Motorola UTA220/UTA220k, UTA220, UTA220k User Manual

UTA220/UTA220k Terminal Adapter

User Guide

Motorola ING, Inc. Part No. T0123 A
20 Cabot Blvd August 1998
Mansfield, MA 02048-1193 © 1998 Motorola

ii

COPYRIGHT

Copyright 1998 by Motorola, Inc.

Published by Motorola, who reserves the right to make improvements in the products
described in thi s manual as well as to revi se th is publ icat ion at any t ime and wit hout not ice
to any person of such revision or change.

All rights reserved. No part of this publication may be reproduced, transcribed, stored in
an electronic retrieval system, translated into any language or computer language, or be
transmitted in any form whatsoever without the prior written consent of the publisher. For
additional information contact

Motorola
20 Cabot Blvd.
Mansfield, MA 02048
[phone]

NOTICE

All titles, versions, trademarks, claims of compatibility, etc., of hardware and software
products mentione d herein are the sole property and r esponsibility o f the respective vendors.
Motorola makes no endorsement of any particular product for any purpose, nor claims
responsibility for its operation and accuracy.

UPDATES

Updates to the produ cts and the manual a re obtainable a t participa ting Motorola deal ers and
distributors, or directly from Motorola on the same terms and conditions as those offered
by Motorola to its registered customers as verified by the completion and return of the
registration form to Motorola.

STATEMENT OF APPLICATION

This manual is written for users of the Motorola UTA220/UTA220k terminal adapter.
Please read the appropri ate chapters befor e installing, changi ng any option, or opera ting the
unit.

iii

FCC REQUIREMENTS

WARNING

This equipment uses, generates, and can radiate radio
frequency energy interfering with radio communications
if not installed and used according to the instruction
manual. It has been tested and co mplies with the limits for
a Class A computing devi ce accordi ng to FCC Rules, Part

15. Operation of this equipment in a residential area may
cause interference. If it does, you must correct the cause
of the interference.

Changes or modifications to this unit not expressly
approved by the party responsible for compliance could
void the us er’s authority to operate this equipment.

SHIELDED CABLES

Shielded DTE cables should be used with this unit to
ensure compliance with Class A limits.

SPECIAL REQUIREMENTS FOR CANADA

Certain requirements exist for data communication products manufactured for use in
Canada. Principle among t hese requirement s is the applicati on of the IC stamp as des cribed
below. However, certain data communication products do not require the IC stamp nor
adherence to IC requirement s. If this is the case t he IC stamp will not be affixed to the rea r
panel of standalone units nor packaged wi th units designed fo r inse rtion in us er equipment .

Industry Canada (IC) Requirements

IC stamps are affixed to the rear of each standalone unit sold in Canada. Card units which
are installed in the user’s equipment are shipped with a stamp included. The user should
place the stamp on the outside of his equipment as close as possible to the telephone line
connector. This stamp has the certification number for that particular unit. The numbers
are different for each model.

The Industry Canada label ident ifies certi fied eq uip ment. This certi fica tion mean s that t he
equipment meets certain telecommunications network protective, operational, and safety
requirements. IC 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 t he above conditions may no t prevent degradation of service in some
situations.

iv

Repairs to certified equipment should be made by an authorized Canadian maintenance
facility desig nated 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 . For their own protection users should ensure
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 install ation connect ions
themselves, but should contact the appropriate electric
inspection authority or electrician.

Load Number

The Load Number (LN) assigned to each terminal device denotes the percentage of the total
load to be connected t o a telephone loop which is used by the device, to prevent overloading.
The termination on a loop may consist of any combination of devices subject only to the
requirement that the total of the Load Numbers of all the devices does not exceed 100.

Canadian Emission Requirements

This digital apparatus does not exceed the Class A limits for radio noise emissions from
digital appara tus set out in the Radio In terfere nce Re gulations of th e Indust ry Ca nada (I C).

Le présent appareil numérique n'emet pas de bruits radioélectriques dépassant les limites
applicables aux appareils numériques de la class A prescriptes dans le Règlement sur le
brouillage radioélectrique édicté par Industrie et Canada.

v

Preface

PREFACE AND STATEMENT OF APPLICATION

This manual is written for users of the UDS UTA220/U TA220k term inal adapter. Please
read the appropriate chapters before installing, changing any option, or operating the unit.

vi

Preface

Contents

vii

Motorola Information Systems Group Customer Information

Chapter 1. Introduction

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

Compatibility ....................................................................................................... 1-1

Other Features ...................................................................................................... 1-1

OPERATION ............................................................................................................ 1-2

PHYSICAL DESCRIPTION .................................................................................... 1-2

LED Description .................................................................................................. 1-4

FUNCTIONAL ........................................................................................................ 1-4

Chapter 2. Installation

RECEIP T INSPEC TION ............... ...... ................................................................... .. 2-1

SITE PREPARATION ................................................................ ...... ..... ................... 2-1

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

Power Connection ................................ ...... ...... ................................. ...... ...... ....... 2-2

ISDN Connection ................................................................................................ 2-2

DTE Connection ....................................................................................................... 2-3

DTE INTERFACE SPECIFICATIONS ................................................................... 2-3

Chapter 3. Getting Started

SWITCHES AND STRAPS ..................................................................................... 3-1

Cover Removal .................................................................................................... 3-1

SWITCH AND STRAP SETTINGS......................................................................... 3-2

Signal Ground ...................................................................................................... 3-2

V.35/EIA-232 Interface ....................................................................................... 3-3

Interface Card Removal ...................................................................................... 3-4

DIP Switch Options ............................................................................................. 3-5

CENTRAL OFFICE SWITCH ................................................................................ 3-6

SETUP....................................................................................................................... 3-6

Chapter 4. ISDN

ISDN BASICS .......................................................................................................... 4-1

ISDN Standards.................................................................................................... 4-1

National ISDN....................................................... .................................. ...... ..... .. 4-1

Basic Rate Interface ............................................................................................. 4-2

Terminal Adapters ............................................................................................... 4-2

ISDN Basic Rate Interface Points........................................................................ 4-2

ISDN Service ....................................................................................................... 4-3

ISDN SWITCHES ............................................................................................... 4-3

ISDN ADDRESSES AND IDENTIFIERS ......................................................... 4-5

ISDN CHANNELS ............................................................................................. 4-6

B-Channel Data Service ...................................................................................... 4-6

B-Channel Data Protocols.................................................................................... 4-7

D-Channel Signaling Protocols ........................................................................... 4-7

Layer One............................................................................................................. 4-7

Layer Two............................................................................................................. 4-8

Layer Three ......................................................................................................... 4-8

viii

Contents (continued)

Chapter 5. LCD Operation

LCD MENUS ........................................................................................................... 5-1

Main Menus .......................................................... ...... ...... ................................... 5-1

Submenus ............................................................................................................ 5-1

LCD OPERATION ................................................................................................... 5-1

Menu Traversal..................................................................................................... 5-1

Chapter 6. V.25 bis Dialer Operation

SELECTING V.25bis .......................................................................................... 6-1

OPERATION IN V.25 bis MODE............................................................................. 6-1

V.25 bis MESSAGE FRAMES................................................................................. 6-1

DTE INTERFACE PINS .......................................................................................... 6-2

DTR Pin Operation............................................................................................... 6-2

DCD Pin Operation ............................. ...... .......................................................... 6-2

CTS Pin Operation .......................................... ..... .................................. ...... ..... .. 6-3

DSR Pin Operation .............................................................................................. 6-3

COMMAND PROCEDURES .................................................................................. 6-3

COMMANDS ........................................................................................................... 6-3

Dial Command: CRN xx..x ................................................................................ 6-3

Connect Incoming Calls: CIC ............................................................................. 6-4

INDICATION MESSAGES ..................................................................................... 6-4

Call Connect Indication: CNX ............................................................................ 6-4

Incoming Call Indication: INC ............................................................................ 6-5

Response Messages ............................................................................................. 6-5

Chapter 7. EIA-366 Dialer Operation

CONFIGURATION ................................................................................................. 7-1

OPERATION ............................................................................................................ 7-1

INTERFACE SIGNAL DEFINITIONS ................................................................... 7-2

Power Indication (PWI) .............................................. ...... ..... .............................. 7-2

Call Request (CRQ) .......................................................................... ...... ...... ....... 7-2

Data Line Occupied (DLO) .................................. ...... .................................. ..... .. 7-2

Distant Station Connected (DSC)......................................................................... 7-2

Digit Signal Circuits (NB1-NB8)......................................................................... 7-2

Digit Present (DPR).............................................................................................. 7-3

Present Next Digit (PND) .................................................................................... 7-3

Abandon Call and Retry (ACR) .......................................................................... 7-4

EXAMPLE DIAL SEQUENCE................................................................................ 7-4

Chapter 8. AT Command Operation

AT COMMAND STATEMENT ............................................................ ...... ............. 8-1

AT Command Mode ........................................................................................... .. 8-1

ESCAPE SEQUENCE: + + + ............................................................................. 8-1

CREATING A COMMAND STATEMENT: AT .................................... ............. 8-2

COMMAND STATEMENT GUIDELINES ....................................................... 8-2

MONITOR DISPLAY.......................................................................................... 8-2

DTE CHARACTER ECHO: E ............................................................................ 8-2

COMMAND STATEMENT BUFFER ................................................................ 8-2

Contents (continued)

ix

Chapter 8. AT Command Operation (Continued)

BACKSPACE KEY .................................................................................................. 8-3

REPEATING A COMMAND: A/ ....................................................................... 8-3

NUMBERED COMMANDS ................................................................................... 8-3

GROUP COMMANDS ....................................................................................... 8-3

COMMAND SCOPE ........................................................................................... 8-4

Supervisor Command Mode ................................................................................ 8-4

Chapter 9. Rate Adaption

RATE ADAPTION ................................................................................................... 9-1

T-LINK...................................................................................................................... 9-1

Flow Control and Pin Options ............................................................................. 9-2

T-Link Options .................................................................................................... 9-2

V.120..................................................................................................................... 9-3

V.120 Options ...................................................................................................... 9-3

Chapter 10. BONDING

BONDING ON THE UTA220 ................................................................................. 10-1

PLACING A BONDING CALL .............................................................................. 10-2

DISCONNECTING A BONDING CALL ............................................................... 10-2

Chapter 11. Synchronous Operation

SYNCHRONOUS MODES ..................................................................................... 11-1

Synchronous Mode 1: Sync Pause Mode ............................................................ 11-1

Synchronous Mode 2: Dial Stored Number Mode .............................................. 11-1

Chapter 12. D-Channel X.25

FUNCTIONAL DESCRIPTION .............................................................................. 12-1

X.25 ..................................................................................................................... 12-1

PAD ..................................................................................................................... 12-1

ESTABLISHING AN X.25 SESSION ..................................................................... 12-2

Initialize the PAD ................................................................................................. 12-2

ATDD Command.................................................................................................. 12-2

AT@P1=P or AT@P1=D Command ................................................................... 12-2

Establishing an X.25 Virtual Connection ............................................................ 12-3

Escaping to PAD Command Mode ...................................................................... 12-4

Escaping to AT Command Mode ......................................................................... 12-4

Disconnecting the X.25 Virtu al Connection .......................... ...... ........................ 12-4

COMMON APPARENT PROBLEMS .................................................................... 12-5

Parameter 1 Changed ........................................................................................... 12-5

Parameter 2 Changed ........................................................................................... 12-5

Parameter 5 Changed ........................................................................................... 12-5

Parameter 6 Changed ........................................................................................... 12-5

Parameter 20 Changed.......................................................................................... 12-5

PAD COMMAND SET ............................................................................................ 12-5

PAD Command Format ....................................................................................... 12-5

x

Contents (continued)

Chapter 12. D-Channel X.25 (Continued)

Issuing PAD Commands ...................................................................................... 12-6

Status: ST AT......................................... .................................. ...... ..... ................... 12-6

Clear: CLR ........................................................................................................... 12-6

RESET ................................................................................................................. 12-6

Interrupt: INT ....................................................................................................... 12-7

SET....................................................................................................................... 12-7

Read: PAR? .......................................................................................................... 12-8

Set and Read: SET? ............................................................................................. 12-8

Remote Read: RPAR? ......................................................................................... 12-8

Remote Set and Read: RSET? ............................................................................. 12-9

Profile Read/Save: PROF ............................................................ ........................ 12-9

PAD Select ........................................................................................................... 12-10

FACILITIES ............................................................................................................. 12-11

Reverse Charging: R ............................................................................................ 12-11

Network User Identification (NUI) ..................................................................... 12-11

Closed User Group (CUG) .................................................................................. 12-11

Recognized Private Operating Agency ............................................................... 12-12

Flow Control Parameter Negotiation ................................................................... 12-12

PAD SERVICE SIGNALS ....................................................................................... 12-14

PAD Reset Service Signals .................................................................................. 12-15

Pad Clear Service Signals .................................................................................... 12-15

X.3 PARAMETERS AND VALUES ....................................................................... 12-16

Saving the X.3 Parameter Configuration ............................................................. 12-16

Parameter 1: Pad Recall Character ...................................................................... 12-19

Parameter 2: Echo ................................................................................................ 12-20

Parameter 3: Selection of Data Forwarding Characters ...................................... 12-20

Parameter 4: Selection of Idle Timer Delay ....................................................... 12-21

Parameter 5: Ancillary Device Control............................................................... 12-22

Parameter 6: Control of PAD Service Signals ..................................................... 12-22

Parameter 7: Action of PAD on Break from DTE .............................................. 12-23

Parameter 8: Discard Output .............................................................................. 12-24

Parameter 9: Padding after Carriage Return........................................................ 12-24

Parameter 10: Line Folding.................................................................................. 12-25

Parameter 11: Binary Speed of Local DTE ....................................................... 12-25

Parameter 12: Flow Control of PAD by Local DTE .......................................... 12-26

Parameter 13: Line Feed Insertion after Carriage Return ................................... 12-26

Parameter 14: Padding after Line Feed .............................................................. 12-27

Parameter 15: Editing.......................................................................................... 12-28

Parameter 16: Character Delete .......................................................................... 12-28

Parameter 17: Line Delete.................................................................................... 12-29

Parameter 18: Line Display.................................................................................. 12-30

Parameter 19: Editing PAD Service Signals ....................................................... 12-31

Parameter 20: Echo Mask .................................................................................... 12-32

Parameter 21: Parity Treatment ........................................................................... 12-32

Parameter 22: Page Wait ..................................................................................... 12-33

Contents (continued)

xi

Chapter 13. Softload

TA SOFTWARE ARCHITECTURE ........................................................................ 13-1

Software Sets ....................................................................................................... 13-1

Software Format .................................................................................................. 13-1

TA Power-Up Sequence ...................................................................................... 13-2

SOFTLOAD OPERATION ...................................................................................... 13-3

Set/Display Softload Password: %P1 ............................................... ...... ...... ....... 13-3

Request Softload Product Version Information: $Q ............................................ 13-4

Initiate Software Download: $Y=x ..................................................................... 13-5

Copy Active Flash: $Y2=x ................................................................................. 13-6

S59 SOFTLOAD ................................................................................................. 13-6

Swap to Alternate Software: $T=x ...................................................................... 13-8

TYPICAL LOCAL SOFTLOAD SESS ION ............................................................ 13-8

Chapter 14. Diagnostics

COMMUNICATION DIAGNOSTICS .................................................................... 14-1

GLOBAL TESTS ................................................. .................................................... 14-1

2B+D Loopback................................................................................................... 14-1

PORT TESTS ...................................................................................................... 14-2

Local Terminal Loopback .................................................................................... 14-2

Local Loopback Test ........................................................................................... 14-2

Digital Loopback Test ......................................................................................... 14-3

Bilateral Loopback Test .................................................... ..... ...... ........................ 14-5

DIAGNOSTIC STATUS DISPLAY ......................................................................... 14-6

Front Panel Keypad Test ..................................................................................... 14-6

View Product Information ................................................................................... 14-6

View Diagnostic Code ......................................................................................... 14-6

Chapter 15. Maintenance

FUSE ........................................................................................................................ 15-1

MAINTENANCE...................................................................................................... 15-1

Appendix A. Specifications

ISDN Line Type .................................................................................................. A-1

Connection Types ............................................................................................... A-1

DTE Data Rates ................................................................................................... A-1

DCE Data Rates ................................................................................................... A-1

Data Rate Adaption Protocols ............................................................................. A-1

DTE Available Interfaces .................................................................................... A-1

Switch Compatibility............................................................................................ A-1

Supplementary Services....................................................................................... A-2

Dimensions .......................................................................................................... A -2

Environmental ..................................................................................................... A-2

Power Requirements ................................................... .................................. ..... .. A-2

Power Consumption .............................................................. .............................. A-2

xii

Contents (continued)

Appendix B. Factory Default Settings

Appendix C. AT Command Set

Appendix D. Interfaces

ISDN INTERFACE .................................................................................................. D-1

INTERFACES .......................................................................................................... D-1

EIA-366A Requirements .......................................................................................... D-5

DTE INTERFACE PIN DESCRIPTIONS ............................................................... D-6

Transmit Data ................................. ..... ...... .......................................................... D-6

Receive Data ........................................................................................................ D-6

Request to Send.................................................................................................... D -6

Clear to Send ....................................................................................................... D-6

Data Set Ready .................................................................................................... D-6

Signal Ground ...................................................................................................... D-6

Data Carrier Detect .............................................................................................. D-6

Transmit Clock ............................... ................................................................... .. D-6

Receive Clock ...................................................................................................... D-7

Data Terminal Ready ........................................................................................... D-7

Ring Indicator ...................................................................................................... D-7

Appendix E. Network Option Values

Appendix F. ASCII and EBCDIC Characters

Appendix G. Abbreviations and Acronyms

Appendix H. Status and Connection Messages

Appendix I. 128K Clear Channel Leased-Line Service

Configuring D- and B-Channels............................................................................... I-1

Configuring the Port and Protocol............................................................................ I-2

Return Procedures

Index

Motorola Information Systems Group Customer Information xiii

Motorola Information Systems Group

Customer Information

Introduction

U.S.A. customers who have questions about Motorola Information Systems Group
(ISG) products or services should refer to the following sections. Non-U.S.A.
customers should contact their local Motorola Information Systems Group
subsidiary office or distributor. For a listing of our Sales and Service Offices, visit
our Web site at:
http://www.mot.com/MIMS/ISG/.

For Questions
About Your
Product Shipment

If you have questi ons about whether your shi pment is comple te or a bout its c ondition
upon receipt, please call your nearest Motorola Information Systems Group
representative, or Customer Administration at [phone], Extension 4745.

For Technical
Assistance or to
Schedule Service

Call your local Salesperson to request that a Network Services Specialist work with
you to develop an implementation and/or staging quote.

For service, if your unit is under warranty and/or you have a service contract:

Call [phone] for assistance. When you call for assistance, please have the

unit’s Model Number and Serial Number ready.

If you do not have a service contract, and your unit is no longer under warranty:

You can purchase a service contract or arrange for Time and Material services by
calling [phone] for assistance.

To Access the
Motorola ISG
Internet Web Pages

Additional company and product inf ormati on ca n be found on our Int ernet Web page
at:

http://www.mot.c om/MIM S/ISG/

For Sales-Related
Issues

Please call your local Motorola In formation S ystems Group sales office, authorized
distributor, or the Sales Assistance Center at [phone]. For a listing of our
sales offices, visit our Web site at:

http://www.mot.com/MIMS/ISG/.

For Information on
Product T rai ning

For information on classroom training, customized on-site training, or to order self­study training materials, call the Sales Assistance Center at [phone].

For Questions
About Billing

If you have a question regarding billing, call 1-800-446-0144 and select option 2.

For Comments
About the Manual

To help us improve our product documentation, please complete and return by mail,
or fax to [phone], the prepaid comment card at the end of this guide. If you
prefer, simply include your name, company, and telephone number and someone in
the documentation group will contact you to discuss any comments you might have.

xiv Motorola Information Systems Group Customer Information

T o Order Additional
Motorola ISG User
Documentation

If you would like to order additi onal copi es of Motor ola Inf ormati on Syste ms Group
user documentation, call [phone].

Customer Response Card

Motorola would like your help in improving its product documentation. Please complete and return this
card (by mail or fax to [phone]; Attention: Product Documentaton), to provide your feedback.

To discuss comments with a member of the Motorola documentation group, provide telephone
information at the bottom of this page. Thank you for your help.

Name _________________________________________________________________________
Company Name _________________________________________________________________
Address _______________________________________________________________________

_______________________________________________________________________
_______________________________________________________________________

Document Title:

UTA220/UTA220k User’s Guide

Part Number: T0123, Rev A
Please rate this document for usability:

What did you like about the document? ______________________________________________

______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________

What information, if any, is missing from the document? _________________________________

______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________

Please identify any sections/concepts that are unclear or explained inadequately.

______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________

Additional comments/suggestions. __________________________________________________

______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________

Telephone ________________________ Ext. _________________ Best time to call __________

Excellent Good Average Below Average Poor

Cut Here

FOLD HERE

DO NOT TEAR – FOLD HERE AND STAPLE

BUSINESS REPLY MAIL

FIRST CLASS PERMIT NO. 39783 MANSFIELD, MA
POSTAGE WILL BE PAID BY ADDRESSEE

Motorola University East M2-30
20 Cabot Boulevard
Mansfield, Massachusetts 02048-1193
USA

NO POSTAGE

NECESSARY

IF MAILED

IN THE

UNITED STATES

UTA220/UTA220k 1-1

Introduction

Chapter 1

Introduction

The Motorola UTA220 terminal adapter connects existing
Data Terminal Equipmen t (DTE) to the Integrated Services
Digital Network (ISDN). The UTA220 uses the ISDN Basic
Rate Interface which consists of two bearer (B) ch annels for
data and one delta (D) channel for signaling.

The UTA220 has two DTE port connectors. In addition, the
UTA220 can be ordered with two additional DTE port
connectors for EIA-232 asynchronous use or EIA-366
dialing. Each DTE has access to the 56 kbps/64 kbp s ISDN B
channels. The UTA220 functions similarly to two standard
modems in this mode.

FEATURES

The UTA220 allows maximum freedom in designing a
communications network. The UTA220 includes the
following features:

Compatibility

• Compatible with Northern Telecom DMS100 ISDN central
office switches running sof tware versions BCS-29 and above

• Compatible with AT&T 5ESS ISDN central offi ce switches
running generic programs 5E4.2 or above for TYPE A
terminals

• Compatible with central office switches running the signaling
standard National ISDN 1 (NI1)

Note: The UTA220 does not s upport elec tronic key te lephone
service (EKTS) or supplementary data services.

Other Features

• LCD option selection and operation control

• Nonvolatile storage of 10 dial strings per port

• Two sets of operating configurations saved in nonvolatile
memory

• 56 kbps/64 kbps synchronous operation

• 112 kbps/128 kbps synchronous operation using the
BONDING protocol

• V.25 bis HDLC or BISYNC call control

• EIA-366 call control on the optional upper ports

• Optional front panel UTA220 numeric keypad for dialing an d
entering options

• Integral autodialing with AT command set

1-2 UTA220/UTA220k

I

ntroduction

OPERATION

Nonvolatile memory hold s two sets of user def ined ope rati ng
configurations. Options and functions are selected from the
front panel or by AT commands. A menu driven 32- character
liquid crystal display (LCD) provides command feedback as
well as real time displays. UTA220 ope ration is mo nitored by
six light emitting diodes (LEDs) on the front panel.

The UTA220 and UTA220 have four methods of operation.

• The UTA220 is progr ammed from the front panel using three

push buttons, YES, NO, and HOME. The UTA220 has a
numeric keypad that includes the additional function keys;
CALL / HANGUP and ENTER;

• V.25 bis dialer functions and AT commands are performed
on the EIA-232 or V.35 interfaces.

• EIA-366 dialer functions are performed on the optional upper
ports.

PHYSICAL DESCRIPTION

The UTA220 is manufactured as a stand-alone desktop unit
and as a rack-mount insert ca rd. This manual ap plies to eith er
unit. Figure 1-1 shows t he front panel contr ols and indicators.

Figure 1-1. Front Panel UTA220

The standard UTA220 rear panel (Figure 1-2) houses two
25-pin D-type connect ors for the DTE interface, an 8-pi n ISDN
U modular connector (U interface), the ON/OF F toggle switch,
line fuse, and power control. The UTA220 ca n be ordered with
a V.35 interface, in which case adapters should be connected
to the 25-pin D-type connectors (Figure 1-3).

UTA220/UTA220k 1-3

Introduction

Caution: Connecting a V.35 DTE to a non-V.35 port may
damage the DTE.

Figure 1-2. Rear Panel EIA-232 Configuration

Figure 1-3. V.35 Adaptor

If the UTA220 is ordered with the addit ional upper ports, then
the rear panel will also cont ain tw o additi onal 25-p in D-type
connectors above the two lower DTE interface connectors
(Figure 1-4).

Figure 1-4. Four Port Rear Panel Configuration

1-4 UTA220/UTA220k

I

ntroduction

LED Description

The UTA220 has six LED indica to rs: B1, B2, D, DP, T, PW.
The functions of these LEDs are as follows:

B1 - On when the B1 channel has a call.
B2 - On when the B2 channel has a call.
D - This LED is for the D-Channel.

• It is off when the U connection is not established.

• It single blinks when the U connection is established.

(This may take up to 15 seconds after connection is made.)

• It double bli nks whe n communi catio ns are establ ished with

the switch.

• It is on when all B channels are available.

DP - On when the D-Channel is available for packet
calls.

T (Test) - On during the following global tests:

• 2B+D loopback

• Switch initiated tests--quiet mode and insertion loss

measurement

PW - On when the UTA220 has power.

FUNCTIONAL

The UTA220 operates on the ISDN Ba sic Rate Interface (BRI)
(2B+D). This interface provides two 64-kbps full-duplex
bearer (B) channels for ci rcuit swi tched line s. The Basic Rate
Interface also provides a 16 kbps delta (D) channel for
signaling messages. The UTA220 ada pts any data t erminal to
the ISDN Basic Rate Interface for circuit-switched data.

UTA220/UTA220k 2-1

Installation

Chapter 2

Installation

Installation of the UTA220/UTA220k is simple and straight
forward. Prior to installation, refer to Chapter 3 to either verify
or change strap options.

RECEIPT INSPECTION

After unpacking the equ ipment, check the cont ents against the
packing list. Inspect the equipment carefully for damage that
may have occurred in shipme nt. If there is damage or mate rial
shortage, contact the shipping agent and Motorola for advice
and assistance. Mo torola suggests tha t the shipping cont ai ner
and packing material be retained for future shipment.

SITE PREPARATION

The installation area should be clean and free from extremes
of temperature, humidity, appreciable shock, and vibration.

Allow ample space at the rear of the UTA220 for cable
clearance and air flow. Install the UTA220 within 6 feet of a
115 or 230 VAC grounded outlet as required for the specific
model and no farther than 50 feet from the DTE.

2-2 UTA220/UTA220k

I

nstallation

INSTALLATION

A typical installation is shown in Figure 2-1.

Figure 2-1. Typical Installation

Power Connection

Insert the power plug into a gr ounded 115 or 220 VAC outlet
as required for the speci fic model. The UTA220 i s now ready
to be turned on and programmed.

Caution: Do not connect the UTA220 to the ISDN line until
the UTA220 has been programmed with the correct switch
settings. Refer to Ce ntral Office Switch in Chapter 3 fo r details.

ISDN Connection

To connect the UTA220 to the ISDN line, insert one end of the
supplied cable into the UTA220 ISDN U jack. I nsert the other
end into the ISDN (RJ45) jack.

Note: An NT1 device is not required.

UTA220/UTA220k 2-3

Installation

DTE Connection

Insert each DTE cable into a DTE connector. Insert the
opposite end into the DTE. Secure the connect screws to
complete the connection.

DTE INTERFACE SPECIFICATIONS

The DTE interface to the UTA220 is through an EIA-232
D/E 25-pin D-type connector. The UTA220 can also be
configured for V.35 operation. It is also available with V.35
interfaces and with two additional ports for EIA-366 dialing,
or EIA-232C operation.

2-4 UTA220/UTA220k

I

nstallation

UTA220/UTA220k 3-1

Getting Starte

d

Chapter 3

Getting Started

This chapter provides instructions for setting switches and
straps plus a quic k programming se tup for the DMS100 or the
5ESS central off ice switch or switches running National IS DN
1 (NI1).

Caution: Do not connect the UTA220 to the ISDN line until
the UTA220 has been programmed for the correct switch,
switch version, Terminal Endpoint Identifier (TEI) numbers,
and Service Profile Id entifiers (SPIDs). These ar e provided by
the telephone company at subscription time. Use of numbers
other than those as signed or failure to pro gram these numbers
in the UTA220 can result in error conditions between the
central office switch and the terminal adapter.

SWITCHES AND STRAPS

The unit is factory configured to current industry standards.
Because of different environments, some terminal adapters
may require stra p or switch changes. This s ection describes the
strap and switch options and how to use them.

Caution: Electrostatic discharge (ESD) can damage
electronic components.

Cover Removal

To select or inspect the strap option, first remove the unit’s
cover.

Warning: Do not remove the cover unless both the power cord
and ISDN line are unplugged.

Place the UTA220 on its side on a fl at surface. Insert a medium
size flat screwdriv er blade in one of the bot tom rear latch slots.
DO NOT PUSH the screwdriver. Lightl y pry the handl e away
to disengage the lock prong from the lock clip as shown in
Figure 3-1. Assist by pushin g the cove r from th e chassi s with
your fingers on the unit rea r edges. Repeat this procedur e with
the remaining three latch slots.

3-2 UTA220/UTA220k

Getting Started

Figure 3-1. Cover Removal

To replace the cover, align the loc k clips, re ar gui de grooves ,
and front lock tabs. Press the cover in p lace until the lock
prongs engage the lock clip.

SWITCH AND STRAP SETTINGS

The following options are selected by switches or straps
located on the PC boards inside the UTA220 housing. To
change the strap set ting, lift the jumper st rap connector off and
reinsert it i n the new positi on. Figure 3-2 sho ws a typical strap
application.

Figure 3-2. Typical Strap Application

Caution: Only personnel familiar with DIP switch selection
should change switch positions or the ground strap from
factory settings. Changes should be made only during setup.

Signal Ground

Signal ground is normally isolated from frame ground
(factory). If int erference exists, connect signal ground to frame
ground by moving the strap.

UTA220/UTA220k 3-3

Getting Starte

d

(Figure 3-3).

Figure 3-3. Strap and Switch Locations

V.35/EIA-232 Interface

The V.35/EIA-232 interface cards can conform to V.35
(factory) or EIA- 232 D/E by means of t wo sli de swi tches and
a DIP switch. Slide the switches toward the front of the
UTA220 to select V.35 and toward the rear of t he UTA220 to
select EIA-232 D/E (Figure 3-4).

To complete the select ion of EIA-232 D/ E, set the DIP switc h
as indicated in Table 3-1. The followin g sections descri be how
to change DIP switch settings.

Table 3-1:

DIP Switch Settings for EIA232 D/E Operation

DIP Switch Position

1234
OFF OFF ON ON

3-4 UTA220/UTA220k

Getting Started

Note: Ensure that both slide switches on the interface card
are in the same position.

Figure 3-4. V.35 EIA-232 interface Card

Interface Card Removal

The port 1 V.35/EIA-232 i nterface card must be removed from
the UTA220 to change the DIP switch settings.

Note: Do not remove the port 2 inte rface card. The port 2 DIP
switch can be accessed without removing the card.

UTA220/UTA220k 3-5

Getting Starte

d

Remove the two sc rews from th e port 1 inte rface card and pull
it straight up (Figure 3-5). To re-assemble, align the interface
card to the UTA220 PC board, pres s down, and inse rt the two
screws.

Figure 3-5. V.35 Switch Location

DIP Switch Options

The V.35/EIA-232 interface card has an eight-position DIP
switch on the bottom (Figure 3-5). The port 2 DIP switch
settings can be changed without removing the port 2 inte rface
card. Note the orientation of the switch when changing the
settings on port 2. The DI P switch allows y ou to transpos e the
Ring Indicate (RI) a nd Local Loopback pins (LL). Normal ly,
RI is found on pin J and LL is foun d on pin L. However, thes e
can be transposed (Table 3-2).

*default

Table 3-2:

V.35 Ring Indicate Local Loopback Pinouts

DIP Switch Position Pin Function

& Location

1234RILL
ON* ON* OFF* J* L* ON

3-6 UTA220/UTA220k

Getting Started

Transmit clock B can be disconnected from pin AA/2 by
turning switch position 6 to OFF. Switch positions 5, 7, 8
should be left in their factory settings (Table 3-3).

Note: Extreme care should be taken to re-align the interface
card when inserting it in the UTA220.

CENTRAL OFFICE SWITCH

The UTA220 is designed for eas y programming and operation.
Using the front panel LCD display and push-button, the
UTA220 can be set up for one of the following central-office
switches:

• National ISDN-1

• NTI DMS100, BCS-30, BCS-31/32 or

• AT&T 5ESS, 5E4.2, 5E5, 5E6

Programming the UTA220 requir es the following information,
which is provided by the telephone company:

• Switch type and version

• Terminal Endpoint Identifiers (TEI)

• Service Profile Identifiers (SPID)

• Directory Number (DN) st rings (only supplied with Nat ional

ISDN and NTI DMS100 lines)

This information identifies the UTA220 to the telephone
company. Until the UTA220 has been programmed with this
information, the telephone company will not recognize the
terminal adapter, and calls cannot be placed.

SETUP

Caution: For proper operation of the UTA220, enter
the following options exactly as given by the
telephone company.

Table 3-3: V.35 Transmit Clock Pinout

DIP

Switch Position

Pin Function

& Location

5678TC

OFF* ON* OFF* ON* AA/2*

OFF ---

UTA220/UTA220k 3-7

Getting Starte

d

Setup Step 1

Plug the UTA220 into the power outlet. Turn the power switch
on the rear panel ON.

Note: Do not connect the UTA220 to the ISDN line until the
UTA220 has been properly programmed.

The LCD displays the banner:

ISDN TERMINAL ADAPTER

Setup Step 2
To program the UTA220, perform the steps in Ta ble 3-4. Use

the HOME key any time to back up to correct a mistake.

Table 3-4: Programming Steps

STEP LCD SCREEN

DISPLAY

ACTION

1 ISDN

TERMINA L ADAPTER

Press YES or NO key to advance to the next display.

2 DIAL/HANGUP

OPTIONS?

Press NO.

3 STATUS DISPLAYS? Press NO.
4 CONFIGURATION

OPTIONS?

Press YES.

5 SWITCH CONFIG

OPTIONS?

Press YES.

6 SWITCH TYPE

OPTION?

Press YES.

7 NATIONAL ISDN

CHANGE?

National ISDN NTI DMS100 AT&T 5ESS
Press NO.

Continue programming
with STEP 9.

Press YES until "NTI
DMS100" is displayed,
then press NO.

Press YES until
"AT&T 5ESS" is
displayed, then press
NO.

8 WILL DESTROY ALL

NET OPTS, CONT?

Press YES. The display momentarily shows ’RESETTING SWITCH OPTIONS"
while it changes the switch options to the default values for the selected switch
type.

9 SWITCH TYPE OPTION? Press NO.

10 SWITCH VERSION

OPTION?

National ISDN NTI DMS100 AT&T 5ESS
Press No. Continue

programming with STEP

13.

Press YES. Press YES.

11 <default version>

VERSION. CHANGE?

This screen displays the d efa ult ve rsio n fo r th e sw itc h typ e yo u se lecte d ab ove .
Press YES until the correct version is displayed. Press NO to select the switch
version choice. (refer to Chapter 4, ISDN Switches section.)

12 SWITCH VERSION

OPTION?

Press NO.

13 D-CHANNEL

OPTIONS?

Press YES.

3-8 UTA220/UTA220k

Getting Started

14 D-CHANNEL PROV

OPTIONS?

Press NO.

15 D-CHANNEL

LAPD OPTIONS?

Press YES.

16 CURRENT PORT = 1

CHANGE?

Press NO.

17 P1:X.25 TEI=DIS

CHANGE?

If D-channel X.25 is desired, follow the selections described in Step 18 for entering
a TEI value. For AT&T 5ESS switches, this setting is normally "AUTO". For NT
DMS-100 and NT-1 switch es, a manua l T EI (0- 63) va lue is nor mally r equi red. If
D-Channel X.25 is not desired, press NO.

18 P1: D ATA TEI = AUTO.

CHANGE?

There are three classes of possible DATA TEI value settings: "AUTO", "DIS", and
0-63. Use one of the setup cases below that matches your TEI value.

"AUTO"
TEI:

Press NO to advance to the next menu. The "AUTO"
value is used to select a dynamically assigned TEI.
"AUTO" is the factory default and should be correct
in most situations.

"DIS"
TEI:

Press YES to scroll through the supported TEI
values until "DIS" is displayed. Press NO to advance
to the next menu.

0-63
(UTA220k):

Press YES twice "00" is displayed. Press the keypad
number keys un til the entire number has be en keyed
in. If the number is one digit long, press the
appropriate number key, then press ENTER.

0-63
(UTA220):

Press YES until the first digit of the value is displayed
then press NO to accept the digi t and advance to
the next digit. Con tinue to do this until the entire
number has been keyed in. If the number is one digit
long, enter the first digit, then press YES unt il the
character "_" is displayed to the right of the digit.
Press NO to enter the TEI number.

Note: If only one circuit-switched call at a time is necessary and the call will always
be placed to or from the same Directory Number, then only one of the TEIs should
be enabled and the other disabled.

19 P1:_____________

SPID. CHANGE?

- The SPID only needs to be configured if the TEI is not disabled.

- Enter the SPID string in the same manner as the TEI. The SPID value can be up
to 20 digits in length.

20 P1:_____________

DN. CHANGE?

- The Directory Number (DN) only needs to be configured if the TEI is not disabled.
The DN is optional for AT&T 5ESS switch types.

- Enter the DN string in the same ma nn er as the TEIs and SPIDs. Like the S PID
strings, the DN strings can be up to 20 digits in length.

21 CURRENT PORT = 1

CHANGE?

Press 2.

22 P2: X.25 TEI=DIS

CHANGE?

Press NO

23 P2: DATA TEI = AUTO

CHANGE?

Same as Step 18.

24 P2:_____________

SPID. CHANGE?

- The SPID only needs to be configured if the TEI is not disabled.

- Enter the SPID string in the same manner as the TEI. The SPID value can be up
to 20 digits in length.

25 P2:_____________

DN. CHANGE?

- The Directory Number (DN) only needs to be configured if the TEI is not disabled.
The DN is optional for AT&T 5ESS switch types.

- Enter the DN string in the same ma nn er as the TEIs and SPIDs. Like the S PID
strings, the DN strings can be up to 20 digits in length.

26 If you have a two-port unit, then continue with STEP 37.

Table 3-4: Programming Steps (Continued)

STEP LCD SCREEN

DISPLAY

ACTION

UTA220/UTA220k 3-9

Getting Starte

d

Note: Some LCD screen displays require different actions
depending on the telephone company’s switch type.

Setup Step 3

Insert the ISDN line i nto th e I S DN U j ack l ocat ed on the r ear
panel.

27 CURRENT PORT = 2

CHANGE?

Press 3.

28 P3: X.25 TEI=DIS

CHANGE?

Press NO

29 P3: DATA TEI = DIS.

CHANGE?

Same as Step 18.

30 P3:_____________

SPID. CHANGE?

- The SPID only needs to be configured if the TEI is not disabled.

- Enter the SPID string in the same manner as the TEI. The SPID value can be up
to 20 digits in length.

31 P3:_____________

DN. CHANGE?

- The Directory Number (DN) only needs to be configured if the TEI is not disabled.
The DN is optional for AT&T 5ESS switch types.

- Enter the DN string in the same ma nn er as the TEIs and SPIDs. Like the S PID
strings, the DN strings can be up to 20 digits in length.

32 CURRENT PORT = 3

CHANGE?

Press 4.

33 P4: X.25 TEI=DIS

CHANGE?

Press NO

34 P4: TEI = DIS.

CHANGE?

Same as Step 18.

35 P4:_____________

SPID. CHANGE?

- The SPID only needs to be configured if the TEI is not disabled.

- Enter the SPID string in the same manner as the TEI. The SPID value can be up
to 20 digits in length.

36 P4:_____________

DN. CHANGE?

- The Directory Number (DN) only needs to be configured if the TEI is not disabled.
The DN is optional for AT&T 5ESS switch types.

- Enter the DN string in the same ma nn er as the TEIs and SPIDs. Like the S PID
strings, the DN strings can be up to 20 digits in length.

37 CURRENT PORT = 4

CHANGE?

Press HOME.

38 D-CHANNEL LAPD

OPTIONS?

Press NO.

39 D-CHANNEL PROVISION

X.25 OPTIONS?

Press NO.

40 D-CHANNEL OPTIONS? Press NO.
41 MULTIFRAME SYNC =

__________CHANG E ?

Press NO.

42 FR O N T PA NE L LOCK

OPTION?

Press NO.

43 SAVE SWITCH AND

GLOBL TO NONVOL?

Press YES to save the switch configuration. The display momentarily shows
"SAVING" while it is saving the options to nonvolatile memory.

44 RESTART NETWORK

LINK?

Plug telephone cable into ISDN U jack on rear of unit, then press YES.

Table 3-4: Programming Steps (Continued)

STEP LCD SCREEN

DISPLAY

ACTION

3-10 UTA220/UTA220k

Getting Started

UTA220/UTA220k 4-1

ISD

N

Chapter 4

ISDN

This chapter provides information to help you set up and use
your Terminal Adaptor (TA) . For us er s unf am il ia r wit h TAs,
some fundamental Integrated Services Digital Network
(ISDN) concepts are pre sented first. If you are alre ady familiar
with ISDN you may skip over this section, but the ISDN
Switches and the ISDN Addresses and Identifiers sections
contain informati on pertinent to the switch configurat ion of the
TA and should be reviewed.

ISDN BASICS

ISDN is a global sys tem that provi des a vari ety of high -speed
digital telecommunication services including voice, data,
images, and video, integrated on one network. As ISDN
evolves it will p rovide the same types of services as the existing
analog networks (voice a nd low-speed data), plus new service s
made possible by recent advances in computers and digital dat a
communications.

ISDN is based on standards t hat define t he interfaces be tween
the network and the equipment connected to it. This
standardization permits communication between ISDN
systems and equipment manufactured by different vendors
world wide.

ISDN Standards

ISDN standards are set by the International Consultative
Committee for Telegraph and Telephone (CCITT), an
organization that establishes communications
recommendations under the auspices of the United Nations.

Because ISDN technolo gy advances faster than the CCITT ca n
establish standa rds, a number of de-f acto sta ndards have been
developed by manufacturers of telephone equipment. While
these set the precedence for CCITT standards eventually
agreed to, there are enough differences that those who set up
ISDN equipment (such as TAs) must be aware of them.

National ISDN

The U.S.A. and Canada have an ISDN standard for North
America called National ISDN. The first version of this
standard, National ISDN One (NI-1), is being adopted by
equipment manufacturers and net work providers . When f ully
deployed, NI-1 will make understanding and configuring
ISDN equipment easier and more efficient.

4-2 UTA220/UTA220k

I

SDN

Basic Rate Interface

Several types of ISDN network services are available. The
most common is Basic Rate Interfac e (BRI). BRI provides two
B-channels (bearer chan nels) and one D-channel (used to place
and release calls on the network).

B-channels, which operate at 64 kbps full-duplex, carry end­to-end data between network terminals. B-channels can be
either circuit-switched (dial-up), allowing each call to be
placed to different endpoints, or permanently connected
(nailed) to a single endpoint. In some application s, B-channels
can also be used to carry packet-switched data, where each
frame of data can dynamically be sent to different network
users. The TA does not support packet-switching on a
B-channel.

The D-channel is primarily a control channel between the
network and the terminal device (such as a TA).

Terminal Adapters

Terminal adapters attach standard data terminals and voice
telephones to the ISDN, allowing them to send and receive
calls and data via the ISDN. Some terminal adapters (but not
the UTA220) support voice service, allowing a standard
(analog) telephone set to be connected to the ISDN.

The UTA220 operates on the ISDN BRI. It provides circuit­switched data communications using circuit-switched
B-channels for data, and uses the D-channel for signal ing only.

ISDN Basic Rate Interface Points

BRI points and the associated devices found on customer
premises are shown in Figure 4-1. The boxes in the diagram
represent devices, and the vertical lines represent defined
interface points. There are two types of DTEs represented in
the diagram:

• TE1 devices have a built in ISDN interface.

• TE2 devices do not have a built in ISDN interface, and

require a TA to interface with the ISDN.

The data terminal devices (DTEs) are located in the left of the
diagram. The TA is connected to the ISDN at the U inter face.
An NT1 device is not required; the NT 1 func ti on i s bui lt into
the UTA220.

UTA220/UTA220k 4-3

ISD

N

ISDN Service

Figure 4-1. ISDN Devices and Reference Points

To use the ISDN, you must subs cribe to a network service. T he
available option s depend on th e car rier ( tele phone co mpany) ,
but some generally available options are:

• Types of calls supported (voice, data, packetized data)

• Circuit-switched (dial-up) or permanent (nailed) lines

• One or two B-channels

• A telephone number for each B-channel, or one number for
both channels

ISDN SWITCHES

The device controlling the ISDN line is the central office
switch. It is usually owned by the network provider (e.g., the
telephone company). Each switch has its own format and
procedures for the D-channel protocols used to establish and
control calls. (More on D-channel protocols later.) There are
three main ISDN switch standards used in North America:
AT&T, Northern Telecom (NTI), and NI-1. Their basic
functions are similar, but each has its own set of special
features and parameters .

Before using the TA, you must configur e the uni t for a swi tch
type. The TA will operate with AT&T, Northern Telecom
(NT), or any switch run ning Nationa l ISDN-1. Cent ral Offic e
(CO) switches can be loaded with different software versions.
The TA supports AT&T switches runni ng versions 5E4.2 and
later, and NT switches running versions BCS29 and later.

4-4 UTA220/UTA220k

I

SDN

AT&T switches define Si ngle Term and Multipl e Term modes
of operation for the TA. AT&T switches support Point-to­Point, Multi-Point ser vices and NI operat ion depending on the
software version loaded in the switch. The switch can also
operate in custom mode to support modes other than the
default. Table 4-1 shows AT&T switch versions, supported
modes, and default modes.

When you set the TA for Point-To-Point switch operation, it
runs in the single term mode an d only one TA may be attached.
Because only one TA is attached, Servic e Prof ile Identifiers
(SPIDs) and Directory Numbers (DNs) are not needed to
identify the TA. This is called non-initializing mode. This
mode functions on a multi-point switch; however, the switch
requires the TA to present its DN when it makes calls to
distinguish it from other TAs on the line. Thus the DN must
be properly configured in the TA in this instance.

Normally on a multi-point line, you configure the TA for
multi-point operation. This causes the TA to run in the
multi-terminal-initializing mode; SPID numbers are required.

To configure the TA for NI1 operation, select NI1 as the switc h
type.

Note: If you are using BONDING with t he secondary call port,
the DN must be ent ered so that it can be provided to the re mote
TA.

Table 4-1: AT&T Switch Modes

Switch Version Default Mode Custom Mode

5E4.2 Point-to-Point None
5E5 Multi-Point Point-to-Point
5E6 Multi-Point Point-to-Point
5E7 Multi-Point Point-to-Point
5E8 NI1 Point-to-Point

and Multi-Point

5E9 NI1 Point-to-Point

and Multi-Point

UTA220/UTA220k 4-5

ISD

N

NT switches support three Protocol Version Control Issue
Codes (PVCICs), depending on th e software version loaded in
the switch. Refer to Table 4-2.

Set the Switch Version option on the TA according to Table
4-3.

ISDN ADDRESSES AND IDENTIFIERS

The TA contains several st ored nu mbers –SPID, DN, and TEI
(Terminal Endpoint Iden tifier)

–used by the network to identify

the TA.
Each logical ISDN l ink has an SPID that d efines the profile of

services and parameters used by the terminal. The SPID is
selected by the net work carrier and must be co nfigured into the
TA before it can be u sed. The SPID is a string of char acters or
digits, depending on the switch.

The DN is part of the service profile and is analogous to the
telephone number on the standa rd telephone network. The DN
identifies incoming calls . On some switches (NTI and NI-1),
the DN must also be configured into t he TA; on other switches
(AT&T), the DN is not required.

Table 4-2: Northern Telecom Switch Modes

Switch Version Default Mode Other Modes

BCS29 PVCIC=0 None
BCS30 PVCIC=0 None
BCS31 PVCIC=1 PVCIC=0
BCS32 PVCIC=1 PVCIC=0
BCS33 PVCIC=1 PVCIC=0
BCS34 PVCIC=2 PVCIC=0, 1
BCS35 PVCIC=2 PVCIC=0, 1
BCS36 PVCIC=2 PVCIC=0, 1

Table 4-3: UTA220 Switch Settings

PVCIC TA Switch

Type

TA Switch Version

0NTI

DMS100

DMS100 PVC-IC0

1NTI

DMS100

DMS100 PVC-IC1

2 National

ISDN

N/A

4-6 UTA220/UTA220k

I

SDN

The TEI is used to identify the terminal device. In most
applications, the network switch automatically assigns a TEI
to the TA when the connection is est abl i she d; ot her w is e, you
must enter the TEI before connecting to the network.

If your switch permits it, the UTA220 allows you to use one
SPID and one TEI on simultaneous calls. AT&T switches
allow two calls per SPID. With t his support you ca n configure
two or more ports to share a DN.

Note: To use this feature, configure each port with the same
SPID and DN, enable one port’s TEI, and disable the TEI on
the remainin g port(s).

The UTA220 also allows you to use multiple DNs on the same
SPID if your switch sup ports it. NT switches suppor t up to four
DNs per SPID.

Note: To use this feature, configure both ports with the same
SPID and different DNs, then enable one port’ s TEI and disable
the other’s.

ISDN CHANNELS

As previously mentioned, there ar e three channels available on
the ISDN Basic Rate Interface: two 64 Kbps B-channels and
one 16 Kbps D-channel. The B-channels are the primary means
of carrying user information, whether voi ce or data. Voice data
must be sent on a B-channel. The B-ch annel also provides the
most efficient p ath fo r d ata co mmun icati ons, si nce it h as four
times the data capacity of the D-channel.

The D-channel is the cont rol c hannel betwee n the TA and the
network switch. It is used mainly for exchanging signaling
messages with the switch, to perform functions like setting up
and releasing calls.

Note: The UTA220 supports only data calls.

B-Channel Data Service

When a B-channel data call is placed, the switch allocates a
free B-channel between the TA and the remote DCE (e.g., the
TA at the other end of the ISDN link). This B-cha nnel acts like
a bit-pipe between two network users, operating
synchronously at 64 Kbps. In most cases, the ISDN network
does not know about the format of the data sent on the
B-channels.

There are several ways to use the B-channel to pass data. In

the “clear channel” mode, data from the DTE goes directly
onto the B-channel. However, to use this mode, your DTE must
also operate synchronously at 56 or 64 kbps.

UTA220/UTA220k 4-7

ISD

N

B-Channel Data Protocols

To allow greater flexibility for your DTE, there are three rate
adaption protocols available f or use on the B-chan nel: TLink ,
V.120, and Bonding. These protocols allow your DTE to
operate both synchronously and asynchronously, and at a
different speed than the B-channel.

• TLink is a Northern Telecom proprietary rate adaption

protocol. It supports synchronous and asynchronous rate
adaption at a variety of speeds.

• V.120 is a CCITT protocol that supports synchronous and

asynchronous rate adaption, and also provides link-layer
error control. Altho ugh errors on a digital networ k are more
rare than on an analog telephone line, they are possible.
V.120 provides an end-to-end protocol for detecting and
correcting any such errors. V.120 also performs buffering
and can thus support flow control to and from the DTE.

• BONDING is a new protocol standard from the Band width

ON Demand INteroperability Group. It combines the
bandwidth of several 56 kbps or 64 kbps channels, and can
bond from 2 to 31 channels at once, if the channels are
available. The high sp eed data, whic h must be a multiple of
56 kbps or 64 kbps, comes in on the DTE interface and is
split to the vari ous channels. On th e opposite e nd the data is
recombined into t he original data stream and sent to the DTE
interface.

To use a rate adaption protocol, the DCEs (e.g., TAs) at both
ends of the link must suppor t it and must be c onfigured to use
it. In general, since it is more flexible a nd supports error
control, V.120 shoul d be use d for most appl icat ions, and thus
it is the default protocol in the UTA220.

D-Channel Signaling Protocols

The D-channel conveys signaling information and, optionally,
packet-switched data, to the network switch. This data is
passed in message blocks defined by the ISDN signaling
protocols. These protocols vary somewhat depending on the
network switch installed at the telephone company's central
office. As mentioned earlier, several de-facto protocol
standards, are used for the D-channel signaling between the
TA and the switch.

The TA signaling protocols f unction on thr ee protoco l layers.
Each of these layers is described below.

Layer One

The physical layer includes components a nd interfaces needed
to provide a physical communications path. All ISDN switches
use the same physical layer protocols for the Basic Rate
Interface, which are base d on CCITT Recommendati on I.430.

4-8 UTA220/UTA220k

I

SDN

Layer Two

The data link layer ensures error-free transmission of
D-channel messages between the terminal and the network
switch. The link layer in effect provides a vi rtual error-free
connection for the ne xt higher protocol layer to us e. The LAPD
protocol is the error detection and correction mechanism for
layer two. Layer two protocols are based on CCITT
recommendation Q.921, and are almost identical. Minor
differences do exi st , howe ver , pr imar i ly in how the protocols
respond to certain very unlikely error conditions.

Layer Three

The network layer consists of signaling messages passed
between the terminal and the network, using the dat a link layer.
These messages communicat e cal l set up (di aling) and re lease
messages from the TA, call progress information from the
network, and messages concerning special call-related
features. Layer three of the D-channel can also be used to
exchange packetized da ta using X.25, if the TA and the switch
are set up to allow it.

All layer three protocols are based on CCITT
Recommendation Q.931. However, the protocol used depends
on the brand and version of the network switch. There are
differences in the exact proce dure s use d by ea ch switc h to s et
up and release calls. In addition, because switches are
manufactured by competing companies, each switch offers a
different set of extra features. These features are called
supplementary services.

Unfortunately, each vendor implements these features
differently. Also, there are different versions of eac h of the
switches, each of whi ch implements a diff erent set of feat ures.
As a result, you must configure your TA for the particular
switch type and version so that the TA can use the correct
signaling protocol for that switch. The switch type and version

are two of the most important network parameters in the TA.

UTA220/UTA220k 5-1

LCD Operation

Chapter 5

LCD Operation

The UTA220 has an easy-to-use front panel with a Liquid
Crystal Display (LCD). You can monitor TA status, perform
operations, and program the TA without using a terminal or
computer.

LCD MENUS

The LCD menus are arranged in multiple levels. Menu h eaders
may to more menu head ers, opti ons scre ens or a ction scre ens.
When the NO key is pressed while a menu header is displayed,
the LCD advances to the next menu header. When the YES
key is pressed, the menu descends one level in the menus.

Main Menus

The Main Menu headers are :

• DIAL/HANGUP OPTIONS? - to dial manually or to dial
previously stored telephone numbers and to hang up.

• STATUS DISPLAYS? - to view the stat us of e ach dat a port
call.

• CONFIGURATIONS OPTIONS? - to program switch and
port options.

• CONFIGURATION LOAD/SAVE OPTIONS? - to save the
switch and port configuration settings or to retrieve the
factory settings or stored settings.

• DIAGNOSTIC OPTIONS? - to run tests, restar t the network
and view product information.

Submenus

A menu includes menu headers, action screens, or option
screens. Action screens let you perform an action, such as
dialing. Option screens show settings and allow changes.
Options may b e set from mult iple choice lists or by en tering
data.

LCD OPERATION
Menu Traversal

After power-up, the LCD displays the sign-on banner: ISDN
TERMINAL ADAPTER. To enter the Main Menu level, press
the YES or NO key. Whenever the LCD is on the Main Menu
level, the sign-on b anner can be dis played by pressi ng HOME.

In general, pressing NO moves the display vertically down a
column (Table 5-1) and pressing YES moves the display
horizontally across the columns (one level deeper).

5-2 UTA220/UTA220k

L

CD Operation

At the last Main Menu screen, pressing NO displays the first
Main Menu screen. At the last screen at any other level,
pressing NO moves the display up one level.

The deepest screen (r ightmos t, in t he tab le) t ypical ly cha nges
an option or performs an action. Pressing YES at this screen
begins the change p rocess on the opt ion, or performs an action.

Table 5-1. Menu Option Summary

Main Level Level 1 Level 2 Level 3 Level 4 Description

ISDN
TERMINAL

ADAPTER
DIAL/HANGUP
OPTIONS?

Current Port:
n

Pn:ENTER
NUMBER TO
DIAL?

Pn:---------­ ENTER#.
CHANGE

n=current port. Note 2
Pressing Call/Hangup from

anywhere in menu a dvances to
ENTER NUMBER screen

Pn:REDIAL? x n=current port

x=last number dialed. Note 2

Pn:DIAL
STORED NUM­BER?

Pn:DIAL TEL #t?
s

n=current port
s =stored number t=0-9 storage
index. Note 2

Pn:VIEW/
CHANGE
STORED TEL
NUM?

Pn:x. Tel #t.
CHANGE?

n=current port
x= 13 digits of the phone num-

ber. Phone number can contain
40 digits, scrolled 1 digit / sec.
t=0-9 storage index. Note 3

Pn: HANGUP? n=current port. Note 2
STATUS
DISPLAYS?

Current Port= n.

Change?

OR

n=current port
CALL STATUS SCREEN
s =IDLE, SETTING UP,
DIALING, PROCEEDING,

RINGING, ECHO
CANCELING ONLINE,
INCOMING CALL,
ANSWERING,
DISCONNECTING, BUSY,

DISCONNECTED

Pn:ONLINE

prmd

p=CLEAR, BOND, T-LINK,
V.120

m=SYNC-1, SYNC-2, ASYNC
r =300, 1200, 2400, 4800, 9600,

1k, 38k, 48k, 56k, 57k, 64k,
112k, 128k

d=8E, 8O, 8N, 7E, 7O, 7N, 7M
This screen appears once a call

is connected. Note 4

CONFIGURA­TION

OPTIONS?

SWITCH

CONFIG

OPTIONS?

SWITCH TYPE
OPTION?

x.CHANGE? x=NATIONAL ISDN, NT

DMS100, AT&T 5ESS
SELECTED

WILL DESTROY
NET OPTS,
CONT?

RESETTING
SWITCH OP­TIONS

The query appears only if the
network type has changed.

SWITCH
VERSION
OPTION?

x VERSION.
CHANGE?

x=5ESS MULTIPOINT, 5ESS
PT TO PT, (if switch type=ATT)

x=DMS100 PVC IC-0, DMS100
PVC IC-1 (if switch type = NT)

Navigation button
directions:

YES NO HOME

UTA220/UTA220k 5-3

LCD Operation

SWITCH

CONFIG

OPTIONS?

(cont.)

B-CHANNEL
OPTIONS?

B-CHANNEL
PROV

OPTIONS?

B1 = x
CHANGE?

x= NONE, PERMANENT

B2 = x
CHANGE?

x= NONE, PERMANENT

D-CHANNEL OP­TIONS?

D-CHANNEL
PROV

OPTIONS?

D-CHAN PROVI­SION x. CHANGE?

x= NONE, X.25

D-CHANNEL
LAPD

OPTIONS?

CURRENT PORT
= n. CHANGE?

n=1 or 2

Pn:X.25 TEI = x.
CHANGE?

n=CURRENT PORT
x= 0-63, DIS, AUTO

Pn:DATA TEI =x
CHANGE?

n=CURRENT PORT
x= 0-63, DIS, AUTO

Pn:x SPID.
CHANGE?

n=CURRENT PORT
x=SPID, up to 20 digits

Pn: x DN.
CHANGE?

n=CURRENT PORT
x=DN, up to 20 digits

D-CHAN
PROVISION
X.25

OPTIONS?

RX WINDOW
SIZE=x.

CHANGE?

x=1 - 7

TX WINDOW
SIZE=x.

CHANGE?

x=1 - 7

RX PACKET
SIZE=x.

CHANGE?

x=128, 256

TX PACKET
SIZE=x.

CHANGE?

x=128, 256

PVC NUMBER =x
CHANGE?

x=0 - 255

INC LOGICAL
CHAN NUM=x.

CHANGE?

x=0 - 255

2-WAY LOG
CHAN NUM=x.

CHANGE?

x=0 - 255

OUT LOGICAL
CHAN NUM=x.

CHANGE?

x=0 - 255

SEQUENCE NUM­BER MOD=x.

CHANGE?

x=8, 128

FRONT PANEL
LOCK

OPTION?

ENTER PASS­WORD ------­CHANGE?

Enter password to gain access
to lock option screen.

FRONT PANEL
LCK = x
CHANGE?

x= UNLOCKED, OPTIONS,
OPT/ACT

SAVE SWITCH
AND GLOBL TO
NONVOL?

SAVING

Table 5-1. Menu Option Summary (Continued)

Main Level Level 1 Level 2 Level 3 Level 4 Description

Navigation button
directions:

YES NO HOME

5-4 UTA220/UTA220k

L

CD Operation

PORT CONFIG

OPTIONS?

CURRENT
PORT=n
CHANGE?

n=1 - 2

Pn:LOAD FROM
NONVOL?

Pn:LOAD FROM
NONVOL x.

CHANGE?

LOADING n=current port

x= 0, 1

Pn:LOAD FROM
FACTORY

PROFILE?

Pn:LOAD
FACTORY

PROF x.
CHANGE?

LOADING n=current port

x= 0, 1

Pn: ANSWER
OPTIONS?

Pn:AUTO
ANSWER=x

CHANGE?

n=current port
x= ON, OFF

Pn: RINGS
UNTIL ANS =x.

CHANGE?

n=current port
x= 0 - 255

Pn:DTE
OPTIONS?

Pn:xxx.
CHANGE?

n=current port
x= SYNCHRONOUS 1,

SYNCHRONOUS 2, ASYN­CHRONOUS

Pn:DTE SPEED
=xxx
CHANGE?

n=current port
n=300, 1200, 2400, 4800, 9600,

19.2k, 38.4k, 48k, 56k, 57.6k,
64k, 112k, 128k

Pn:WORD
LENGTH= x
CHANGE?

n=current port
x= 7, 8

Pn:PARITY=x .
CHANGE?

n=current port

x= NONE, EVEN, ODD, MARK
Pn:
CHARACTER

ECHO = xxx.
CHANGE?

n=current port

x= OFF, ON

Pn: X25XPAR=x.
CHANGE?

n=current port

x=YES, NO
Pn: DTE

GUARD= x.
CHANGE?

n=current port

x= OFF, ON

Pn: DTE CMD
AND

MESSAGE
OPTIONS?

Pn:DIALER
CMDs = x.
CHANGE?

n=current port.

for ports 1-2: x=NONE, AT, PAD,

PAD D, V25 BCS, V25 HDLC

for ports 3-4: x=NONE, AT, PAD,

PAD D, EIA-366
Pn: AT
OPTIONS?

Pn: STATUS DIS­PLAY x.
CHANGE?

n=current port

x=ON, OFF, ANS OFF

Pn:MSG
FORMAT= x.

CHANGE?

n=current port

x=VERBOSE, NUMERIC

Pn:RESULT
CODES OPT=x.
CHANGE?

n=current port

x= OFF, ON

Pn:CONNECT
MSGS = x.
CHANGE?

n=current port

x= BASIC, ALL, BUSY

Table 5-1. Menu Option Summary (Continued)

Main Level Level 1 Level 2 Level 3 Level 4 Description

Navigation button
directions:

YES NO HOME

UTA220/UTA220k 5-5

LCD Operation

CONFIGURA­TION OP­TIONS?

(cont.)

PORT CONFIG
OPTIONS? ?

(cont.)

Pn: DTE CMD
AND

MESSAGE
OPTIONS?

(cont.)

Pn: AT
OPTIONS?

(cont.)

Pn: ESCAPE
CHAR=x.
CHANGE?

n=current port

x= 0 - 127; 128-255 disabled

Pn:CR CHAR=x.
CHANGE?

n=current port

x= 0 - 127

Pn:LF CHAR=x.
CHANGE?

n=current port

x= 0 - 127

Pn:BS CHAR=x.
CHANGE?

n=current port

x= 0 - 127

Pn:GUARD
TIME=x.
CHANGE?

n=current port

x= 0 - 255
Pn: X.3 PARMS? Pn:SESSION = s.

CHANGE?

n=current port

s = 1 - 4

PnSsR1:PAD
RECAL CHAR=x.
CHANGE?

n=current port

s = current session

x= 000 - 126

PnSsR2:ECHO =x.
CHANGE?

n=current port

s = current session

x= ENABLE, DISABLE

PnSsR3: DATA
FWD CHAR = x.
CHANGE?

n=current port

s = current session

x= 0, 2, 126

PnSsR4:IDLE
TIME DELAY = x.
CHG?

n=current port

s = current session

x= 0-127

PnSsR5:ANCIL
DEV CTL= x.
CHANGE?

n=current port

s = current session

x =NONE, DATA, DATA CMD

PnSsR6:PAD
SERV SIG=x.
CHANGE?

n=current port

s = current session

x= SUPRESS, ALL-PRM,

PROMPT, ALL

PnSsR7:BRE AK
SIG ACT= x.
CHANGE?

n=current port

s = current session

x= 00 - 37

PnSsR8:
DISCARD = x.

CHANGE?

n=current port

s = current session

x= NORMAL, DISCARD

PnSsR9:PAD
AFTER CR=x.

CHANGE?

n=current port

s = current session

x= 000 - 255

PnSsR10:LINE
FOLDING=x.
CHG?

n=current port

s = current session

x= 000 - 255

PnSsR11:PAD
DTE SPEED=
x.CHG?

n=current port

s = current session

x= 300, 600, 1200, 24 00, 4800,

9600, 19200, 38400

PnSsR12:PAD
FLOW CTL=x.
CHG?

n=current port

s = current session

x= OFF, ON

PnSsR13:LF INS
AFTER CR=x.
CHG?

n=current port

s = current session

x= 0 - 7

Table 5-1. Menu Option Summary (Continued)

Main Level Level 1 Level 2 Level 3 Level 4 Description

Navigation button
directions:

YES NO HOME

5-6 UTA220/UTA220k

L

CD Operation

PnSsR14:PAD
AFTR LF=x.
CHANGE?

n=current port

s = current session

x= 000 - 255

PnSsR15:
EDITING=x.

CHANGE?

n=current port

s = current session

x= ENABLE, DISABLE

Table 5-1. Menu Option Summary (Continued)

Main Level Level 1 Level 2 Level 3 Level 4 Description

Navigation button
directions:

YES NO HOME

UTA220/UTA220k 5-7

LCD Operation

CONFIGURA­TION OP­TIONS?

(cont.)

PORT CONFIG
OPTIONS? ?

(cont.)

Pn: DTE CMD
AND

MESSAGE
OPTIONS?

(cont.)

Pn: X.3 PARMS?

(cont.)

PnSsR16:CHAR
DEL CHAR=x.
CHANGE?

n=current port

s = current session

x= 000 - 127

PnSsR17:LINE
DEL CHAR=x.
CHANGE?

n=current port

s = current session

x= 000 - 127

PnSsR18:LINE
DIS CHAR=x.
CHANGE?

n=current port

s = current session

x= 000 - 127

PnSsR19:EDIT
SRV SIG =x.CHG?

n=current port

s = current session

x= NONE, PRINTER, DISPLAY

PnSsR20:ECHO
MASK=x.
CHANGE?

n=current port

s = current session

x= 000 - 255

PnSsR21:PARITY
CHECK=x.
CHANGE?

n=current port

s = current session

x= YES, NO

PnSsR22:PAGE
WAIT = x.
CHANGE?

n=current port

s = current session

x= 000 -255

Pn:DTE PI N
OPTIONS?

Pn:DTR PIN
OPT= x.
CHANGE?

n=current port

x= IGNORE, RCAL ACU, HANG

UP, RELOAD, DIAL
Pn:DSR PIN

OPT= x.
CHANGE?

n=current port

x= ON, NORMAL
Pn:DCD PIN

OPT= x.
CHANGE?

n=current port

x= ON, NORMAL, DISC OFF
Pn:CTS PIN

OPT= x.
CHANGE?

n=current port

x= RTS, ON
Pn:DCD DROP

TIME=x.
CHANGE?

n=current port

x= 000 -255
Pn:DTR DE-

TECT TIME=x.
CHANGE?

n=current port

x= 000 -255
Pn:RTS TO CTS

TIME=x.
CHANGE?

n=current port

x= 000 -255

Pn: ISDN
PROTOCOL

OPTIONS?

Pn:PROTO­COL=a.
CHANGE?

n=current port

a = V.120, X.25, Clear, TLink,

Bond
Pn:RATE
MULTIPLR=a.

CHANGE?

n=current port

a = 1,2

Pn:FLOW CON­TROL

OPTIONS?

PN:x.FLOW CTL.
CHANGE?

n=current port

x= NO, UNI CTS, BI RTS/CTS,

BI XON/XOFF

Pn:RESET FLOW
CTL = x.
CHANGE?

n=current port

x= EN, DIS

Table 5-1. Menu Option Summary (Continued)

Main Level Level 1 Level 2 Level 3 Level 4 Description

Navigation button
directions:

YES NO HOME

5-8 UTA220/UTA220k

L

CD Operation

CONFIGURA­TION OP­TIONS?

(cont.)

PORT CONFIG
OPTIONS? ?

(cont.)

Pn: ISDN
PROTOCOL

OPTIONS?
(cont.)

Pn:V.120
OPTIONS?

Pn:MAX TX
FRAME SIZE=x.
CHANGE?

n=current port

x= 1-260

Pn:MAX RX
FRAME SIZE=x.
CHANGE?

n=current port

x= 1-260

Pn:WINDOW SIZE
= x. CHANGE?

n=current port

x= 1-127

Pn:T200 TIMER=
x.

CHANGE?

n=current port

x= 1-255

Pn:INFO FRM
SLCT=x.
CHANGE?

n=current port

x= I Frame, UI Frame
Pn:TLINK

OPTIONS?

Pn:x. CHANGE? n=current port

x= ADAPTIVE MODE, FIXED

MODE

Pn:DTR=x.
CHANGE?

n=current port

x= ASSERT, NORMAL

Pn: RTS=x.
CHANGE?

n=current port

x= ASSERT, NORMAL

Pn:SESSION
OPTIONS?

Pn:SESSION =s.
CHANGE?

n=current port

s = 1 - 4
PnSs:X.25
OPTIONS?

PnSs:RX
WINDOW SIZE=x.

CHANGE?

n=current port

s = current session

x= 0 - 8

PnSs:TX
WINDOW SIZE=x.

CHANGE?

n=current port

s = current session

x= 0 - 8

PnSs:RX
PKT SIZE=x.

CHANGE?

n=current port

s = current session

x= 0, 128, 256, 512, 1024

PnSs:TX
PKT SIZE = x.

CHANGE?

n=current port

s = current session

x= 0, 128, 256, 512, 1024

PnSs:PVC
OPTION=x.

CHANGE?

n=current port

s = current session

x= PVC, NON-PVC

PnSs: LOGICAL
CHN NUM=x.
CHANGE?

n=current port

s = current session

x= 000 - 255

PnSs:D BIT CONF
= x. CHANGE?

n=current port

s = current session

x= ON, OFF

PnSs:CUG
OPTION=x.

CHANGE?

n=current port

s = current session

x= NONE, BASIC, OUTGOING,

BILAT

PnSs:CUG
NAME=x.
CHANGE?

n=current port

s = current session

x= Closed User Group Name

PnSs:REVERS
CHRG OPT=x
CHANGE?

n=current port

s = current session

x= DIS, EN

Table 5-1. Menu Option Summary (Continued)

Main Level Level 1 Level 2 Level 3 Level 4 Description

Navigation button
directions:

YES NO HOME

UTA220/UTA220k 5-9

LCD Operation

CONFIGURA­TION OP­TIONS?

(cont.)

PORT CONFIG
OPTIONS? ?

(cont.)

Pn:SESSION
OPTIONS?

(cont.)

PnSs:X.25
OPTIONS?

(cont.)

PnSs:RX
THRUPUT=x

CHANGE?

n=current port

s = current session

x= 0, 75, 110, 300, 600, 1200,

2400, 4800, 9600, 19200,

48000, 64000

PnSs:TX
THRUPUT=x

CHANGE?

n=current port

s = current session

x= 0, 75, 110, 300, 600, 1200,

2400, 4800, 9600, 19200,

48000, 64000

x PnSs:NUI.
CHANGE?

n=current port

s = current session

x= NUI, up to 16 digits

x PnSs:RPOA.
CHANGE?

n=current port

s = current session

x= RPOA, up to 16 digits

Pn Ssx: USER
DAT.

CHANGE?

n=current port

s = current session

x= User Data, up to 12 digits

PnSs:TRANST
DELY=x.

CHANGE?

n=current port

s = current session

x= 00000-65535

PnSs:PKT
RST/CLR TMR=x.

CHANGE?

n=current port

s = current session

x= 000 - 600

PnSs:PKT
CALL TMR=x.

CHANGE?

n=current port

s = current session

x= 000 - 600

PnSs:AUTO
ACCEPT VC=x.

CHANGE?

n=current port

s = current session

x= EN, DIS

Pn:CALL
SETUP
OPTIONS?

Pn: ISDN
SPEED=x BPS.

CHANGE?

n=current port

x=64K, 56K

Pn: PERSIST DI­AL=x.

CHANGE?

n=current port

x=ENABLED, DISABLED

Pn:
ORIGINATE AS

x. CHANGE?

n=current port

x= DATA, AUDIO, SPEECH

Pn:ANS DATA x.
CHANGE?

n=current port

x= ENABLED, DISABLED
Pn:ANS

AUDIO x.
CHANGE?

n=current port

x= ENABLED, DISABLED
Pn:ANS

SPEECH x.
CHANGE?

n=current port

x= ENABLED, DISABLED
Pn:DIAL x

CHANGE?

n=current port

x=ENBLOC, OVERLAP
Pn:ECHO
DISABLE

TONE= x.
CHANGE?

n=current port

x= OFF, ON

Pn:WAIT FOR
CONN= x.
CHANGE?

n=current port

x= 0-255

Table 5-1. Menu Option Summary (Continued)

Main Level Level 1 Level 2 Level 3 Level 4 Description

Navigation button
directions:

YES NO HOME

5-10 UTA220/UTA220k

L

CD Operation

Pn: SAVE TO
NONVOL?

Pn:SAVE TO
NONVOL x.
CHANGE?

SAVING n=current port

x= 0, 1

CONFIGURA­TION OP­TIONS?

(cont.)

PORT CONFIG
OPTIONS? ?

(cont.)

Pn:PWR-UP
USER PROF = x.
CHANGE?

n=current port

x= 0, 1

CONFIG LOAD/
SAVE OP­TIONS?

LOAD/SAVE
SETUP?

SAVE
COMPLETE

SETUP TO NON­VOL?

SAVE SETUP
TO NONVOL x.
CHANGE?

SAVING x= 0, 1

LOAD ALL
PORTS FROM
NONVOL?

LOAD PORTS
FROM

NONVOL x.
CHANGE?

LOADING x= 0, 1

LOAD PORTS
FROM

FACTORY PRO­FILE?

LOAD
FACTORY

PROF x.
CHANGE?

LOADING x= 0, 1

LOAD/SAVE
PORT CONFIG
OPTIONS?

CURRENT
PORT=n
CHANGE?

n=1 - 2

Pn:SAVE PORT
TO NONVOL?

Pn:SAVE TO
NONVOL x.
CHANGE?

SAVING n=current port

x= 0, 1

Pn:LOAD PORT
FROM NONVOL?

Pn:LOAD FROM
NONVOL x.

CHANGE?

LOADING n= current port

x= 0, 1

Pn:LOAD FROM
FACTORY PRO­FILE?

Pn:LOAD FAC­TORY PROF x.
CHANGE?

LOADING n=current port

x= 0, 1

LOAD/SAVE
SWITCH

CONFIG OP­TIONS?

SAVE SWITCH
CFG TO

NONVOL?

SAVING

LOAD SWITCH
CFG FROM FAC­TORY?

LOADING

LOAD SWITCH
CFG FROM
NONVOL?

LOADING

DIAGNOSTIC
OPTIONS?

GLOBAL TEST? Note 5

Note 6

2B+D LOOP­BACK?

Note 7

TEST IN
PROGRESS s

GLOBAL TEST STATUS s =

2B+D LOOPBACK. Note 8

END TEST? TEST

COMPLETE

Table 5-1. Menu Option Summary (Continued)

Main Level Level 1 Level 2 Level 3 Level 4 Description

Navigation button
directions:

YES NO HOME

UTA220/UTA220k 5-11

LCD Operation

DIAGNOSTIC
OPTIONS?

(cont.)

PORT TEST? CURRENT PORT

= n. CHANGE?

Note 9

Pn: LOCAL
LOOPBACK?

Note 10

Pn: LOCAL TER­MINAL LOOP­BACK?

Note 10

Pn: DIGITAL
LOOPBACK?

Note 10

Pn:
BILATERAL

LOOPBACK?

Note 10

Pn:TEST IN
PROG s

n=current port

PORT TEST STATUS

s = LOCAL LOOPBACK, LOCAL

TERMINAL LOOPBK, DIGITAL

LOOPBACK, BILATERAL

LOOPBACK. Note 11

END TEST? TEST

COMPLETE

DISPLAY STA­TUS SOFT­LOAD?

SOFTLOAD s s = NOT INITIATED, IN

PROGRESS, COMPLETE,

FAILED

RESTART NET­WORK LINK?

RESETTING
LINK

The ISDN line is restarted using

the save switch setting

FRONT
PANEL
KEYPAD TEST?

KEYBOARD
TEST

* TO END

OR

HOME TO END

For numeric keypad:

* TO END displays.

For 3-button keypad:

HOME TO END displays.

Table 5-1. Menu Option Summary (Continued)

Main Level Level 1 Level 2 Level 3 Level 4 Description

Navigation button
directions:

YES NO HOME

5-12 UTA220/UTA220k

L

CD Operation

VIEW
PRODUCT
INFORMATION

b-s c p b = board number

s = software revision

c = checksum

p = PASS or FAIL

VIEW
DIAGNOSTIC
CODE?

DIAGNOSTIC
CODE =c.

c = diagnostic code value to aid

in field support.

CLEAR
DIAGNOSTIC
CODE VALUE?

CLEARING
DIAGNOSTIC
CODE

Resets di agnostic code value to

0.

Notes:

1. The next screen will be either the ENTER NUMBER TO DIAL? screen or the HANGUP? screen,
depending on the call status of the port. If the call status is IDLE, ENTER NUMBER TO DIAL?
is displayed; otherwise, HANGUP? is displayed.

2. The LCD advances to the call status screen.

3. VIEW/CHANGE STORED TEL NUM? screen is the last submenu un der DIAL/HANGUP OPTS.

4. Pressing YES or NO advances the LCD to the ENTER NUMBER TO DIAL? or the HANGUP?
screen (depending on the current status: IDLE: the LCD advances to DIAL?; otherwise the LCD
advances to HANGUP?).

5. Answering YES to DIAGNOSTIC OPTIONS? advances the LCD to the PORT TEST? screen if
a port test is in progress. Otherwise, the LCD advances to the GLOBAL TEST? screen.

6. Answering YES to GLOBAL TEST?, advances the LCD to the test status screen if a global test
is currently in progress. Otherwise, the LCD advances to 2B+D LOOPBACK?

7. Answering YES advances the LCD to the global test status screen.

8. Pressing YES or NO advances the LCD to the END TEST? screen.

9. Answering YES advances the LCD to the test status screen if a port test is currently in progress.
Otherwise, the LCD advances to the CURRENT PORT screen.

10. Answering YES advances the LCD to the global test status screen.

11. Pressing YES or NO advances the LCD to the END TEST? screen

Table 5-1. Menu Option Summary (Continued)

Main Level Level 1 Level 2 Level 3 Level 4 Description

Navigation button
directions:

YES NO HOME

UTA220/UTA220k 6-1

V.25 bis Dialer Operation

Chapter 6

V.25 bis Dialer Operation

V.25 bis is an autodial er option use d by synchronous DTEs to
perform dialing and UTA2 20 control funct ions. The UTA220
supports a subset of the CCITT V.25 bis recommendation,
primarily intended for the dialing and answering commands
for HDLC or BISYNC modes of V.25 bis operation.

SELECTING V.25bis

The V.25 bis option can only be sel ected using the LCD menu
or the AT@P1 command

To select V.25 bis wit h the LCD, s croll t hrough the menu and
select:

• CONFIGURATION OPTIONS?

• PORT CONFIG OPTIONS?

• DTE CMD AND MSG OPTIONS?

• DIALER CMDS = V.25 BSC for BISYNC mode or
DIALER CMDS = V.25 HDLC for HDLC mode

To select V.25 bis with the AT@P1 command, enter

• AT@P1 = VB for V.25 bis BISYNC mode or
AT@P1 = VH for V.25 bis HDLC mode.

The DTR pin is used to activat e the V.25 bis dial er. When t he
DTR pin goes high, the di aler command sett ing is used to s tart
the appropriate V.25 bis mode. When c hanging betwee n V.25
mode settings, drop and raise DTR to activate the new V.25
bis dialer mode.

You can select the speed of the dialer by changing the DTE
SPEED option. When you select V.25 bis di aler operation, the
DTE SPEED is used to configure the dialer port speed.

OPERATION IN V.25 bis MODE

When the V.25 bis option is enabled, most UTA220 options
still apply. Selecting V.25 bis forces the UTA220 into
synchronous communications mode (regardless of the
synchronous mode option). Only the DCD pin option setting
applies when V.25 bis is enabled and the UTA220 is off-line.

V.25 bis MESSAGE FRAMES

The CCITT V.25 bis recommendation describes several
message framing formats, including Async, BISYNC, and
HDLC (bit-oriented). The UTA220 supports the HDLC and
BISYNC modes. The ASCII (IA5) character set is used; the
EBCDIC character set is not supported.

6-2 UTA220/UTA220k

V.25 bis Dialer Operation

In HDLC operation mode, V.25 bis command and response
messages are contained in standard HDLC Unnumbered
Information (UI) frames (Figure 6-1). Each field consists of
one or more eight bit octets. The eight h bit ( pari ty bit) of each
octet in the Message field is ignored by the UTA220.

Figure 6-1. HDLC Frame for V.25 bis Messages

In BISYNC mode of operation, all V.25 bis commands and
response messages are contained in frames (Figure 6-2).

Figure 6-2. BISYNC Frame for V.25 bis Messages

The message field in the frame is composed of 7-bit IA5
characters with the eighth bit set for odd parity. If the HDLC
or BISYNC frames are improperly formatted, the frames are
ignored.

For more information on V.25 bis formatting and protocol
procedures, refer to the CCITT V.25 bis recommendation.

DTE INTERFACE PINS

The UTA220 supports V.35 and EIA-232 interfaces to the
DTE for V.25 bis dialing. The function of some pins on the
EIA-232 interface is different than in other synchronous
modes.

DTR Pin Operation

For the UTA220 to accept V.25 bis commands, t he DTE must
hold the DTR signal high. When configured for V.25 bis
dialing, the DTR pin option setting does not apply because the
V.25 bis specification explicitly defines how the dialer will
respond to changes in DTR.

DCD Pin Operation

The default operation of the V.25 bis dialer asserts the DCD
pin when DTR is high (DCD follows DTR). Some devices
may require DCD to be lo w until the connecti on is established.
For those devices, the UTA220 ca n be configured to only raise
DCD upon connection by setting the DCD pin option to
NORMAL. The DCD pin option setting of ON is the default
for CCITT V.25 bis operation.

UTA220/UTA220k 6-3

V.25 bis Dialer Operation

CTS Pin Operation

The UTA220 asserts the CTS pin when DTR is high (CTS
follows DTR), except that CTS goes low during the connect
sequence.

DSR Pin Operation

The UTA220 holds the DSR pin low until a connection is
established.

COMMAND PROCEDURES

When the UTA220 is in V.25 bi s command mode, it awaits th e
receipt of a V.25 bis command from the DTE. Each command
must be contained in a separate frame. The UTA220 also s ends
indications to the DTE to advise it of call status.

Commands may be upper or lower case. Responses and
indications from the UTA220 are always uppercase.
Commands cannot contain leading or embedded spaces or
other characters, but some commands allow c larity charact ers
in the parameter string that follows the command.

Each comm and message consists of a three octet command
code and a 0 to 60 octet parameter field (depending on the
command). The UTA220 parses the command, returns a
response message, and then executes the command.

COMMANDS

Commands are messages sent by the DTE to the UTA220 to
cause it to perform a given op eration. The commands are listed
on the following pages.

Dial Command: CRN xx..x

The CRN (Dial) command contains a parameter field of one
to 40 characters (excluding clarity characters) specifying the
number to dial and any dial modifiers. Clarity characters,
which are ignored by the UTA220, consi st of spa ces, dashes,
parenthesis, and periods. Valid dial characters and modifiers
are shown in Table 6-1.

Table 6-1: V.25 bis Dial Parameters

Character Function

0-9 Dial digits

* and # Dial digits

Space, dash,

parenthesis, and period

Clarity characters

6-4 UTA220/UTA220k

V.25 bis Dialer Operation

After dialing, the UTA220 att empts to establish a synchronous
connection with the remo te UTA220. As in other synchronous
modes, flow control and buffering are not used when V.25 bis
is enabled. When the call beg ins the connecti on sequence, the
UTA220 sends a Call Connect Indication (CNX) message.
Upon connection, the UTA220 r ai se s t he DSR p in and enters
the on-line data mode.

Examples of valid dial commands are:
CRN 12055550123

CRN 1 [phone]
CRN 9 1-205-555-0123

Responses to the dial command are:
VAL

INVCU
INVMS
INVPS
INVPV
CFI
CFIDT
CFIET
CFIRT
CFIAB

Refer to Table 2 for a descripti on of these respons e message s.

Connect Incoming Calls: CIC

This command forces the UTA220 t o answer an incoming cal l
if the port on which the call is received is configured for manual
answer (the auto-answer option is set to off). No parameters
are allowed. The DTE typically issues this command after
receiving an INC indication from the UTA220.

Responses to the CIC command are:
VAL

INV
INVMS
INVPS

INDICATION MESSAGES

Indication messages are unsolic ited messages sent by the
UTA220 to indicate a special co ndi ti on, such as an incoming
call. These messages are described below.

Call Connect Indication: CNX

The UTA220 sends this message to the DTE to indicate that
an incoming or outgoing call is physically connected end-to­end. The call connection sequence is then started. The DTE
should not begin sending data until the call connection
sequence is completed, which the UTA220 in dicates by raising
the DSR pin.

UTA220/UTA220k 6-5

V.25 bis Dialer Operation

Incoming Call Indication: INC

Upon receiving an inco ming call, the UTA220 sends the DTE
an Incoming Call Indication (INC). Only one indication is
given per call. If the auto-answer option is on, the UTA220
will answer the ca ll after the number of rings designated by th e
S0 command.

Response Messages

A response message is sent by the UTA220 immediat ely after
it receives a V.25 bi s command message . Respons e messages
are shown in Table 6-2.

Table 6-2: Response Messages

Character Function

VAL Valid Command.
INV Invalid Command. Command is invalid or inappropriat e.
INVCU Command Unknown. Transmission error (parity, framing)

occurred.

INVMS Invalid Message Syntax. Command is too long; command contains

invalid chara ct e rs .

INVPS Invalid Parameter Syntax. Wrong number of parameters;

parameter contains invalid character or too many characters.
INVPV Invalid Parameter Value. Parameter is out of range or is null.
CFIAB Call Failure, Call Aborted.
CFICB Call Failure, Local DCE busy.
CFIDT Call Failure, No Dial Tone.
CFIET Call Failure, Bu sy .
CFINT Call Failure, No Answer Tone.
CFIRT Call Failure, Connect Time-out.
CFI Call Failure, Reason Unknown.

6-6 UTA220/UTA220k

V.25 bis Dialer Operation

UTA220/UTA220k 7-1

EIA-366 Dialer Operation

Chapter 7

EIA-366 Dialer Operation

The UTA220 implements the EIA-366 dialer in accordance
with the EIA Standard RS-366 specification.

CONFIGURATION

The upper two ports of the UTA220 are configured as
EIA-366 dialer ports . In this confi guration, t he lower two p orts
function as the data ports for the dialer ports. The EI A-366 dialer
ports are dedicated to the data ports as follows:

• Dialer port 3 is dedicated to data port 1

• Dialer port 4 is dedicated to data port 2

OPERATION

Calls are initiated through the parallel dialer port interface (the
upper two ports).

The DTE connects to the dialer port by the DB-25 connector.
Connector functions are shown in Table 7-1.

Note: If an EIA-366A device is to be conn ected to a por t, ref er
to EIA-366A Requirements section in Appendix D.

Table 7-1: Dial Connector Functions

Pin Function

1 Frame Ground
2 Digit Present (DPR)
3 Abandon Call and Retry (ACR)
4 Call Request (CRQ)
5 Present Next Digit (PND)
6 Power Indication (PWI)
7 Signal Ground
13 Distant Station Connected (DSC)
14 Digit Lead 1 (NB1)
15 Digit Lead 2 (NB2)
16 Digit Lead 3 (NB4)
17 Digit Lead 4 (NB8)
22 Data Line Occupied (DLO)

7-2 UTA220/UTA220k

EIA-366 Dialer Operation

INTERFACE SIGNAL DEFINITIONS
Power Indication (PWI)

PWI is supplied by the di ale r to indicate the dia le r ha s power .

Call Request (CRQ)

CRQ is supplied by the DTE to req ues t t he di al er to initiate a
call. The on condition must be maintained during call
origination. If CRQ is tu rned off bef ore DSC is turned on, the
call is aborted. CRQ should not be turned on if DLO is on.
DLO indicates that the data por t is in us e and a call ca nnot be
initiated.

Data Line Occupied (DLO)

DLO is sent by the dialer to indicate when the data port is in
use. Off indicates the DTE can originate a call provided that
PWI is on.

Distant Station Connected (DSC)

DSC is supplied by the dialer to indicate that a call has been
completed and that t he dialer is no longe r in control of the data
port. Once the dialer has reli nquished co ntrol of t he data port,
DSC remains on until CRQ is turned off.

Digit Signal Circuits (NB1-NB8)

The DTE presents binary data to the dialer for dia ling or dialer
control purposes. Table 7-2 shows the dial digit character set
supported by the EIA-366A dialer.

Table 7-2: Dial Digit Character Set

Digit NB8 NB4 NB2 NB1

0 0000
1 0001
2 0010
3 0011
4 0100
5 0101
6 0110
7 0111
8 1000

UTA220/UTA220k 7-3

EIA-366 Dialer Operation

The telephone number can have up to 40 digits, including
special character s. If more than 40 digits are received, the dial er
turns on ACR and waits for CRQ to drop. The characters are
defined as follows:

* and #:

These are used for clarity only.

EON digit:

The EON digit is used when the line is
configured as a nailed-up line. The EON
digit signals that the end of the number has
been received. When it is received, DSC is
turned on. When configured for nail-up
line, it is not necessary to wait for the
connection before turning on DSC.

Other characters d ef ine d by EIA-366 are not s uppo rt ed by the
UTA220 dialer. Unsupported characters in a dial string are
ignored by the dialer.

Digit Present (DPR)

DPR is sent by the DTE to indicate to the dialer that the code
on the Digit Signal Circu its can be r ead. Circui t DPR must not
be turned on before Present Next Digi t (PND) comes on. When
DPR is on, it must remain on until PND goes off. When DPR
is off, it must be held off until PND comes on again. If DPR is
not turned on within five seconds after PND is turned on, the
dialer assumes it ha s received the last digit and dials any digit s
that have been received. If no digits have been received, the
dialer turns on Abandon Call and Retry (ACR) and waits for
Call Request (CRQ) to drop.

Present Next Digit (PND)

PND is turned on by the d i aler to ind icate that it is ready to
accept the next digit on the digit signal circuits NB1, NB2, NB4,
and NB8. Off indicates that the DTE shou ld turn off DPR and
set the states of NB1, NB2, NB4, and NB8 for the next digit.

9 1001

* 1010

# 1011

< (EON)1100

Table 7-2: Dial Digit Character Set (Continued)

Digit NB8 NB4 NB2 NB1

7-4 UTA220/UTA220k

EIA-366 Dialer Operation

Abandon Call and Retry (ACR)

ACR is supplied by the dialer to indicate that the call cannot
be successfully established. The on condition instructs the
DTE to abandon the call by dropping the call later. ACR
remains on until CRQ is turned off.

EXAMPLE DIAL SEQUENCE

The following is an example of the sequence of events that
occur when a call is initiated using the EIA-366A dialer port.

• Data Line Occupied (DL O) must be off for the dial sequence
to begin.

• The DTE turns on Call Request (CRQ) to initiate dialing.

• When CRQ is turned on, the dialer port turns on DLO to
indicate that the da ta po rt is now in use. The dialer turn s on
Present Next Digit (PND) to request a dial digit from the
DTE.

• The DTE sets the digit signal circuit bits (NB1, NB2, NB4,
and NB8) to the correct value for the first dial digit, then turns
on Digit Present (DPR).

• When DPR turns on, the dialer reads the digit and responds
with another PND.

• The PND/DPR sequence continues until either EON is
received or five seconds expires without receiving another
digit (DPR is not turned on to present another digit).

• When all the digits are received, the dialer initiates the call
on the data port to which the dialer is dedicated.

• When the call is connected, Distant St ation Connected (DSC)
is turned on by the dialer port. If the call cannot complete
successfully, Abandon Call and Retry (ACR) is turned on
until CRQ is turned off.

• The call can be terminated before the call is connected by
turning CRQ off.

• Once the call is completed, the call can be terminate d by
normal disconnect methods such as disconnect by the switch,
the front panel, or DTR disconnect.

UTA220/UTA220k 8-1

AT Command Operation

Chapter 8

AT Command Operation

This chapter provides information on how to use AT
commands to operate and configure the TA via a data port.

The UTA220 AT command set is shown in Appendix C.

AT COMMAND STATEMENT

The TA communicates with a DTE asynch ronously whenever
the corresponding DTE port is configured for AT command
mode. When the TA is powered up, any DTE p ort c onfigu red
for AT commands enters comma nd mode. AT commands can
then be used to configure and control the TA. The command
statement is typed using the DTE keyboard and temporarily
resides in a section of memory called a buffer.

The command statement must be written in a specific form so
the TA recognizes and f ollows t he in struc tion. Th e comma nd
statement begins with the letters AT and is f ollowed b y one or
more commands, which can each consist of a sequence of
keyboard symbols, such as & and %, letters, numbers, and is
followed by a return or end-of-line character.

AT Command Mode

AT commands can only be issued when the DTE port is
configured for AT command mode. Normally, the DTE port is
in AT command mode whenever it is off-line. After the TA
establishes a con nection with another TA and goes into on-line
data mode, characters se nt to the TA by the DTE are interpreted
as data (not as commands ) and are transmitted to the remote
TA.

If the DTE port is configured for DIALER CMDS = NONE,
AT commands are not accepted in any mode.

ESCAPE SEQUENCE: + + +

If the TA is in asynchronous data mode, the escape sequence
can be sent to re turn the TA to th e command mode an d remain
on-line. The escape sequ enc e cons is ts of a paus e (normally 1
second), three escape characters, an d then another pause. The
default escape sequence characters are: + + +.

The escape sequence characte r is set by the S2 command and
can be changed. The escape sequence can also be disabled to
prevent false escapes into command mode.

After entering the escape sequence, the TA returns to AT
command mode, but does not han g up or break the connec tion
with the remote TA. AT commands can now be entered to the
TA. The ATO command returns the TA to the data mode.

8-2 UTA220/UTA220k

A

T Command Operation

CREATING A COMMAND STATEMENT: AT

To create a command statement, use the following steps:

1. Type AT, the attention code telling the unit a command

statement follows.

2. Type the command.

3. Press the return key to “Enter” or send the command

statement to the TA.
An example of a command stat ement using the dial command

(D) follows.

ATD555-1212

This statement can be read as: Attention: dial 555-1212.
Another example: En ter ATZ. This means “Attentio n: reset the

TA and reload current configuration with stored values.”
After entering a command line the TA returns a response

message indicating whet her the command was accept ed, or by
giving the data requested by the command line.

The AT command also sets some of the TA’s DTE data
parameters, such as DTE sp eed , parity, and bits per character
to match the DTE. This process is repeated each time the AT
prefix is typed.

COMMAND STATEMENT GUIDELINES

When typing command s ta teme nts , t he following rules ap ply :

• Return must be pressed to execute (Enter) a command.

• The command buffer can hold 128 characters including
spaces.

• Use the backspace or delete key to erase the last character.

MONITOR DISPLAY

As commands are typed they normally appear on the DTE
monitor. This is called local character echo.

DTE CHARACTER ECHO: E

To determine if echo is set properly, ty pe AT. If the te rminal
displays AT, echo is set correctly. If it displays AATT, then
echo should be disabled by typing ATE. If the terminal does
not display the AT at all, echo should be enabled by typing
ATE1. The echo option only affe cts command mode operation.

COMMAND STATEMENT BUFFER

The TA temporarily stores up to 128 characters in a memory
buffer. If more th an 128 ch aracter s are ent ered befo re the end ­of-line charac ters, the TA ceases to e cho and waits for the end
of line character. To correct this condition, retype the com­mand using 128 characters or less.

UTA220/UTA220k 8-3

AT Command Operation

The charac ters the AT command interpreter u ses as end-o f­line, line feed, and backspace are set respectively by the S3,
S4, and S5 commands and can be changed.

The punctuation used i n tel ephone nu mbers ta kes up spa ce in
the buffer, as do blank characters used as spaces to help
increase readability.

BACKSPACE KEY

Use the backspace key to change the command statement or
correct errors. The backspace key allows the cursor to be
moved back to the charac ter(s) in error. The command can then
be retyped from that point.

Example: ATD5551211 ha s been typed . To change th e last 1
to 2, press the b ackspac e key o nce, t ype 2, a nd pres s ret urn t o
execute the command.

REPEATING A COMMAND: A/

This command tells the TA to repeat the last command stored
in its buffer. The command is automatically exe cuted without
any need to retype the command or press the return key.

Example: The ATD5551212 command h as been executed, and
the phone is busy. To r epeat the inst ruction type A/, but do not
use AT before this command, as AT would empty the buffer
and there would be no command to repeat.

NUMBERED COMMANDS

Series of commands starting with the same letter are
distinguished by a number following the letter.

For example, the E0 command selec ts echo off, and E1 selects
echo on.

GROUP COMMANDS

A group of commands can be typed in a single statement.
Pressing the RETURN key sends the entir e command string to
the TA, which execute s each command, in th e order it appe ars
in the command statement, from left to right.

For example, the command statement ATQ0V0D5551212
means:

• AT Attention

• Q Allow status messages to be sent

• V Select status

• D Dial 555-1212

The TA executes the AT command followed by the Q, V, and
D commands. The TA returns the status message
corresponding to the last command on the line. If an error is
encountered in a command line, subsequent comma nds on the
line are ignored.

8-4 UTA220/UTA220k

A

T Command Operation

Some commands use special formats or have special rules
concerning their use. For example, the dial D command
initiates the dial process so no other commands, only dial
modifiers, can follow the D command.

COMMAND SCOPE

The scope of a command refers to the extent of its effect on the
TA. AT commands have a scope of Global, Channel, or Port.

Global commands affect the operating characteristics of the
TA as a whole, potentially disrupting operation on all of the
ports and channels. Thus, a global command should be used
with caution (or no t at all) i f there are c urrently ac tive calls on
any port.

Channel commands affect only the operat ion of the B1, B2, or
D-Channels of the TA. These commands shou ld be used with
caution if there are active calls on any port.

Port commands affect onl y the operation of the particula r DTE
port in use. If the user i s issuing a port co mmand via DTE port
1, then only DTE port 1 charac teri stic s are af fect ed. This rule
does not apply if the user has entered Supervisor Command
Mode (explained in the next section).

Supervisor Command Mode

The UTA220 is equipped with a f eature called “AT Supervisor
Command Mode.” This allows AT c ommands issued from one
DTE port to be executed as if they were coming fr om another
DTE port. This includes call placement and call control.

To enter supervisor command mode, AT>Cn is en tered, where
n is the port to control. AT>C? can be entered to display which
port is being controlled. To return to control of the DTE port
to which you are connected, enter AT>C0 or AT>C.

For example, a user may be connected to DTE port 3 and want s
to control DTE port 1. The user enters AT>C1 at the DTE
console. Now the user may operate as if he or she were
connected to DTE port 1. All po rt commands issued from her e
on will affect DTE port 1 until the AT>C command is entered.

In supervisor command mode, when a call is placed for another
DTE port, the contro lled port enters the o n-line mode while the
superviso r port is still off-line. T he superv isory port s till has
full control of the control led DTE port. Connect messages are
directed to the supervisor port in addition to the port being
controlled.

Caution: There is no mechanism to prevent a DTE port from
being controlled by another DTE port. A DTE port can be
controlled by more than one other DTE port.

UTA220/UTA220k 9-1

Rate Adaption

Chapter 9

Rate Adaption

To allow greater fle xib ility for your DTE, thr ee r at e a dapt io n
protocols are available for use on the B-channel: T-Link,
V.120, and Bonding (see Chapter 10 for a description of
Bonding). These protocols allow your DTE to operate both
synchronously and asynchronously, and at a different speed
than the B-channel.

RATE ADAPTION

When a data call is placed, the TA tries to establish physical
data connection on the ISDN B-channel. The B-channel is a
digital channel that can transfer data at 56 or 64 kbps,
depending on the path the network chooses when routing the
call.

A rate adaption protocol is nece ssary if the user ’s DTE rate is
other than 56 or 64 kbps . The protoc ol adapts the lower s peed
of the DTE to the higher speed of the ISDN B-channel. The
LCD menu or the AT%A2 command can be used to select a
rate adaption protocol.

This chapter dis cusses two rate adaption pro tocols: TLink an d
V.120.

• T-Link does not guarantee error free dat a; it onl y adapt s the
lower DTE speed to the higher ISDN speed to a maximum
of 19.2 kbps asynchronous and 64 kbps synchronous.

• V.120 is an error-controlling protocol that guarantees error
free data transfer at speeds up to 128 kbps. (Throughput is
limited by the B-Channel to about 70 kbps.)

T-LINK

T-Link is a Northern Telecom proprietary rate adaption
protocol. It supports synchronous and asynchronous rate
adaption at a variety of speeds.

To select T-Link with the LCD, scroll through the menu and
select:

• CONFIGURATION OPTIONS?

• PORT CONFIG OPTIONS?

• PROTOCOL OPTIONS?

• PROTOCOL = T-LINK

To select T-Link with the AT%A2 command, enter
AT%A2=1.

9-2 UTA220/UTA220k

R

ate Adaption

When using a rate adaption protocol, both the calling and
called units must use the same protocol. Also, unless the TA

is configured for T-Link “adaptive mode,” the DTEs on both
ends must be set to the s ame DTE speed before d ata can be
transferred. In the adapti ve mode, t he TA can adj ust i ts spe ed
automatically to match the remote unit. To use this mode,
however, the DTE must also be able to change its speed
according to the co nnect speed of the TA, as i ndicated by the
rate in the connect message.

Flow Control and Pin Options

When using T-Link the flow control option for the DTE port
is overridden. In addi tion the RTS, CTS, and DTR pin options
are overridden. The T-Link protocol itself defines the way
these pins are handled.

T-Link transmits the state of the RTS pin to the remote TA
where it is transmi tted bac k as t he CTS state. DTR i s ma pped
to the remote end as DSR, bu t it is not looped back.

T-Link Options

Fixed/Adaptive:

• In fixed mode, the TA will not negotiate setup. If the other
TA is not set to the same speed the negotiation will fail.

• In adaptive mode, the called TA will be asked to adapt to the
originator’s parameters. If the called TA is set for fixed mode
and its parameters don' t match the originator’s, the called TA
will request that the originator adapt to it.

RTS Assert/Normal:

• In RTS assert mode, T-Link operates as if RTS is always
asserted

• In RTS normal mode, T-Lin k passes the state of the RTS pin
to the remote TA

DTR Assert/Normal:

• In DTR assert mode, T-Link operates as if DTR is always
asserted

• In DTR normal mode, T-Link passes the st ate of the DTR pin
to the remote TA

UTA220/UTA220k 9-3

Rate Adaption

V.120

V.120 is a CCITT protocol that supports synchronous and
asynchronous rate adaption, and al so provides link-layer er ror
control. Although er rors on a dig ital netw ork are rare r than on
an analog telepho ne line, t hey are p ossible. V.120 provides an
end-to-end protocol for detecting and correcting any such
errors. V.120 also performs buffering and can thus support
flow control to and from the DTE.

To select V.120 with the LCD, scroll through the menu and
select:

• CONFIGURATION OPTIONS?

• PORT CONFIG OPTIONS?

• PROTOCOL OPTIONS?

• PROTOCOL = V.120

To select V.120 with the AT%A2 command, en ter AT%A2=2.

V.120 Options

Maximum Transmit Frame Size is the max imum si ze a fr ame
can be for transmitting. The transmit frame size affects the
store-and-forward delay.

Maximum Receive Frame Size is the maximum size frame that
is accepted by the TA. L arger frames are rejected.

Window Size is the number of frames that can be sent before
an acknowledgment is received. This parameter is normally
not changed.

T200 Timer is the len gth of time to wait for ackn owledgment
of a sent frame. If this timer expires, V.120 attempts to send
the frame again.

9-4 UTA220/UTA220k

R

ate Adaption

UTA220/UTA220k 10-1

BONDING

Chapter 10

BONDING

BONDING is a new protocol standard from the Ban dwidth ON
Demand INteroperabilit y Group for combining the band width
of several 56 kbps or 64 k bps channels. BONDING can ‘bond ’
from 2 to 31 channels at once. The high speed d ata, which must
be a multiple of 56 kbps or 64 kbp s, is split aft er ar rival a t the
DTE interface into th e va ri ous channels. On the opposite end
the data is recomb ined into the origin al data stream and se nt to
the DTE interface.

BONDING ON THE UTA220

Because the UTA220 supports one ISDN basic rate interface
(2B+D), two simultaneous calls can be made, allowing an
effective bandwidth of 112 kbps or 128 kbps. The BONDING
call can be made from port 1 or port 2. Table 10-1 lists
BONDING call options.

Table 10-1: BONDING Options

Option Select

CONFIGURATION /
PORT /
PROTOCOL

Bond

CONFIGURATION /
PORT /
BONDING OPTIONS /
RATE MULTIPLR

Set to 2 in order to req uest a 112 kbps or 128 kbps call.
Set to 1 in order to re quest a 56 kbps or 64 kbps call .

Note: To run 56 kbps or 64 kbps, it is simpler to use
clear channel transfer (select PROTOCOL: NONE). If
you request a rate multiplier of one, it will negotiate
parameters according to the BONDING specifica tion
at the start of the call and then switch to a 56 kbps or
64 kbps clear channel call.

CONFIGURATION /
PORT /
BONDING OPTIONS /
SEC CALL PORT

This option is needed only for AT&T 5E5/5 E6 lines. If
configured for multiple cal l r eferences , set por t 1 to 1
and port 2 to 2. This will cause the second call to use
the same directory number as the f irst. If the line is not
configured for multiple call references and the BOND­ING call is being placed on port 1, set both port 1 and
port 2 to 2 (this is the default). If placing the BONDING
call on port 2, set both por t 1 and port 2 to 1. This will
cause both directory numbers to be used for the two
channel BONDING call.

10-2 UTA220/UTA220k

B

ONDING

PLACING A BONDING CALL

You can place a call from port 1 or port 2 using any normal
means. The answering part y must be set to ru n BONDING or
the call will disco nnect shortly after conne ction. If you specify
a rate multiplier of 2 and the a nswe ri ng party indicates it will
support 2 or more channel s for BONDING, the answering side
will pass the directory number for the second call in the
negotiation. The second call is made automatically. You can
tell this call is being made by the flashing LED on the second
B-channel. If delay equalization between the channels is
obtained, data mode is entered. The front panel indicates the
BONDING connection, the B-channel line speed (56 or 64
kbps), and the DTE speed (56, 64, 112, or 128 kbps). The
B-channel LEDs remain on when da ta mode has been entere d.

Note: When a rate multipl e of 2 is negotiated, both B-chan nels
are used. The remaining ports are prevented from making
circuit switched calls for the duration of the BONDING call.

If the rate multiple is set to 1 on either the originator or
answerer, the second call will not be made a nd data mode will
be entered immediately after negotiation. The second call will
not be made and d ata mode will be entered immedi at el y after
negotiation. The screen will indicate the speed the call
connected at.

The Directory Numbers c onfigured in the D-ch annel setup tell
the origination side what the second Directory Number is. If
you are using a point-to-point line with only one Directory
Number, on answering a BONDING call that is requesting two
channels, this dire ctory nu mber will b e sen t to th e or igina tion
side, which is t he same number as the firs t one dialed. This i s
because a point-to-point line can receive two calls using the
same Directory Number. AT&T 5E5/5E6 can also be
configured to receive two calls using the same Directory
Number. To use this capability, change port 1’s SEC CALL
PORT (located under BONDING OPTIONS in
CONFIGURATION / PORT) to 1 and set port 2’s SEC CALL
PORT to 2.

DISCONNECTING A BONDING CALL

Disconnecting by any normal means disconnects all
BONDING channels. If either channe l is di sconne cted b y the
switch, the entire call is disconnected by the UTA220. The
disconnection can be validated by the LCD screen indicating
DISCONNECTED and the B1 and B2 LEDs being off.

UTA220/UTA220k 11-1

Synchronous Operation

Chapter 11

Synchronous Operation

SYNCHRONOUS MODES

The UTA220 supports two synchronous modes. Operation in
each of these modes is described below.

Synchronous Mode 1: Sync Pause Mode

When a telephone con nection is made, the UTA2 20 delays f or 5

seconds (configurable with the S25 command ’0’) before
monitoring DTR.

This delay serves two purposes. If separate dialing and
communication terminals are used, this allows the terminal
operator to switch th e EIA-232 cable between the two. If separat e
dialing and communications software is being used on th e same
terminal, the delay allow s time for the dialing software to
complete and the c ommunications soft ware to initializ e and turn
DTR on.

After the UTA220 connects, the DSR, CD, and CTS pins will be
high. This can be used by the DTE as an indication that it can
begin sending synchronous data to the UTA220.

The UTA220 disconnects if it detects an on-to-off transition of
the DTR pin when &D0 i s not in effect, or it r eceives a disconnect
message from the switch. After a disconnect, the UTA220
returns to the off-li ne state. If the UTA220 i s set to auto answe r,
it will only answer when DTR is on or &D0 is in effect. If you
do not want the UTA220 to answer, DTR must remain low for
at least 8 seconds after the ringing ends.

Synchronous Mode 2: Dial Stored Number Mode

The UTA220 will automatically dial the telephone number
stored in directory entry number 0 when it detects and
off-to-on transition of the DTR pin.

Once the UTA220 connects, the DSR, CD, and CTS pins will be
high to indicate to the DTE that it can begi n sending synchronous
data.

The UTA220 disconnects upon detecti ng an on-to-off transition
of the DTR pin when &D0 is not in effect, or receiving a
disconnect message from the switch. After disconnecting, the
UTA220 hangs up and returns to the
off-line state.

If the UTA220 is set to auto answer, it will only answer when
DTR is on or &D0 is in effect. If you do not want the UTA220
to answer, DTR must remain low for at least 8 seco nds after t he
ringing ends. After that time, DTR going high will cause the
UTA220 to originate a call . If DTR goes high during the ringing
process, but before the required ring count is reached, the
UTA220 will not originate a call.

11-2 UTA220/UTA220k

Synchronous Operation

UTA220/UTA220k 12-1

D-Channel X.25

Chapter 12

D-Channel X.25

The TA provides the 1984 CCITT specified X.25 protocol for
the D-channel with a Packet Asse mbler/ Disassembl er (PAD)
interface for async hr onous data terminals. The X.25 pr otocol
supports the following X.25 parameters:

• Single channel operation

• Modulo 8

• Transmit packet size maximum of 256 byte

• Receive packet size maximum of 256 bytes

• Link level window size maximum of 7

• Packet level window size maximum of 7

FUNCTIONAL DESCRIPTION
X.25

X.25 is a synchronous error-correcting protocol for data
transmission over public and private networks. The X.25
protocol is subdivid ed into three layers: physical, data li nk, and
packet (or networ k). Each layer is responsib le for specific parts
of the data trans missio n, er ror c heckin g, an d error corr ect ing.
Data is transmitted in packets that contain additional
information to facilitate the error checking and correcting.

PAD

The PAD act s as an inter mediary between the local user's
asynchronous terminal and the X.25 proto col. PAD f uncti ons
are specified by CCITT X.3, X.28, and X.29
recommendations. These recommendations are as follows:

• X.3 defines 22 PAD parameters that govern how the PAD
operates. These parameters specify how and when the data
from the asynchronous DTE is forwar ded to the re mote host
(assembly ) and how the data from the remote host dis plays
to the asynchronous terminal (disassembly).

• X.28 defines the PAD command s a nd r esponses that perm it
communication with the X.25 protocol via an asynchronous
terminal.

• X.29 defines supervisory packets used for communication
between the local PAD and the remote host's PAD.

12-2 UTA220/UTA220k

D

-Channel X.25

ESTABLISHING AN X.25 SESSION

Before using the TA for X.25 communications on the
D-channel, the user must subscribe to the ISDN D-packet
service. If the user is subscribed to the D-packet service, a
connection is automatically established between the TA and
the ISDN packet handler when the TA is first powered up. This
is known as the D-channe l X.25 link co nnection. Once the TA
is connected to the ISDN pa cket handler, the X.25 PAD is used
to make an X.25 virtual connection to a specific remote host

or device. The connection is called “virtual” because it is not
a direct physi cal connection ; a transmiss ion path is c reated for
each call and held unti l communications are completed an d the
connection is disconnect ed .

The following explains how an X.25 virtual connection
(session) is established and disconnected, as well as some of
the activities performed during the X.25 session.

Initialize the PAD

When the TA is first powered up, the TA is in the AT command
mode. There are three AT commands tha t t he TA supports to
initialize the PAD:

ATDD

AT@P1 = P

AT@P1 = D

Once the PA D is initiali zed, the PAD prompt character *
displays and the PAD is in the PAD command mode.

ATDD Command

The ATDD command is valid for in itiali zing the PAD o nly
when the D-channel X.25 link is established. If the ATDD
command is entered when the D-channel X.25 link is not
established, the TA r esponds with ERROR a nd remains in the
AT command mode.

AT@P1=P or AT@P1=D Command

The AT@P1=P or AT@P1=D comman d initializes the PAD
automatically when the TA is powered up. If the D-channel
X.25 link is not established when the TA is powered up, the
PAD is initialized to the PAD command mo de. Likewise , if
the D-channel link is connected when the TA is powered up,
the PAD is initialized to th e PAD command mode, just as
though an ATDD had been executed.

UTA220/UTA220k 12-3

D-Channel X.25

Note: The AT@P1=P and AT@P1=D commands do not take
effect until the TA power is cyc led or the TA is restarted. The
AT&W command must be executed to save al l port parameters.

Establishing an X.25 Virtual Connection

There are three modes of operation for the PAD:

• Command mode

• Connect-in-progress mode

• Data transfer mode

Initially, the PAD is in the PAD co mmand mode where PAD
commands can be execut ed and an X.25 virtual connect ion can
be established if the D-channel X.25 link is connected.

An X.25 virtual call can be established by initiating the PAD
select command containing the desired requested facilities
and/or Network User Address (NUA).

Refer to the PAD COMMAND SET section for the rules
governing the format of the PAD select command. The
facilities permit the user to request special services from the
ISDN network at call-setup time. The NUA informs the ISDN
packet handler of the remote location address the user is
requesting for connection through the ISDN network.

Example: R-12345678
This command requests reverse charging and direct s the virtual

call to the NUA 12345678.
During establishment of the X.25 virtual call connection, the

PAD is in the connect-in-progress mode. When the virtual call
is established, the following message displays:

COM

The PAD is now in the data transfer mode and data excha nge
can begin.

Note: Data is transmitted through the PAD that is packeting
the data. Echo of PAD data and PAD commands is performed
locally by the PAD.

12-4 UTA220/UTA220k

D

-Channel X.25

Escaping to PAD Command Mode

When in data transfer mode or conn ect-in-progress mode, it is
possible to escape to the PAD command mode to execute a
PAD command. To escape to the PAD command mode issue
the PAD recall cha racter as s pecifie d by X.3 param eter 1. The
default PAD recall character for the TA is DLE (Ctrl P).

Once in the PAD command mode, the PAD pro mpt char acter
* displays and only one PAD command may be executed.
Upon execution of the PAD command, the PAD return s either
to the previous mode of the PAD (i.e., data transfer) or to the
final mode required by the execution of the PAD command
(i.e., after executio n of the PAD clear command, the final mode
is the PAD comma nd mode).

Escaping to AT Command Mode

To escape to the AT command mode from PAD data or
command mode, enter the AT escape command (+ + +) . This
temporarily suspends PAD operations an d follows st andard is
AT command function operat ion. To return to PAD operation
enter:

ATDD

To end the call and exit the PAD enter:

ATH

To save the port and current session configuration, including
the current PAD parameter configuration, to nonvolatile
memory enter:

AT&W

Disconnecting the X.25 Virtual Connection

The X.25 virtual call co nnection is disconnected by is suing the
PAD Clear command while in the PAD command mode.

Example: *CLR
This disconnects the vi rtual call but leaves the terminal ad apter

on-line and in the PAD command mode.
When the virtual call is disconnected, the PAD Clear

Confirmed response and PAD prompt chara cter are displayed :

CLR CONF

*

The PAD is now in the PAD command mode where another
X.25 virtual connecti on can be establis hed via the PAD Select
command.

UTA220/UTA220k 12-5

D-Channel X.25

COMMON APPARENT PROBLEMS

During a session the X.25 network or remote PAD can alter
the current valu es of t he X.3 para mete rs re sul ting i n com mon
apparent problems.

Parameter 1 Changed

PAD recall using the character DLE (Ctrl P) is no longer
possible.

Parameter 2 Changed

Characters are no longer echoed when in the PAD command
mode.

Parameter 5 Changed

Flow control charac ters are sent to the DTE by the PAD dur ing
the PAD command mode.

Parameter 6 Changed

The PAD prompt no longer appears when in the PAD
command mode.

Parameter 20 Changed

Editing characters are echoed.

PAD COMMAND SET

The X.25 PAD serves as an asynchronous interface through
which the X.25 protocol and PAD operation can be control led.
PAD commands are specified in X.28 by CCITT which allow
for communication directly with the PAD. Some of the X.28
PAD commands control the X.25 protocol operation such as
call setup, call clearing, etc. The rest of the PAD commands
provide access to th e X.3 PAD paramet ers for PAD operatio n
control (refer to the X.3 Parameters and Values section).

PAD Command Format

The format of each PAD command is describe d in the sec tion
below. The PAD accept s either upper or lowerc ase ch aracters
for the PAD command characters. Any spaces inserted in the
PAD command are ignored except for spaces in the call us er
data of the PAD select command (see PAD sel ect command).
A PAD command line can contain up to 128 characters.
Multiple PAD commands are not permitted on a command
line.

12-6 UTA220/UTA220k

D

-Channel X.25

Issuing PAD Commands

PAD commands are accepted by the PAD only when it is in
PAD command mode (when a PAD prompt character *
displays at the beginning of the command line). As eac h PAD
command character is typed, the character i s echoed to the local
DTE device for display, unless echoing is disabled by X.3
parameter 2.

Each PAD command is input to the PAD by typing the PAD
command delimiter c haracter (a carriage return or + character )
at the end of the command line. The PAD commands can be
edited, unless ed iting is disabled by X.3 par ameter 15, any time
before the command is input to the PAD. Once the PAD has
executed the command, a response, called a PAD service
signal, is returned to the DTE to inform the user of the result
of the command execution.

Note: An incorrect PAD format will cause an ERR response.

Status: STAT

This command requests t he virtual call st atus of the local DTE.
Response:
ENGAGED - Indicates the local DTE is currently engaged in

a virtual call.
FREE - Indicates the local DTE is not engaged in a virtual call.

Clear: CLR

The clear command disconnects the virtual call connection.
Response:
CLR CONF - Confirms that the clear comman d was accepted

by the packet handler and the current virtual call was
disconnected.

CLR ERR - Indicates that the clear command was in error
because a virtual call was not established, or that the PAD is
in an unknown mode and cannot accept the clear command.

CLR DER - Indicates that the remote end is no longer
responding because no response to the clear or additional
retransmission of the clear was received.

RESET

This command resets the current virtual call. When resetting
the call, the packet sequence counters P(r) and P(s) and the
packet window are res et to 0. Outstanding da ta or data stored
from the local DTE i s disc arded. The reset retu rns the c urrent
virtual call to a known mode (the same mode the virtual call
was in when it was first established). This command is only
valid when a virtual call is connected.

UTA220/UTA220k 12-7

D-Channel X.25

Note: The CR LF characters indicate a carriage return and
line feed response and are not actually displayed.

Response:

CR LF - Indicates the reset of the virtual call is complete.
ERR - Indicates a reset command error caused by either a

virtual call not bei ng e st abl ished or the PAD being in a mode
unknown to the user.

Interrupt: INT

This command initiates the transmission of an interrupt packet
to the remote DTE. This command i s only valid when a call is
connected.

Response:

CR LF - Indicates that the interrupt packet was transmitted.
ERR - Indicates an interrupt command error caused by a

virtual call not bei ng e st abl ished or the PAD being in a mode
unknown to the user.

SET

This command sets or changes the value of one or more X.3
parameters.

A colon must be placed between the parameter and its
corresponding value. I f more t han one paramet er is re ques ted
to be set or changed, a comma must delimit the value an d the
next parameter.

SET <parameter>:<value>,<parameter>:

<value>,...

Note: Refer to Table 6 for a list of X.3 parameters and their
corresponding default values.

Response:
CR LF - Indicates that the parameter specified in the set

command is set to its corresponding specified value.
PAR <parameter>: INV - Indicates that the specified

parameter is incorrect or cannot be changed because it is a
READ ONLY parameter (i.e., parameter 11 is a READ ONLY
parameter), or the value specified in the set command is an
invalid value for the specified parameter.

12-8 UTA220/UTA220k

D

-Channel X.25

Read: PAR?

This command requests a display of the current values of the
specified X.3 parameter(s).

If more than one parameter is specified, each must be delimited
by a comma. If none are specif ied, all p aramet ers ( 1 - 2 2) and
their corresponding values are displayed.

PAR? <parameter>,<parameter>,...

or

PAR?

Response:
PAR <parameter>:<value>,<parameter>: <value>, ... -

Lists each parameter specified by the read command and the
corresponding value.

PAR <parameter>: INV - Indicates the invalid parameter
specified in the read command.

Set and Read: SET?

These commands request th e setting or changing of the current
values of the spec if ied X.3 parameters an d di spl ay the values
after the setting or changin g.

A colon must be placed between the specified parameter and
its correspond ing s pecif ied valu e. If more t han one par ameter
is requested to be set or changed, a comma must delimit the
value and the next parameter reference.

SET? <parameter>:<value>, <parameter>:

<value,.>...

Response:
PAR <parameter>: <value>, <parameter>: <value>... -

Lists each parameter specified by the set and read command
and the corresponding value.

PAR <parameter>: INV - Indicates the specified paramete r
is incorrect or cannot be ch anged because it is a READ ONLY
parameter, or the va lue speci fied in the s et and read co mmand
is an invalid value for the specified pa rameter.

Remote Read: RPAR?

The read command r equest s a dis play of the c urrent val ues of
the specified X.3 parameter(s) from the remote PAD. This is
only valid if an X.25 call is active.

If more than one parameter is specified, each must be delimited
by a comma (,). If none are specifi ed, all parameters (1-22) and
their corresponding values are displayed.

UTA220/UTA220k 12-9

D-Channel X.25

RPAR? <parameter>,<parameter>,...
or
RPAR?
Response:
PAR <parameter>:<value>,<parameter>:<value>,... - Lists

each parameter specified by the read command and the
corresponding value.

PAR <parameter>: INV - Indicates the invalid parameter
specified in the read command.

Remote Set and Read: RSET?

These commands request, from a remote PAD, the setting or
changing of the cu rrent values of the specifie d X.3 parameters
and display the values after the setting or changing from the
remote PAD. This is only valid if an X.25 call is active.

A colon must be placed between the specified parameter and
its correspond ing s pecif ied valu e. If more t han one par ameter
is requested to be set or changed, a comma must delimit the
value and the next parameter reference.

RSET? <parameter>:<value>,

<parameter>:<value>,...

Response:
PAR <parameter>:<value>,<parameter>:<value>,...-- Lists

each parameter specif ied by the set and rea d command and the
corresponding value.

PAR <parameter>: INV--Indicates the specified parameter
is incorrect or cannot be ch anged because it is a READ ONLY
parameter (i.e., parameter 11 is a READ ONLY parameter), or
the value specified in the set and read command is an invalid
value for the specified parameter.

Profile Read/Save: PROF

These commands allow the user to load a saved, default, or
standard set of X.3 parameters from non-volatile memory or
save the X.3 parameters to one of two user profiles in
non-volatile memory. The PROF command syntax is as
follows:

PROF 90, PROF SIM: Will load the CCITT simple standard
profile.

PROF 91, PROF TRA: Will load the CCITT transparent
standard profile.

PROF NVM #(0,1): Will load from one of two specified
non-volatile memories a profile stored by the user.

PROF SAV #(0,1): Will store the curr ent X.3 profile i nto one
of two non-volatile memories as specified.

PROF DEF: Will load the factory default X.3 profile.

12-10 UTA220/UTA220k

D

-Channel X.25

PAD Select

This command establishes an X.25 virtual call connection
through the ISDN packet handler to a remote host or device.
The contents of the PAD select command determine the
contents of the X.25 Call Request packet. The format can be
in any of following three forms:

<facility request block> - <address b lock> <call

user data>

<facility request block> - <call user data>

<address block> <call user data>

The facility request block permits the user to request special
services from the ISDN network. If more than one facility is
specified, a comma must s eparate each faci lity. The end of the
facility request block must be followed by the hyphen
character.

The address block sp ecifi es th e c alled Net work Use r Addr ess
(NUA). The address cannot exceed 15 characters in length.
Abbreviated or multiple addresses are not supported.

The call user data fi el d cannot exceed 12 char act er s i n le ngt h
(including spaces) and must be preceded by either the P or D
character. Carriage returns and the + character are not
considered part of t he us er data field because they are treated
as PAD command delimiters.

Response:

COM - Indicates the virtual call is established.
ERR - Indicates the PAD is in an unknown mode that cannot

allow the PAD select command, th e PAD has been initial ized
in the off-line mode (i.e., no virtual call connection has been
established), or the PAD select command is invalid due to a
format error. Some PAD select format err ors are as follows:

• The facilities block is not followed by the - character.

• The CUG facility is requeste d and two decimal digits are not
specified.

• The RPOA facility is requested and four decimal digits are
not specified.

• The address block length exceeded 15 characters.

• The call user data block is not preceded by the P or D
character.

• The call user data block length exceeded 12 characters.

• An invalid fa cility is requested as the first facility in the
facility request block.

CLR xxx - Indicates t he attempted call has cleared. The xxx
is the ASCII character cause code which specifies the reason
the call attempt cleared (see PAD Clear Service Signals).

UTA220/UTA220k 12-11

D-Channel X.25

FACILITIES

The following facilities and corresponding code formats are
supported by the TA.

Reverse Charging: R

Reverse Charging is a facility analogous to “col lect” calls . All
connect charges are charged to the remote DTE. This facility
works in conjunction with the Reverse Charging Acceptance
facility. If the remote DTE does not subscribe to Reverse
Charging Acceptance, the local DTE's call with the reverse
charging request is cleared.

Format: R

Network User Identification (NUI)

This facility provides a way for the user to be identified by the
network for the purpose of billing, security, or network
management.

Format: N <NUI string>
A character string of up to 16 decimal characters from 33 to

126 of the ASCII character table (see Appendi x F) except for
characters 43 to 45 (hyphen, comma, and plus sign). Spaces
can be included in the specification of the NUI string but are
discarded by the PAD.

Echo to the local DTE is turned off upon ent er in g the N unti l
a comma or hyphen is entered. The comma signifies the end
of the NUI string and indicates that more facilities are to
follow. The hyphen signifies the ending of the facility block.
The P or D designator used for th e beginning of the user dat a
call does not end th e NUI string because it is cons idered a valid
NUI string character.

Closed User Group (CUG)

The Closed User Group (CUG) facility permits users to
essentially esta blish a private network on a publi c networ k by
restricting communications to only those who are designated
to be in the group. Access by anyone outside the group is
denied. The CUG number is assigned by the net work provider
at subscription time.

Format: G <xx>
<xx>: two dec imal digits ranging f rom 00 - 99. If two d ecimal

digits are not specified, the response ERR displays.

12-12 UTA220/UTA220k

D

-Channel X.25

Recognized Private Operating Agency

The Recognized Private Operating Agency (RPOA) facility
permits the user to specify the particula r international ga teway
to be used when initiating an international virtual call.

Format: T <xxxx>
<xxxx>: four decimal digits
If four decimal digits are not specified, the response ERR

displays.

Flow Control Parameter Negotiation

This facility permi ts the neg otiation on a per-call basis of the
packet and window sizes (flow control parameters) for each
direction of transmission. The packet size designates the
maximum data field length of the data packets. The window
size designates the number of data packets that may be sent
before acknowledgment of the received packets (i.e.,
permission to transmit more data packets) is received. Window
sizes do not have to be the same at both ends of the virtual
connection.

The TA cannot initiate negotiation of this facility, but will
respond to negotiati on fro m the net wor k. The pac ket win dow
size is changed by using the AT command !X0 (receive
window size), !X1 (transmit window s iz e) for th e D-Cha nnel
or %D0 (receive window size), %D1 (transmit size) for an
X.25 configured port (see AT commands).

If the window size is not the defaul t value of two, th e specified
window size value is re quested in the call r equest packet when
the virtual call is being established. The default packet size
supported by the TA is 128 bytes and can be changed using the
AT commands !X2 (receive pac ket size), !X3 (transmit packet
size), for the D-Channel or %D2 (receive packet size), %D3
(transmit packet size) for an X.25 configured port.

To allow maximum flexibility, the user may configure various
parameters, such as packet size, window size, call type/LCN
ranges, and packet modulus, for the D-Channel, Port, or
Session (session not yet implemented) differently for each
X.25 call.

The rules to determine the parameters used areas follows:

• If a session parameter (window or packet) is non-zero, the
session parameter is used.

• If the session p arameter is zero and the port parameter is
non-zero, the port parameter is used.

• If the session an d port parameters are zero, the D-Channel
parameter is used.

UTA220/UTA220k 12-13

D-Channel X.25

*Acknowledgment PAD service signal is transmitted to the local DTE as a carriag e return and a
line feed.

Table 12-1: PAD Command Set Summary

Command Description Response

STAT Requests virtual call status of

the DTE

ENGAGED or FREE

CLR Disconnects the current virtual

call

CLR CONF, CLR ERR, or CLR
DER

RESET Resets the current virtual call Acknowledgment PAD service

signal or ERR *

INT Transmits an interrupt packet Acknowledgment PAD service

signal or ERR *

SET Sets or changes the value of

one or more of the current
parameters

Acknowledgment PAD service
signal or ERR or PAR (list of
specified parameters and INV)
*

PAR? Requests display of the current

values of the specified
parameters

PAR (list of specified
parameters with their current
values or INV)

SET? Requests the setting or

changing of the current values
of the specified parameters
and display the values after the
setting or changing

PAR (list of specified
parameters with their current
values or INV) or ERR

RPAR? Requests the display from the

remote PAD of the current
values of the specified
parameters

PAR (list of specified
parameters with their current
values or INV)

RSET? Requests the setting or

changing from the remote PAD
of the current values of the
specified parameters and
displays the values after the
setting or changing

PAR (list of specified
parameters with their current
values or INV) or ERR

PROF Loads or St ores the current X.3

profile

Acknowledgment PAD service
signal or ERR*

PAD Select

Command

Sets up and establishes a
virtual call

COMM, ERR, or CLR xxx (see
PAD Clear Service Signals)

12-14 UTA220/UTA220k

D

-Channel X.25

PAD SERVICE SIGNALS

The local DTE may receive service signals from the PAD in
response to an is sued PAD command or as the res ult of a packet
or network action. Table 12-2 shows the service signals that
may be transm itted to the local DTE by the PAD.

Table 12-2: PAD Service Signals

Command Extension Reason

* PAD is in the PAD command state and the

user can issue a PAD command

ENGAGED Response to PAD STATus command

FREE Response to PAD STATus command

PAR Parameter:

value or
Parameter: INV

Response to set PAD command if one of the
parameters to be set is i nvalid or response to
set and read command or read command

ERR PAD command is in error

RESET See PAD Reset

Service Signals

Resetting by the network or remote DTE

CLR See PAD Clear

Service Signals

Clearing by the network or remote DTE

CLR CONF Confirmation of clearing either init iated by the

CLR PAD command or by the packet

CLR DER Restart on the network link or response to

packet virtual call request when the call
cannot be established

COM Call connected in response to a PAD Select

command or the receipt of an incoming call
(connection based upon acceptance of
incoming call by the packet)

XXX Line delete function performed for a printing

terminal

\ Character delete function performed for a

printing terminal

BS SP

BS

Character delete function performed for a
display terminal

CR LF Acknowledgment of a PAD command such

as RESET or INT

UTA220/UTA220k 12-15

D-Channel X.25

PAD Reset Service Signals

A reset service signal is transmitted to the local DTE when
resetting is init iated by th e network or remote DTE. The reset
cause code issued with the reset request packet from the
network or local DTE indicates the reason. The reset cause
code is inte rpreted by the PAD and t he resultan t cause code
service signal extension is transmitted to the local DTE with
the RESET service signal. The following is a list of the possible
reset service signals that may be transmitted to the local DTE
by the PAD.

Pad Clear Service Signals

A clear service signal is transmitted to the local DTE when
clearing is init iated by the network or remote DTE. The clear
cause code issued with the clear request packet from the
network or local DTE indicates the reaso n for the clearing. The
clear cause code is interpreted by the PAD and the resultant
cause code service signal extens ion is tr ansmitt ed t o the l ocal
DTE with the CLR service signal . Table 12-4 sho ws the clear
service signals that may be tr ansmitted to the l ocal DTE by the
PAD.

Table 12-3: PAD Reset Service Signals

Service

Signal

Reason

RESET DTE Reset by remote DTE

RESET

ERR

Reset due to a local procedure error

RESET NC Reset due to network congestion

RESET RPE Reset due to a remote DTE procedure

Table 12-4: PAD Clear Service Signals

Service

Signal

Reason

CLR OCC DTE is engaged in another cal l and c annot accept the i ncoming

call

CLR NC Network problem exists which prevents the network from

handling the call

CLR INV DTE requested an invalid facility

CLR NA DTE to DTE connection not allowed. For example, if the closed

user group was not the same the connect ion would not be allowed

CLR ERR Clearing error caused by the local DTE detected by the PAD

12-16 UTA220/UTA220k

D

-Channel X.25

X.3 PARAMETERS AND VALUES

Just as the AT commands control some of the operating

features of the TA, the X.3 parameters control the PAD’s
operating features . These parameters are user configurabl e and
remote configurable: the remote device can change the local
PAD parameters to designate how the PAD handles the data.

Most X.3 parameters gover n how the data displays be cause the
data display depends on the type of l ocal DTE or ap plica tion.
Other X.3 parameters govern PAD functions such as data
forwarding (when to stop packeting the data r eceived from the
local DTE device and transmit the packet), editing, flow
control, and service signal control.

Saving the X.3 Parameter Configuration

When the TA is first powere d up, the X.3 parameters are set
to the default (factory) settings (Table 12-5) . PAD paramete rs
can be modified usin g the set o r set and read PAD commands.
The PAD must be in the PAD command mode before the set
or set and read commands can be executed. During a virtual
call, the remote device can change the X.3 pa rameter
configuration from the user's set configuration. To avoid the
problems this may cause, the PAD saves the current settings
of the X.3 paramete rs to RAM an X.25 virtual c all is init iated.
When the virtual call is disconnected, the saved X.3 parameter
settings are restored. The PAD does not save the current X.3
parameter settings when the virtual call connection is
established by the remote DTE.

CLR RPE Remote DTE procedure error detected by the remote DTE/DCE

interface

CLR NP Called DTE address not assigned to any DTE
CLR DER Called number out of order or not responding
CLR DTE Remote DTE cleared the call
CLR RNA Called DTE not subscribed to reverse charging acceptance,

allowing the called DTE to accept the calling DTE’s request for
reverse charging (the reverse charge facilit y in the facility request
field of the call request packet)

Table 12-4: PAD Clear Service Signals (Continued)

UTA220/UTA220k 12-17

D-Channel X.25

Table 12-5: Default X.3 Parameters

Parameter Description Default Remarks

1 PAD recall using a

character

1 DLE character (Ctrl P) is the

PAD recall character
2 Echo 1 Enabled
3 Data forwarding

character selection

2 Carriage return character

(0Dh) is the data forwarding

character
4 Idle timer delay

selection

0 Timer = 0 secs

5 Ancillary device

control

2 Flow co n t rol o f loc a l DTE

device by PAD allowed in data

transfer
6 Control of PAD

service and
command signals

5 Transmit PAD command and

service signals in standard

form
7 Action of PAD on

break from DTE

0Do Nothing

8 Discard output 0 Normal data delivery
9 Padding after

carriage return

0 No padding after carriage

return

10 Line folding 0 No line folding
11 Binary speed of

DTE

- Set by current baud rate

12 Flow control of

PAD by DTE

1 DTE flow control of PAD

allowed

13 Line feed insertion

after carriage
return

5 Insert line feed after carriage

return transmitted to the DTE

and after echo of carriage

returns

14 Padding after line

feed

0 No padding

15 Editing 1 Editing is allowed during data

transfer

16 Character delete 8 Ctrl H (08H of ASCII Character

Table) is the delete character

17 Line delete 24 Ctrl X (18H of ASCII Character

Table) is the line delete

character

12-18 UTA220/UTA220k

D

-Channel X.25

To save the current X.3 paramet er configuration to nonvolatile
memory, escape to command mode and enter AT&W
(see Escaping to AT Command Mod e in Establishi ng an X.25
Session). Entering AT&W saves the port and current session
configuration as well as the X.3 parameters. The factory X.3
configuration can be restored by entering AT&F. This
command also restores port an d current sessio n configu ration.

CCITT specifies two standard profile s for the X.3 parameter
set. The transparent profile is recommended for applications
such as file transfers. The transparent profile essentially
disables most of the PAD features so that the file can be
transferred completely unaltered (no padding, line feed
insertion, flow control characters, or service signal messages
when transmitted to the DTE). The simple profile is an
alternative co nfiguration t o the TA’ s default configurati on for
simple interactive terminal applications. Table 12-6 lists the
X.3 parameters and the values supported by the TA.

18 Line display 18 Ctrl R (12H of ASCII Character

Table) is the line display

character

19 Editing PAD

service signals

2 Editing PAD service signals is

generated for display terminal s

20 Echo mask 64 No echo of edit characters
21 Parity treatment 0 No parity check or generation
22 Page wait 0 Disabled

Table 12-6: CCITT X.3 Parameter Profiles

Parameter Description Transparent

Profile

Simple

Profile

1 PAD recall using a character 0 1
2Echo 0 1
3 Data forwarding character selection 0 126
4 Idle timer delay selection 1 0
5 Ancillary device control 0 1
6 Control of PAD service and command

signals

01

7 Action of PAD on break from DTE 0 0
8 Discard output 0 0
9 Padding after carriage return 0 0

Table 12-5: Default X.3 Parameters (Continued)

UTA220/UTA220k 12-19

D-Channel X.25

Parameter 1: Pad Recall Character

This parameter designat es the PAD recall character. PAD
recall allows for escape from the PAD data transfer mode or
connect-in-progres s mode to the PAD command mode in order
to execute a PAD command. Only o ne PAD command can b e
executed after the PAD has escaped to the PAD command
mode. Once executed, the PAD returns to the previous mode
(i.e., data transfer or connect in progress). If parameter 5 is set
to 1, when PAD recall is executed, the PAD will output an
XOFF before displaying the PAD prompt.

* default

10 Line folding 0 0
11 Binary speed of DTE - ­12 Flow control of PAD by DTE 0 1
13 Line feed insertion after carriage re-

turn

00

14 Padding after line feed 0 0
15 Editing 0 0
16 Character delete 127 127
17 Line delete 24 24
18 Line display 18 18
19 Editing PAD service signals 1 1
20 Echo mask 0 0

Table 12-7: PAD Recall Character

Value Description

0 No character will result in PAD recall in either the data transfer or

connect-in-progress mode

1 PAD recall character = DLE. The charact er DLE (10H) c an be us ed

for PAD recall. (DLE = Ctrl P) *

Table 12-6: CCITT X.3 Parameter Profiles (Continued)

12-20 UTA220/UTA220k

D

-Channel X.25

Parameter 2: Echo

This parameter establishes whether or not characters
transmitte d from the local DTE device to the P AD is echoed
back to the local DTE dev ice by the PAD. For example , if echo
is enabled and the letter P is typed, the PAD transmits the
letter P back to the terminal.

default

Parameter 3: Selection of Data Forwarding Characters

Characters received from the local DTE device are stored by
the PAD until the data forwarding character is received , or
some other data forwarding condition has occurred. Parameter
3 designates the character or set of characters used to initiate
the forwarding of the data stored by the P AD. Be fo re the data
forwarding character is transmitted to the PAD, the data stored
by the PAD can be edited if parameter 15 is enabled.

Other conditions that cau se the PAD to auto matica lly forw ard
the data stored by the PAD are as follows:

• If editing is disabled (par ameter 15 = 0) and the PAD receives
enough data to fill a packet, one full packet is forwarded.

• If editing is enabled (parameter 15 = 1) and the PAD receives
enough data to fill the PAD edit ing buffer, the PAD forwards
one full packet.

• If the maximum assembly timer expi res before any other data
forwarding conditi ons occur, the data cur rently stor ed by the
PAD is forwarded. The maximum assembly timer is started
on receipt of the first character being packeted by the PAD
from the DTE and expires after 15 minutes.

• If editing is disabled (parameter 15 = 0) and the idle timer
delay expires (as set by para meter 4), the data currently stored
by the PAD is forwarded.

• If the PAD receives a break and the action to be performed
upon receipt of a br eak is no thing (pa rameter 7 = 0), t he data
currently stored by the PAD is forwarded.

• If the PAD receives the first character of a PAD command
signal after escaping from the data transfer mode, the data
currently stored by the PAD is forwarded.

• If the PAD receives a set, read, or set and read PAD messag e
from the remote DTE, the data currently stored by the PAD
is forwarded.

Table 12-8: Echo

Value Description

0 No character echo
1 Character echo enabled (under the restraints or (parameter 20)

during all modes of the PAD *

UTA220/UTA220k 12-21

D-Channel X.25

*default

If a data forwarding ch aracter’s function is duplicated , the
associated functi on for the characte r is according to fol lowing
priority:

1. PAD recall

2. Command signal delimiter

3. XON and XOFF

4. Line display

5. Character delete

6. Line delete

7. Data forwarding

For example, if the character DLE i s assigned to two functions
data forwarding (parameter 3 = 126) and PAD recall
(parameter 1 = 1), DLE is trea ted as t he PAD recall charact er.
The PAD rec all functio n has highe r priority th an the data
forwarding function. This also applies to: BS, CAN, DC1,
DC2, DC3, and DC4 (refer to Appendix F).

Parameter 4: Selection of Idle Timer Delay

This parameter designates the amount of idle time (time in
which a character is not received) allowed after the PAD has
received a character from the local DTE devi ce before th e
entire PAD buffer is forward ed. The idl e timer is not sta rted if
parameter 15 is ena bled. The decimal value stored in para meter
4 designates the timer value in 20ths of a second.

*default

Table 12-9: Data Forwarding Character

Value Description

0 No designated data forwarding character
2 Data forwarding on carriage return *

126 Data forwarding on all ASCII decimal characters from 0 to 31 and

character DEL. (Refer to Appendix F)

Table 12-10: Idle Timer Delay

Value Description

0 No idle timer delay *

1 to 255 Specifies the timer value in 20ths of a second

12-22 UTA220/UTA220k

D

-Channel X.25

Parameter 5: Ancillary Device Control

Parameter 5 specifies whether or not flow control of the local
DTE device (ancillary dev ice) by the PAD can occur , and if so,
what modes of the PAD the PAD flow control of the local DTE
are allowed. Flow control of the lo cal DTE device is handled in
conjunction with S54 (DTE f low cont rol re giste r). The type of
flow contr ol the PAD transmits to the local DT E device is set
according to the setting of S54. For example, if S54 is set for
CTS flow co ntrol, the PA D will flow control the local DTE
device by turning of f the CTS pin when the PAD can n o longer
accept any character s f ro m t he loc al DTE. W hen t he PAD can
resume accepting chara cters from the local DTE, the PAD turns
the CTS pin on. If all th e DTE flow control options a re disabled
(default), the PAD will transmit XON (Ctrl Q) and XOFF
(Ctrl S) to the local DTE for flow control.

*default

Note: The function of pa rameter 5 differs from t he 1984 CCITT
X.3 Specification. The specification indicates that only XON
and XOFF can be transmitted to the DTE for the purpose of
flow control. The TA does not restrict the type of flow control
used on the local DTE. The se tting of the AT command indicat es
the type of flow c ontrol sent to the DTE. Thus, if the DTE de vice
only recognizes CTS flo w control, the PAD can still flow contr ol
the DTE.

Parameter 6: Control of PAD Service Signals

Parameter 6 specifi es whether the P AD prompt or PAD ser vice
signals are transmi tted to the local DTE devi ce by the PAD, and
the format of those s ervice signals. The PAD servi ce signals are
character messages tra nsmitted t o the loca l DTE devic e by the
PAD in response to PAD commands issued by the local DTE
or to inform the user of a pa cket or network action (i.e., call reset
etc.). The PAD prompt is the character *. It is transmitted by
the PAD to the local DTE device when the PAD is in PAD
command mode to prompt the user to enter a PAD command.

For non-interact ive applications, the serv ice signal transmission
to the local DTE may be disabled as the transmission service
signals can appear to be part of the received data.

Table 12-11: Ancillary Device Control

Value Description

0 No PAD flow control
1 PAD data transfer flow control
2 PAD data transfer and PAD command mode flow control *

UTA220/UTA220k 12-23

D-Channel X.25

*default

Parameter 7: Action of PAD on Break from DTE

Parameter 7 specifies the action taken by the PAD when the
PAD receives a break signal from the local DTE. The break
signal allows the DTE to signal the PAD without loss of
character transpar ency. The PAD a lso rela ys a break signal t o
the DTE when the PAD receive s a break from the remote DTE.
The PAD responds to the break only when a packet call is
established and the PAD is in the PAD data transfer mode.
Upon receipt of the break, all data stored by the PAD is
forwarded. The break si gnal consists of binary 0s for more than
135 ms.

Parameter 7 can be any added combination of the above values.
* default

Table 12-12: PAD Service Signal Control

Value Description

0 No PAD service signals or PAD prompt
1 PAD service signals in standard form but no PAD prompt
5 PAD service signals and PAD prompt in standard form *

Table 12-13: PAD Action on DTE Break

Value Description

0 The PAD does nothing on receipt o f a break in PAD data transfer, PAD

command, or PAD connect-in-progress mode (while establishing a
call) *

1 An expedited interrupt packet is transmitted by the PAD prior to the

forwarding of the store d PAD data. If a previously transmitted interrupt
is not acknowledged, the break interrupt will wait until
acknowledgment of the previous interrupt is received.

2 A reset request packet is transmitted to the remote end after the

forwarding of the PAD data.

5 The PAD transmits an expedited interrupt packet, any stored PAD data

is forwarded, and an a X.29 indication of break packet is trans mitted

8 Escape from PAD data transfer. Equivalent to a PAD recall

21 Transmitted data is discarded, and expedited interr upt packet is

transmitted if there is no outstanding interrupt, stored PAD data is
forwarded, and an X.29 indication of break packet is transmitted.
When data must be discarded, parameter 8 is set to 1. When the break
actions are completed, parameter resets to 0.

12-24 UTA220/UTA220k

D

-Channel X.25

Parameter 8: Discard Output

Parameter 8 specifies whether data r eceived by the PAD from
the remote end is transmitted to the loca l DTE device. The
control of data delivery is only possible when the PAD is in
data transfer mode (i.e., this is the mode when data is being
delivered to the local DTE device).

* default

Parameter 9: Padding after Carriage Return

Parameter 9 specif ies the number of padding (null) characte rs
inserted after a ca rriage return, whi ch is transmitted or echoed
to the local DTE device. This pr ovides the printing mechanism
of the local DTE device time to physically comp lete the
carriage return (ad vance the prin ting head to the beginning of
the line). Once complete, th e PAD can resume sending data to
the local DTE device without losing data.

Parameter 9 also applie s to the number of padding char act er s
inserted after t he format effecter (carriage return and line feed).
The format effecter is sent in conjunction with PAD service
signals to the local DTE device when the PAD is in PAD
command mode.

* default

Table 12-14: Discard Output

Value Description

0 Normal data delivery *
1 Discard output to the DTE

Table 12-15: Padding After Carriage Return

Value Description

0 No padding after any carriage return or the line feed of the format

effecter. *
If parameter 8 is set to 0 then:

DTE Speed # of Padding Characters

110 2
300 4
600 4

1200 4

>1200 0

1 to 255 Specifies the number of padding characters