessary to configure the
CELP Voice Channel Module for the TMS-3000.
2-2

INSTALLATION
UK
S1
ON 1 2 3 4 5 6 7 8
S2
FL1 FL2 FL3
TP3
TP2
TP1
UK
US
UK
DS3
DS4
X3 X2
X1 X4 X5 X6 X7 X8 X9
INT
GND
GND
BAT
GND
BAT
M MUS IDL
BSY
+
-+PIGGYBACK P/N 036P285
CELP PIGGYBACK CARD
036P286-001
NOTE
JUMPERS SHOWN IN DEFAULT POSITION.
DS1
DS2
J1
INT
M
IDL
BSY -
US
DEFAULT FOR S1-1 THROUGH S1-8 IS OFF. THIS
PROVIDES O dBm TRANSMIT AND O dBm RECEIVE
LEVELS. DEFAULT FOR S2-1 THROUGH S2-4 IS OFF.
DEFAULT FOR S2-5 IS ON S2-6 THROUGH S2-8 IS OFF.
TYPE I SIGNALING REQUIRED TO INTERFACE
TO TELLABS SATE MODULES. JUMPER X5
AND X6 SHOULD BE SET TO IDL FOR PLAR
CIRCUITS.
XA1J1
XA1J2
NOTE
X11
CSIG
NORM
FIGURE 2-1. CELP OPTION LOCATIONS
2-3

INSTALLATION
MOUNTING OF
CELP VOICE
CHANNEL
MODULE
The CELP Voice Channel Module consists of two subassemblies, the
CELP base card and piggyback card. The CELP base card is a standard
GDC channel card 9 in. x 6.25 in. (22.86 cm x 15.88 cm) with edge finger
connections to the harness card on the opposite side to the front panel.
The CELP Voice Channel Module piggyback card is 6 in. x 4.6 in. (15.24
cm x 11.43 cm). It mounts onto the base card with the component side fac-
ing down via two sockets. Standoffs provide 0.5-inch (1.27-cm) spacing be-
tween the cards.
The CELP Voice Channel Module mounts into an empty channel slot in
the TMS-3000, TMS Compact, Univ. MM+ V4 or MINIMUX TDM.
Connections to the 4-wire VF line are made via standard GDC voice
channel cables (refer to Table 2-2).
TABLE 2-2. VOICE CHANNEL CONNECTION CABLES
GDC Cable No. Description Application
027H306 Voice Channel, DB-25 connector to spade
lugs Single channel connection; tip, ring, E-lead, M-lead, and ground brought out to spade lugs. Available in 5-,15-, and
25-foot lengths.
027H409 Voice Channel, DB-25 connector to punch-
down wire leads Single channel connection; tip, ring, E-Lead, M-Lead, sta- tion battery, signal and station ground brought out to wire
ends for punch-down applications. Available in 5-, 15-,
and 25- foot lengths.
326H024 TMS-3000, TMS Compact, MM PLUS or
MINIMUX TDM to PBX;
DB-25 connector to 50-pin Amphenol
connector. Up to 8 voice channels.
Used to connect up to 8 voice channels to private branch
exchange. 5-foot length only; requires 021H605-025 ex-
tension cable.
326H025 8-channel harness; DB-25 connector to
50-pin Amphenol connector Used to connect up to 8 voice channels to facility. Transmit and receive leads crossed over. 5-foot only.
Requires 021H605-025 extension cable.
326H026 6-channel harness; DB-25 connector to
50-pin Amphenol connector Used to connect up to 6 voice channels to facility.
021H623 TMS-3000, TMS Compact, MM PLUS or
MINIMUX TDM to Tellabs 266D shelf (6
voice channels)
Used to connect up to 6 voice channels to Tellabs 266AR
shelf. Available in 5- or 15-foot lengths.
021H622 TMS-3000, TMS Compact, MM PLUS or
MINIMUX TDM to Tellabs 266XR-12 shelf
(12 voice channels)
Used to connect up to 12 channels to Tellabs 266AR
shelf. Available in 5- or 15-foot lengths.
830-002S008 50-pin Amphenol male to male extension
cable (25 pairs) Used to connect 50-pin cables above to customer voice termination point (demark), (voice channel to PBX).
830-002S007 50-pin Amphenol male to female
extension cable (25 pairs) Used to connect Tellabs shelf to customer voice termina- tion point (demark) (Tellabs Shelf to PBX).
2-4