AT&T Merlin II Feature Module 2 Use and care manual

AT&T
MERLIN
®
II
COMMUNICATIONS SYSTEM
Feature Module 2
Data Communications Guide

©1988 AT&T
All Rights Reserved
Printed in USA
Issue 2
May, 1988
NOTICE
The information in this document is subject to change without notice. AT&T assumes no responsibility
for any errors that may appear in this document.
MERLIN is a registered trademark of AT&T
To order copies of this document, call the AT&T Customer Information Center, 1-800-432-6600 and
include the document number 518-600-039 with your order.

Contents
Section 1: Introduction
What’s in This Guide
1-1
How to Use This Guide
1-2
Data Communications with the MERLIN II System
1-3
Section 2: Planning Data Options
Planning Overview
Components of the MERLIN II System
Identifying Line and Station Modules
Reserving Line Jacks
Reserving Station Jacks for Voice and Data Workstations
Reserving Jacks for Computer Access and Modem Pools
Planning Data Hunt Groups
Master Planning Form
Incoming Modem Pool Form
Data Hunt Group Form
2-1
2-3
2-5
2-8
2-9
2-14
2-20
2-21
2-25
2-27
Section 3: Connecting Hardware and Setting Options
Installation Overview
3-1
Simultaneous Voice and Data at Digital Stations
3-2
Digital Stations for Data Communications Only
3-6
Simultaneous Voice and Data at Analog Stations
3-7
Local Host Computer Access
3-9
Modem Pools
3-12
Section 4: Administering Data Options
Administration Overview
4-1
Basic Administration for Analog Station Jacks
4.3
Modem Pools
4-4
Data Hunt Groups
4-6
The Local Host Interface Feature
4-8
Data Status Buttons for Digital Voice Terminals
4-9
Simultaneous Voice and Data at Analog Voice Terminals 4-10
Section 5: Using Data Equipment for Calls
Overview
5-1
Data Calls with Digital Voice and Data Equipment
5-3
Data Calls with an Analog Voice Terminal
5-10
Data Calls to Digital Stations from Other Locations
5-12
Special Information for Placing Data Calls
5-13
Voice Calls Dialed from a Computer or Data Terminal
5-15
Index

What’s in This Guide
SECTION 1:
INTRODUCTION
SECTION 2: PLANNING
DATA OPTIONS
SECTION 3: CONNECTING
HARDWARE AND SETTING
OPTIONS
The information in this guide is divided into five sections, as described below.
This section tells what’s in the guide and how
to use it. It also gives an
overview of data communications with the MERLIN®II Communications
System. In addition, it defines basic terms.
This section helps system administrators make basic decisions about how to
use the data options that the MERLIN II system provides. It includes forms
for recording those decisions.
This section explains how to connect data hardware to the control unit and to
other equipment in the MERLIN II system. It also provides information on
setting option switches for data stands, data modules, and modems.
SECTION 4: This section shows administrators how to use the information on the planning
ADMINISTERING DATA forms to customize the system to meet specific data communications needs,
OPTIONS
SECTION 5: USING DATA
This section explains how to handle internal and outside data calls and how
EQUIPMENT FOR CALLS
to place voice calls from a computer or data terminal. It contains separate
instructions for people with digitaI and analog ‘voice terminals.
What’s in This Guide 1-1

How to Use This Guide
SETTlNG UP DATA
OPTIONS FOR THE FIRST
TIME?
MAKING CHANGES TO A
SYSTEM WITH DIGITAL
DATA CAPABILITY?
MAKING A DATA CALL
FOR THE FIRST TIME?
This guide to data options is intended as a supplement to the MERLIN II
System Manual
that you received with your system. How you should use the
guide at any particular time depends on what you want to do.
Use the information in Section 2, “Planning Data Options” to decide which
options you want for your system and complete the appropriate forms. If
your data equipment hasn’t been installed, follow the instructions in
Section 3, “Connecting Data Hardware and Setting Options.” (If you aren’t
experienced in hardware installation, have someone else perform this step.)
After the equipment is installed, perform the procedures in Section 4,
“Administering Data Options” that apply to your system.
Update your pl
anning forms to reflect the changes you want to make. Then
perform the appropriate procedure(s) in Section 4, “Administering Data
Options.” If the change requires changing hardware or hardware option
settings, see Section 3,
“Connecting Hardware and Setting Options.”
See the relevant entries in Section 5, “Using Data Equipment for Calls."
How to Use This Guide 1-2

Data Communications with the MERLIN II System
The MERLIN II system provides for simultaneous voice and data
communications using internal or outside telephone lines. A person with a
data terminal or personal computer can make a data call to a host computer,
for example, then place or receive voice calls without affecting the data
connection.
SYSTEM COMPONENTS
Figure 1-1 shows how data and voice equipment is connected in the
MERLIN II system. As this illustration shows, the system can accommodate
several different types of voice and data workstations. Two special features
of the MERLIN II system, data hunt groups for local host computer access
and modem pools, allow users to share the data communications equipment
needed for internal and outside data calls.
NOTE: Compatibility with the PC/PBX Connection and other data
products will be discussed in the documentation for those products.
Definitions of the terms used in Figure 1-1 and elsewhere in this guide are
found in “Definitions of Basic Terms. ”
Section 2 provides a detailed
description of the basic components of the MERLIN II system.
Data Communications with the MERLIN II System 1-3

FIGURE 1-1 Connectivity diagram for system components.
Two ports to Analog Voice Data
single 4 - pair Terminal
wiring point
Analog
station
module
General
Purpose
adapter
Modem
ANALOG
VOICE AND
DATA
Modem
pool #2
Basic
telephone
module
Digital
station
Outside Line
Outside Line
MPDM
MPDM
Host
computer
MPDM
7406 with
data stand Data
terminal
Data Hunt
Group
PT 510D
DIGITAL
VOICE
AND
DATA
Data
Terminal
PC/PBX Connection
DIGITAL
DATA
ONLY
Control Unit
1-4 Data Communications with the MERLIN II System

DEFINITIONS OF BASIC
Analog
TERMS
Basic Telephone
and Modem
Interface (BTMI)
Call Progress
Messages
Control Unit
Data
Communications
Equipment (DCE)
Data Hunt Group
Data Metering
Data Module
Data Rate or Speed
Data Stand
Data Terminal
Equipment (DTE)
Digital
Designed to transmit signals as continuous electrical
waves. Analog voice terminals such as the 10-button
and 34-button deluxe models can be directly connected
only to analog jacks at the control unit.
Connects basic telephones and data communications
devices, such as modems, to analog station jacks at
the MERLIN II control unit.
Messages sent to a computer or data terminal from the
control unit, data module, modem, or data stand.
These messages tell the user how calls are proceeding.
If a call can’t go through, an explanatory message
such as Incompatible Far End appears.
The master component in the MERLIN II system. It
manages all call traffic for the system and controls all
system responses.
A device used to transmit binary data to and/or from a
communication channel.
A group of digital station jacks that are assigned a
common access number. When a call is placed to a
data hunt group, the system checks the jacks in
round-robin fashion and connects the call to the first
one available.
A feature of a data stand that allows it to
communicate with another DCE or DTE (see Data
Terminal Equipment below) device at a rate lower
than the rate set for the terminal to which the data
stand is connected.
A general term used in this guide to refer to the
Modular Processor Data Module (MPDM) and the
Modular Trunk Data Module (MTDM).
The rate at which digital data signals are sent between
data communications equipment and/or data terminal
equipment. For example, the data rate of a modem
that transmits at 1200 bits per second (bps) is 1200.
A device that provides a DCE interface when
connected to a 7406 voice terminal for a data terminal
or personal computer.
A device used to convert character information to
and/or from binary data.
Designed to transmit signals as a sequence of separate
electrical pulses. Digital voice terminals such as the
7406 model and digital personal terminals such as the
PT51OO can be directly connected only to digital jacks
at the control unit.
Data Communications with the MERLIN II System 1-5

Digital Data Data communications equipment that receives and
Endpoint
transmits digital data signals to the control unit. The
7406 data stand, the Personal Terminal [PT) 51OD, the
MPDM, and the MTDM are digital data endpoints.
Line Jack
A jack that connects an outside line to the control
unit.
Local Host
A method of connecting digital station jacks to an on-
Computer Access
site computer for data only calls by MPDMs. Some or
all of these digital station jacks may be put in a data
hunt group.
Modem The equipment that comprises a member of a modem
Configuration pool. A modem configuration is made up of a
MTDM, a modem, and all required cables and cords.
If it is connected to an analog station jack, it also
includes a BTMI.
Modem Pool
A group of modems and associated equipment used to
convert digital data to analog data or vice versa.
Pooling makes it possible for users to share a limited
number of modems. Calls come into incoming
modem pools at the analog end of the modem
configuration; calls come into outgoing modem pools
at the digital end of the modem configuration.
Modular Processor A DCE device that converts digital data signals from
Data Module the control unit switching facilities to EIA RS-232-C
(MPDM) data
signals for a computer or data terminal and vice
versa. MPDMs are used with data terminals or
computers for data only at digital stations and for local
host computer access.
Modular Trunk
Data Module
(MTDM)
Outside Line
Station
Station Jack
A DTE device that serves as the interface between the
control unit and a modem. Together with a modem,
it changes digital data signals from the switching
facilities to analog signals that can be transmitted over
standard telephone lines or vice versa. MTDMs are
used in modem pools.
The telephone lines that come from your local
telephone company central office (CO) to your
building. These lines may be connected to your
MERLIN II control unit or to a modem for use in
modem pools on dedicated outside lines.
Any location in the MERLIN 11 system where wires
from the control unit end at a voice terminal and/or
data device.
A jack that connects the wires from a voice terminal
and/or a data device to the control unit.
1-6 Data Communications with the MERLIN II System

DATA CONNECTIVITY FOR Figure 1-2 shows how one department of a typical business makes use of the
A TYPICAL BUSINESS data capabilities the MERLIN II system provides. At the brokerage firm of
Bye, Loew, and Zelli, the staff of the commodities group use two types of
digital workstations connected to the MERLIN II system. This arrangement
allows them to:
• Communicate with others in the firm via electronic mail.
• Work with files from the firm’s minicomputer at their own terminals.
• Access the minicomputer or their own terminals from outside the office.
The consultants, research assistant and group secretary use a data hunt group
to access the firm’s minicomputer. The consultants and the research assistant
use an outgoing modem pool to place calls to the Porknbeans Line and other
subscription information services for commodities traders.
Data Communications with the MERLIN II System 1-7