AT&T MERLIN LEGEND Release 2.0 Analog Multiline... User manual

555-610-131
Issue 1
August 1991
MERLIN LEGEND 
Communications System
Release 2.0
Data User’s Guide

Copyright
All Rights
Printed in
Notice
© 1992 AT&T AT&T 555-620-129
Reserved
Issue 1
U.S.A. October 1992
Every effort was made to ensure that the information in this book was
complete and accurate at the time of printing. However, information is
subject to change.
Federal Communications Commission (FCC)
Electromagnetic Interference Information
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
communications. 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.
Canadian Department of Communications (DOC)
Interference Information
This digital apparatus does not exceed the Class A limits for radio noise
emissions set out in the radio interference regulations of the Canadian
Department of Communications.
Le Present Appareil Numerique n’emet pas de bruits radioelectrlques
depassant Ies Iimites applicable aux appareils numeriques de la class A
prescribes clans Ie Reglement sur Ie brouillage radioelectrlque edicte par
Ie ministere des Communications du Canada.
Trademarks
MERLIN LEGEND is a trademark of AT&T in the U.S. and other countries.
ACCUNET is a registered trademark of AT&T.
Hayes is a registered trademark of Hayes Microcomputer Products, Inc.

Contents
About This Guide 1
■ Conventions 2
■ How to Comment on This Guide
3
1
About Data Communication
Equipment
Terminology
Data Stations
Modem Pools
Data Hunt Groups
Communications Software Setup
Synchronous Mode vs. Asynchronous
Mode
1-1
1-2
1-4
1-12
1-15
1-17
1-19
2
Feature Finder
2-1
Table of Contents i

Contents
3
Making and Answering Data
Calls
3-1
■ Making Analog Data Calls
3-3
■ Making Digital Data Calls
3-14
■ Making Data Calls Through a Modem Pool
3-22
4 Features
4-1
■ Account Code Entry
4-3
■ Auto Answer All
4-5
■ Data Status 4-7
■ Personal Speed Dial 4-9
■ Privacy
4-11
■ System Speed Dial 4-13
A
ii
Call Progress Messages
Table of Contents
A-1

The exclamation point in an
equilateral triangle is intended to
alert the user to the presence of
important operating and
maintenance (servicing)
instructions in the literature
accompanying the product.
IMPORTANT SAFETY INSTRUCTIONS
Always follow these basic safety precautions when using your
telephone equipment. These precautions reduce the risk of
fire, electrical shock, and injury to you and damage to the
equipment.
Read and understand all instructions.
Follow all warnings and instructions marked on or
packed with the telephone.
Do not use the telephone near water, as in a wet
basement. The telephone can be hazardous if
immersed in water. To avoid the possibility of
electrical shock, do not use it when you are wet. If you
accidentally drop it into water, do not retrieve it until
you have first unplugged the line cord from the
modular wall jack. Do not plug the telephone back in
until it has dried thoroughly.
iii

Do not use the telephone during electrical storms in
your immediate area. There is a remote risk of
electrical shock from lightning.
Unplug the telephone from the wall outlet before
cleaning. Use a damp cloth for cleaning. Do not use
liquid or aerosol cleaners on the telephone.
Never push objects of any kind into the telephone
through openings or slots. Never spill liquid of any
kind on the telephone.
Do not use the telephone near a gas leak. If you
suspect a gas leak, report it immediately, but use a
telephone away from the area in question. The
telephone’s electrical contacts could generate a tiny
spark. While unlikely, it is possible that the spark could
ignite heavy concentrations of gas.
To reduce the risk of electrical shock, do not
disassemble the telephone. There are no user-
serviceable parts inside. Opening or removing covers
may expose you to hazardous voltages, and incorrect
reassembly can cause electrical shock when the
telephone is used.
Call your sales representative or authorized dealer
when service or repair work is needed.
Auxiliary equipment includes answering machines,
alerts, modems, and fax machines. To connect one of
these devices, you must first have a Multi-Function
Module (MFM).
iv

WARNING:
For your personal safety, DO NOT install an
MFM yourself.
ONLY an authorized technician or dealer
representative shall install, set options, or
repair an MFM.
To eliminate the risk of personal injury due to
electrical shock, DO NOT attempt to install or
remove an MFM from your MLX telephone.
Opening or removing the module cover of
your telephone may expose you to dangerous
voltages.
SAVE THESE INSTRUCTIONS
v

About This Guide
This book describes the data stations supported by the
system and how to make and receive data calls on these
stations when using the MERLIN LEGEND™ Communications
System. This guide does not provide instructions for setting
up your data station or loading and running your
communications software. Refer to the appropriate
documentation with your communications software and
equipment for these instructions.
About This Guide 1

About This Guide
Conventions
2
The following typographical conventions are used in this
book:
Bold type is used for telephone buttons.
Press SA Ring to select an SA button.
The Carriage Return key
However, your keyboard
[RETURN ] .
may show
is represented by [↵↵ ] .
[ENTER ] or
Italic type is used for emphasis and as a substitute for
information for which you must supply a specific value.
Dial dial-out code.
Constant width type is used for information on
telephone display screens or on a PC screen.
Connected
Call Status: Idle
Bold constant width type indicates information
that you enter exactly as shown.
Type #; dial #82.
Conventions

About This Guide
How to Comment on This
Guide
We welcome your feedback on this book. Please use the
feedback form on the next page. If the form is missing, send
your comments to A. Sherwood, AT&T, 99 Jefferson Road,
Rm. # 2A25, Parsippany, NJ 07054.
How to Comment on This Guide 3

About Data
Communication
Equipment
This chapter provides an overview of the features and
equipment used for data communications with the telephone
communications system. It describes the following:
■ data stations
■
modem pools
■ data hunt groups
■
communications software setup
■
synchronous mode vs. asynchronous mode
For information on setting up your data station and loading
and running your communications software, refer to your
equipment or communications software documentation or
contact your system manager. Your system manager is
About Data Communication Equipment 1-1

About Data Communication Equipment
responsible for administering and managing your
communications system.
Terminology
General terms used in describing data transfer in this guide
are defined as follows.
asynchronous data transmission — A method of transmitting
a short bit stream of data, such as printable characters
represented by a 7- or 8-bit ASCII code. Each string of data
bits is preceded by a start bit and followed by a stop bit, thus
permitting data to be transmitted at irregular intervals.
control unit — The housing, carriers, power supply module,
processor module, and line/trunk and station modules of a
communications system.
conversion resource (or modem pool) — A pair, or group of
pairs, of modems and data modules with interconnected RS-
232 interfaces that converts digital signals to analog, or
analog signals to digital, thereby allowing users with digital
data stations to communicate with users who have analog
data stations and vice versa.
data hunt group (DHG) — A group of analog or digital data
stations that share a common access code. Calls are
connected in a round-robin fashion to the first available data
station in the group.
1-2
Terminology

About Data Communication Equipment
endpoint — The final destination in the path of an electrical or
telecommunications signal.
local area network (LAN) — A networking arrangement
designed for a limited geographical area.
MLX port — A digital point of access into a communications
system, computer, network, or electronic device.
tip/ring (T/R) — The contacts and associated conductors of a
single-line telephone plug or jack.
synchronous — A method of transmitting a continuous digital
data stream in which the transmission of each binary
synchronized with a master clock.
Terminology
1-3

About Data Communication Equipment
Data Stations
A data station is a combination of Data Terminal Equipment
(DTE), such as a computer terminal, personal computer (PC),
printer, optical scanner, or fax machine, and Data
Communications Equipment (DCE), such as a modem or data
module.
DTE connects to the communications system via the DCE
which has capabilities similar to a telephone. The DCE places
the data call, maintains its connection, and terminates the
data call.
NOTE:
Depending on your equipment, your DCE and DTE may
have options which can be set for transferring or receiving
data, such as parity and bit rate setting. Also, options
may be different depending on whether you are
transferring data synchronously or asynchronously. Be
sure to check your DTE or DCE documentation for a list of
available options and when and how these options can
be changed.
There are two types of data stations: analog and digital. Calls
between analog and digital data stations are possible only if
the communications system includes a conversion resource
called a modem pool which is described later in this chapter.
1-4
Data Stations

About Data Communication Equipment
Analog Data Stations
Analog data stations use modems to send and receive
information.
Modems convert outgoing digital signals from the data
terminal into analog signals for transmission, and convert
incoming analog signals to digital signals for the data
terminal. It may provide dialing and answering capabilities for
the data station, depending on modem features.
Except for an analog multiline telephone, a telephone
connected to a modem operates independently from the data
station. The modem handles the data call over the regular
telephone company network or with another data station
inside the system.
Data Stations 1-5

About Data Communication Equipment
The following analog data stations are supported:
Analog Voice and Analog Data. This endpoint
includes an analog multiline telephone and a data
terminal or PC connected to the system via a modem.
A General Purpose Adapter (GPA) supplies the tip/ring
(T/R) interface for the modem.
1-6 Data Stations

About Data Communication Equipment
Analog Data-only Station. This endpoint includes a
modem.
terminal connected to the control unit via a
The modem may accommodate a telephone;
however, the data station and telephone would not be
independent of each other (for example, the telephone
and data terminal cannot be used simultaneously.
Data Stations 1-7

About Data Communication Equipment
■
Digital Voice and Analog Data. This endpoint
connects via a modem to a T/R interface supplied by a
Multi-Function Module (MFM) in an MLX telephone
which, in turn, connects to the control unit. The
modem converts the digital signal to an analog signal
that is sent through the MFM (in the MLX telephone) to
the control unit. The voice communication capabilities
of the MLX telephone and data station are completely
independent of each other.
1-8
Data Stations

About Data Communication Equipment
Digital Data Stations
At a digital data station, you connect a data module to a DTE
to place and answer data calls at that station. A data module
transmits digital data to other digital data stations, including a
local host computer or local area network (LAN) workstation.
The communications system uses the 75006 Data Module to
connect to digital DTE. It connects on the system end
through an MLX port. It may share the MLX port with an MLX
telephone; however, the two units operate independently of
each other. The data module may also provide dialing and
answering capabilities to the data station.
The 7500B Data Module handles the data call over digital
telephone company facilities such as Primary Rate Interface
(PRI) or with another data station inside the system.
Data Stations 1-9

About Data Communication Equipment
The following digital data stations are supported.
Digital Voice and Digital Data. This endpoint
connects to the control unit via a 7500B Data Module.
The data module also has an attached MLX telephone.
The MLX port is shared by both the telephone and the
data station but they operate independently of each
other.
NOTE:
For a Digital Voice and Digital Data station, the
MLX telephone cannot contain a Multi-Function
Module (MFM). If you cannot communicate with
the switch, verify that the MLX telephone does not
contain an MFM.
1-10
Data Stations