V.F 28.8/33.6 Modem, DeskTop Platform

V.F 28.8/33.6 Modem, DeskTop Platform
054R207-000
Issue 11
June 2003
V.F 28.8/33.6 Modem,
DeskTop Platform
Installation and Operation
Copyright
©2003 General DataComm, Inc. ALL RIGHTS RESERVED.
This publication and the software it describes contain proprietary and
confidential information. No part of this document may be copied,
photocopied, reproduced, translated or reduced to any electronic or machinereadable format without prior written permission of General DataComm, Inc.
The information in this document is subject to change without notice. General
DataComm assumes no responsibility for any damages arising from the use of
this document, including but not limited to, lost revenue, lost data, claims by
third parties, or other damages.
If you have comments or suggestions concerning this manual, please contact:
General DataComm, Inc.
Technical Publications Department
6 Rubber Avenue
Naugatuck, Connecticut USA 06770
Telephone: 1 203 729-0271
Trademarks
All brand or product names are trademarks or registered trademarks of their
respective companies or organizations.
Documentation
Revision History
Issue
Number
Date
Description of Change
1
Initial Release
2
Update
3
Update
4
Update
5
Update
6
Update
7
Update
8
Update
9
Nov 1999
New format and incorporation of erratas
10
April 2002
Update
11
June 2003
Update
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V.F 28.8/33.6 Modem, DeskTop Platform
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Preface
Scope
This manual describes how to install and operate the DeskTop V.F
28.8/33.6 Modem. The information contained in this manual has been
carefully checked and is believed to be entirely reliable. However, as
General DataComm improves the reliability, function, and design of
their products, it is possible that information may not be current. For
the latest updates and product release notes on this product, consult the
GDC web site at: http://www.gdc.com or your GDC representative.
General DataComm, Inc.
Technical Publications Department
6 Rubber Avenue
Naugatuck, Connecticut, USA 06770
Tel: 1 203 729-0271
Manual Organization
This manual is divided into the following chapters:
Chapter 1, Introduction
Chapter 2, Installation
Chapter 3, Basic Operation
Chapter 4, AT Command Set Operation
Chapter 5, V.25 bis Command Set Operation
Chapter 6, Tests
Appendix A, Technical Characteristics
Appendix B, Business Equipment Interface (EIA/TIA-232-E, ITU-T
V.24/V.28/ISO 2110)
Appendix C, Business Equipment Interface (EIA/TIA-530-A, ITU-T
V.10/V.11/V.24/ISO 2110)
Appendix D, Business Equipment Interface (ITU-T V.35/V.24/V.28/
ISO 2593)
Appendix E, ASCII/EBCDIC Character Sets And Hexadecimal/Binary
Conversions
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Safety Information
This manual should be read in its entirety and all procedures
completely understood before installing or operating the unit. The
notes that appear throughout this manual must be read prior to any
installation or operating procedure. Examples of notes used in this
manual are shown below.
Note
Indicates something you should be particularly aware of;
something not readily apparent. A note is typically used as a
suggestion.
Important
Indicates an emphasized note. It is something you should be
particularly aware of; something not readily apparent.
Important is typically used to prevent equipment damage.
The CAUTION, WARNING, and DANGER statements that appear
throughout this manual are intended to provide critical information for
the safety of both the service engineer and operator. These statements
also enhance equipment reliability. The following definitions and
symbols for CAUTION, WARNING, and DANGER as they are used
comply with ANSI Z535.2, American National Standard for
Environmental and Facility Safety Signs, and ANSI Z535.4, Product
Safety Signs and Labels, issued by the American National Standards
Institute.
CAUTION indicates conditions or practices that can cause
damage to equipment or loss of data.
WARNING indicates a potentially hazardous situation
which. if not avoided, may result in minor to moderate injury.
It may also be used to alert against unsafe practices.
Note
DANGER indicates an imminently hazardous situation
which, if not avoided, will result in death or serious injury.
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Safety Guidelines
Always use the following guidelines when unsafe conditions exist or
when potentially hazardous voltages are present:
•
•
•
•
•
•
Always use caution and common sense.
Repairs must be performed by qualified service personnel only.
To reduce the risk of electrical shock, do not operate equipment
with the cover removed.
Never install telephone jacks in a wet location unless the jack is
designed for that location.
Never touch uninsulated telephone wires or terminals unless the
telephone line is disconnected at the network interface.
Never install telephone wiring during an electrical storm.
Antistatic Precautions
Electrostatic discharge (ESD) results from the buildup of static
electricity and can cause computer components to fail. Electrostatic
discharge occurs when a person whose body contains a static buildup
touches a computer component. This product may contain staticsensitive devices that are easily damaged. Proper handling, grounding
and precautionary ESD measures are essential when installing parts or
cards. Keep parts and cards in antistatic packaging when not in use or
during transport. If possible, use antistatic floorpads and workbench
pads.
When handling components, always use an antistatic wrist strap
connected to a grounded equipment frame or chassis. If a wrist strap is
not available, periodically touch an unpainted metal surface on the
equipment. Never use a conductive tool, like a screwdriver or a paper
clip, to set switches.
FCC Part 68 Compliance
Connection of data communications equipment to the public telephone
network is regulated by FCC Rules and Regulations. This equipment
complies with Part 68 of these regulations which require all of the
following:
All connections to the telephone network must be made using standard
plugs and telephone company provided jacks or equivalent.
Connection of this equipment to party lines and coin telephones is
prohibited. A label on the component side of the unit’s printed circuit
board provides the FCC Registration number for the unit. If requested,
give this information to the telephone company. To connect the
product to the Public Telephone Network, you are required to give the
following information to the telephone company:
•
•
•
FCC Registration Number: AG6USA-75466-MD-E 0.4B
Service Order Code: 9.0Y
Telephone Company jack type: RJ45S
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The telephone company may discontinue your service if the unit causes
harm to the telephone network. If possible, you will be notified of such
an action in advance. If advance notice is not practical, you will be
notified as soon as possible and will be advised of your right to file a
complaint with the FCC. The telephone company may change its
communication facilities, equipment, operations and procedures where
reasonably required for operation. If so, the telephone company will
notify you in writing. All repairs or modifications to the equipment
must be performed by General DataComm. Any other repair or
modification by a user voids the FCC registration and the warranty.
Part 15 Compliance
This device complies with Part 15 Class A of the FCC rules. Operation
is subject to the following two conditions:
1.
2.
This device may not cause harmful interference and
This device must accept any interference received, including
interference that may cause undesired operation.
Industry Canada Notification
The Industry Canada label identifies certified equipment. This
certification means that the equipment meets telecommunications
network protective, operation and safety requirements as prescribed in
the appropriate Terminal Equipment Technical Requirements
document(s). The Department does not guarantee the equipment will
operate to the user's satisfaction.
Before installing this equipment, users should ensure that it is
permissible to be connected to the facilities of the local
telecommunications company. The equipment must also be installed
using an acceptable method of connection. The customer should be
aware that compliance with the above conditions may not prevent
degradation of service in some situations.
Repairs to certified equipment should be coordinated by a
representative designated by the supplier. Any repairs or alterations
made by the user to this equipment, or equipment malfunctions, may
give the telecommunications company cause to request the user to
disconnect the equipment.
Users should ensure for their own protection that the electrical ground
connections of the power utility, telephone lines and internal metallic
water pipe system, if present, are connected together. This precaution
may be particularly important in rural areas.
Caution: Users should not attempt to make such connections
themselves, but should contact the appropriate electric inspection
authority, or electrician, as appropriate.
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Notice: The Ringer Equivalence Number (REN) assigned to each
terminal device provides an indication of the maximum number of
terminals allowed to be connected to a telephone interface. The
termination on an interface may consist of any combination of devices
subject only to the requirement that the sum of the Ringer Equivalence
Numbers of all the devices does not exceed 5.
Electromagnetic Compatibility
This Class A digital apparatus complies with Canadian ICES-003.
Avis D’industrie Canada
L’étiquette d’Industrie Canada identifie le matériel homologué. Cette
étiquette certifie que le matériel est conforme aux normes de
protection, d’exploitation et de sécurité des réseaux de
télécommunications, comme le prescrivent les documents concernant
les exigences techniques relatives au matériel terminal. Le Ministère
n’assure toutefois pas que le matériel fonctionnera à la satisfaction de
l’utilisateur.
Avant d’installer ce matériel, l’utilisateur doit s’assurer qu’il est
permis de le raccorder aux installations de l’entreprise locale de
télécommunication. Le matériel doit également être installé en suivant
une méthode acceptée de raccordement. L’abonné ne doit pas oublier
qu’il est possible que la comformité aux conditions énoncées ci-dessus
n’empêche pas la dégradation du service dans certaines situations.
Les réparations de matériel homologué doivent être coordonnées par
un représentant désigné par le fournisseur. L’entreprise de
télécommunications peut demander à l’utilisateur de débrancher un
appareil à la suite de réparations ou de modifications effectuées par
l’utilisateur ou à cause de mauvais fonctionnement.
Pour sa propre protection, l’utilisateur doit s’assurer que tous les fils de
mise à la terre de la source d’énergie électrique, des lignes
téléphoniques et des canalisations d’eau métalliques, s’il y en a, sont
raccordés ensemble. Cette précaution est particulièrement importante
dans les régions rurales.
Avertissement: L’utilisateur ne doit pas tenter de faire ces
raccordements lui-même; il doit avoir recours à un service d’inspection
des installations électriques, ou à un électricien, selon le cas.
Avis: L’indice d’équivalence de la sonnerie (IES) assigné à chaque
dispositif terminal indique le nombre maximal de terminaux qui
peuvent être raccordés à une interface. La terminaison d’une interface
téléphonique peut consister en une combinaison de quelques
dispositifs, à la seule condition que la somme d’indices d’équivalence
de la sonnerie de tous les dispositifs n’excède pas 5.
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La Compatibilité d’ Eléctro-magnetique
Cet appareil numerique de la classe A est conforme a la norme NMB003 du Canada.
Deutschland
Installations Anweisungen: Installieren Sie die Telefonleitungen nicht
während eines Gewitters. Installieren Sie die Telefonleitungen nicht in
einem feuchten Raum, auβer die Dose entspricht den Vorschriften für
Feuchträume. Berühren Sie unisolierte Telefonleitungen oder
Einrichtungen nicht, auβer diese sind vom Telefonnetz getrennt.
Vorsicht bei der Installierung oder Änderung von Telefonleitungen.
Achtung: Es gibt keine durch den Benutzer zu wartende Teile im Gerät.
Wartung darf nur durch qualifiziertes Personal erfolgen.
EC Declaration of Conformity
We:
General DataComm Inc.
6 Rubber Avenue
Naugatuck, CT 06770, U.S.A.
The products to which this declaration relates are in conformity with
the following relevant harmonized standards, the reference numbers of
which have been published in the Official Journal of the European
Communities.
Electromagnetic Compatibility
EN 55022: 1994
Specification for limits and methods of measurement of radio
interference characteristics of information technology equipment.
EN 50082-1: 1992
Generic immunity standard Part 1 Residential, Commercial, and Light
Industry.
Safety
EN 60950: 1995 A1 through A3
Low Voltage Directive relating to electrical equipment designed for
use within certain voltage limits.
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Support Services and Training
General DataComm offers two comprehensive customer support organizations
dedicated to pre-and post-sale support services and training for GDC products.
Corporate Client Services and Factory-Direct Support & Repair assist
customers throughout the world in the installation, management, maintenance
and repair of GDC equipment. Located at GDC’s corporate facility in
Naugatuck, Connecticut USA, these customer support organizations work to
ensure that customers get maximum return on their investment through costeffective and timely product support.
Corporate Client Services
Corporate Client Services is a technical support and services group that is
available to GDC customers throughout the world for network service and
support of their GDC products. Customers get the reliable support and training
required for installation, management and maintenance of GDC equipment in
their global data communication networks. Training courses are available at
GDC corporate headquarters in Naugatuck, Connecticut, as well as at customer
sites.
Factory Direct Support & Repair
GDC provides regular and warranty repair services through Factory Direct
Support & Repair at its U.S. headquarters in Naugatuck, Connecticut. This
customer support organization repairs and refurbishes GDC products, backed
by the same engineering, documentation and support staff used to build and test
the original product. Every product received for repair at Factory Direct
Support & Repair is processed using the test fixtures and procedures
specifically designed to confirm the functionality of all features and
configurations available in the product.
As part of GDC’s Factory Direct program, all product repairs incorporate the
most recent changes and enhancements from GDC Engineering departments,
assuring optimal performance when the customer puts the product back into
service. Only GDCís Factory Direct Support & Repair can provide this added
value.
Contact Information
General DataComm, Inc.
6 Rubber Avenue
Naugatuck, Connecticut 06770 USA
Attention: Corporate Client Services
Telephones: 1 800 523-1737
1 203 729-0271
Fax: 1 203 729-3013
Email: [email protected]
General DataComm, Inc.
6 Rubber Avenue
Naugatuck, Connecticut 06770 USA
Attention: Factory Direct Support & Repair
Telephones: 1 800 523-1737
1 203 729-0271
Fax: 1 203 729-7964
Email: [email protected]
Hours of Operation:
Monday - Friday 8:30 a.m. - 5:00 p.m. EST
(excluding holidays)
http://www.gdc.com
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V.F 28.8/33.6 Modem DeskTop Platform
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054R207-000
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Table of Contents
Preface
Chapter 1: Introduction
V.F 28.8/33.6 Features.....................................................................1-1
Description.......................................................................................1-2
Modem Equipment ..........................................................................1-2
DTE Cables .................................................................................1-3
Software Selection ...........................................................................1-3
Fax ...................................................................................................1-3
Chapter 2: Installation
Unpacking Your Modem .................................................................2-1
Modem Installation ..........................................................................2-1
Special Considerations for High Data Rates ...............................2-3
Verifying Your Connections .......................................................2-4
Cover Removal And Replacement ..................................................2-5
Option Jumpers ................................................................................2-5
Option Plug-in Cards .......................................................................2-6
VF Card .......................................................................................2-6
DTE Interface Card .....................................................................2-6
Chapter 3: Basic Operation
Using The Front Panel .....................................................................3-1
Using the Keypad ........................................................................3-1
Call Control ...................................................................................3-15
Manual Call Initiation................................................................3-15
Manual Call Initiation with a Stored Number ...........................3-16
Automatic Call Initiation in Response to DTR .........................3-16
Completing a Connection ..........................................................3-18
Call Answering - Automatic......................................................3-18
Call Answering - Manual ..........................................................3-18
Disconnecting a Call..................................................................3-19
Passwords ......................................................................................3-19
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Table of Contents
Security Callback ...................................................................... 3-20
On-line Password Callback Extensions .................................... 3-21
Communication Operation and AT Commands............................ 3-22
Command Mode and Data Mode.............................................. 3-22
AT Command Mode...................................................................... 3-23
Configuration Profiles............................................................... 3-23
Command Syntax...................................................................... 3-24
Command Buffer ...................................................................... 3-25
Automatic DTE Speed and Parity Detection ............................ 3-25
Remote Configuration Using the AT Commands..................... 3-26
Data Mode ..................................................................................... 3-27
Asynchronous Operation............................................................... 3-28
Error Correcting Modes ............................................................ 3-29
V.42 (LAPM) Reliable Mode Error Correction........................ 3-29
Non-Error Correcting Modes.................................................... 3-29
Wire Mode ................................................................................ 3-30
Direct V.14 Asynchronous Mode ............................................. 3-30
V.13 Mode ................................................................................ 3-30
Flow Control ............................................................................. 3-30
Software Flow Control.............................................................. 3-31
Hardware Flow Control ............................................................ 3-31
Synchronous Operation ................................................................. 3-32
Synchronous Operating Modes................................................. 3-32
Asynchronous Dialing with Synchronous Transmission .......... 3-32
Direct Dialing in Synchronous Mode ....................................... 3-33
Normal Synchronous Mode ...................................................... 3-33
V.13 Synchronous Mode .......................................................... 3-33
Synchronous Compression Mode ............................................. 3-34
Clock Selection ......................................................................... 3-35
Switched Network Operation ........................................................ 3-36
Telephone Lines........................................................................ 3-36
Private Line Operation .................................................................. 3-36
Two-wire or Four-wire Selection.............................................. 3-37
Other Configuration .................................................................. 3-37
Transmit Level .......................................................................... 3-38
Automatic and Manual Handshaking........................................ 3-38
Auto Dial Restoral .................................................................... 3-39
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Table of Contents
Testing The Modem .......................................................................3-40
Chapter 4: AT Command Set Operation
Commanding The Modem ...............................................................4-1
AT Command Reference ..............................................................4-24
Chapter 5: V.25 bis Command Set Operation
108 Modes........................................................................................5-1
108.2 Mode ..................................................................................5-1
108.1 Mode ..................................................................................5-2
Operating Procedures .......................................................................5-2
Commanding The Modem ...............................................................5-2
V.25 bis Configuration Commands .............................................5-5
V.25 bis Communication Commands..........................................5-9
ITU-T V.25 bis Command Set Operating Procedures ...................5-11
108.2 Mode Operating Procedures ............................................5-11
108.2 Call Establishment Procedure..........................................5-13
108.1 Mode Operating Procedures ............................................5-14
V.25 bis 108.2 Mode Interface Specifications ...............................5-16
Interface Connections ................................................................5-16
Synchronous Format Selection ..................................................5-17
Data Rate ...................................................................................5-18
Modem Test Modes ...................................................................5-18
Chapter 6: Tests
Analog Loopback .............................................................................6-3
Analog Loopback With Self-Test ....................................................6-4
Digital Loopback..............................................................................6-5
Remote Digital Loopback ................................................................6-6
Remote Digital Loopback With Self-Test .......................................6-7
End-to-End Self-Test .......................................................................6-9
RDLB Requests..............................................................................6-10
Maintenance ...................................................................................6-10
Connections ...............................................................................6-10
Cleaning .....................................................................................6-10
Appendix A: Technical Characteristics
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Table of Contents
Appendix B: Business Equipment Interface (EIA/TIA-232-E,
ITU-T V.24/V.28/ISO 2110)
Appendix C: Business Equipment Interface (EIA/TIA-530-A,
ITU-T V.10/V.11/V.24/ISO 2110)
Appendix D: Business Equipment
Interface
(ITU-T V.35/V.24/V.28/ISO 2593)
Appendix E: ASCII/EBCDIC Character Sets And
Hexadecimal/Binary Conversions
Index
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Chapter 1: Introduction
V.F 28.8/33.6 Features
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Integral synchronous/asynchronous operation.
Synchronous DTE rates to 28.8/33.6K.
Asynchronous DTE rates to 128K.
Supports DCE rates from 2.4 to 33.6 Kbps.
2-wire, full-duplex, switched network operation with
programmable or permissive transmit levels.
2- or 4-wire private line operation, with selectable transmit level.
Automatic VF line rate determination in V.34 and V.32 bis
modes, with fallforward/fallback.
Auto Dial Restoral to restore a failed private line link over the
switched network.
Synchronous data compression (supports rates up to 128 Kbps).
EIA/TIA-602 "AT" Command Set support.
V.25 bis compatible command protocol support.
Remote Configuration to change a remote modem's user
configuration profile.
Front panel keypad and LCD screen for configuration and testing.
Flash memory for downloading modem firmware.
Permanent storage of modem configuration profiles in nonvolatile memory.
External, Internal or Receiver Recovered transmit timing.
Maximum line rate selection.
Asynchronous character lengths of 8, 9, 10 and 11 bits.
Password security.
Security Callback to prevent unauthorized access to a remote
modem.
Intelligent Serial Terminal Dialer via the DTE interface, using the
AT Command Set.
Stores up to ten telephone numbers for easy dialing.
Pulse or tone dialing.
Manual or automatic answer.
Audible Call Progress Monitor.
Analog Loopback with and without Self-Test features.
Digital Loopback and Remote Digital Loopback.
End-to-End Self-Test (511 or in FSK ALT pattern).
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Front panel lockout.
Optional ITU-T V.35 and EIA RS-530A DTE interfaces.
Supports FAX Class 1 operation using V.27 or V.29 modulation.
On-line compatible with all other modems that comply with V.34.
Description
The GDC V.F 28.8/33.6 modem is a universal, full-duplex, multi-speed
modem that provides 28.8 kbps to 300 bps operation over the telephone
(VF) line. It can be connected to a 2-wire switched line, a 2-wire private
line, or a 4-wire private line.
The modem can support asynchronous or synchronous DTE data rates
up to 128 Kbps. Operation can be synchronous or character
asynchronous at all speeds down to 1200 bps. Operation is
asynchronous at 0 to 300 bps. Synchronous rates above 28.8 Kbps
require use of the modem's synchronous data compression feature.
The modem supports the following protocols:
• V.34 for negotiated high-data-rate connections
• V.42 (LAPM) error correction
• V.42 bis data compression
• ITU-T (formerly CCITT) V.32 bis, V.32, V.22 bis, V.22, V.21
• Bell 212A and Bell 103 specifications
The V.F 28.8/33.6 provides automatic dial (AT Command) and
automatic answer for switched network operation. It also supports 2and 4-wire private line operation.
The V.F 28.8/33.6 can be controlled in a number of ways. It can accept
commands from its local DTE using either the AT command set or the
ITU-T V.25 bis command set. The AT commands can also be used for
remote configuration performed through an off-site V.F 28.8/33.6
modem and DTE. The modem includes front panel controls for
configuration and testing.
Modem Equipment
The V.F 28.8/33.6 modem is available in a variety of models. When
unpacking the modem, check that all components are included. (Each
modem includes this manual, the Operation and Installation Manual,
GDC P/N 054R207-000.)
Table 1-1 lists the 117 V ac, 60 Hz models, each of which includes
GDC power supply P/N 750-015-001.
Table 1-2 lists the 220 V ac, 50/60 Hz models, each of which includes
GDC power supply P/N 750-015-101.
Appendix A, Technical Characteristics describes the V.F 28.8/33.6's
technical characteristics.
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DTE Cables
With the EIA/TIA-232-E (ITU-T V.24/V.28/ISO 2110) DTE interface,
use standard EIA/TIA-232-E cables (except as noted in Chapter 2,
Installation under Special Considerations for High Data Rates).
With the ITU-T V.35 (ITU-T V.24/V.28/V.35/ISO 2593) DTE
interface, use GDC adapter cable P/N 027H572-001.
With the EIA/TIA-530-A (ITU-T V.10/V.11/V.24/ISO 2110
Amendment 1) DTE interface, use GDC cable P/N 027H525-XXX.
Software Selection
There are two types of computer software for use with a modem:
terminal emulation software and data communications software.
Terminal emulation software essentially "downgrades" your computer
to a dumb terminal. It allows you to type at the keyboard and see
responses on the video display or printer. Emulation programs are
often used to communicate with main-frame or mini-computers, and
usually do not support disk management or file transfers.
A full-featured data communications software package does allow file
transfers, as well as providing a dial directory, a script language for
automated sessions, and a host of other features. Of course, the more
powerful and flexible a software package is, the more difficult it may
be to master.
To take full advantage of the features of the V.F 28.8/33.6 modem,
your selected program should allow turning off the autobaud feature.
You should also be able to toggle both XON/XOFF and hardware flow
control. In addition, it should support several file transfer protocols
designed to be used with an error-correcting modem.
Although your modem will work with most standard communications
programs and file protocols such as XMODEM, there may be a
throughput penalty when using a software error-detecting protocol due
to the redundant error-checking overhead. File transfer protocols that
are tailored for use with error-correcting modems are YMODEM-G
and IMODEM.
Fax
The modem (Revision G software and later) can support FAX Class 1
transmission and reception. The function requires use of ITU-T V.27
or V.29 modulation.
QuickLink FAX software is available separately from GDC to support
the modem’s FAX Class 1 transmission and reception capabilities.
The GDC part number for that software is 759-052S001.
Note
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Before you load and activate the fax software, make sure
that the modem is connected to the PC and switched On.
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Table 1-1
P/N
117 V AC Models
Network Type
DTE Interface
Cables
060A010
SN
PL
232
-001
9
9
9
See note 1
9
See note 2
9
See note 1
9
See note 2
-011
9
-101 *
9
-111 *
9
-201
9
-211
9
-301
9
-311
9
9
530
9
9
V.35
9
See note 1
9
See note 2
9
See note 1
9
See note 2
* For sale only in USA and countries with USA-like requirements.
Notes
054R207-000
Issue 11
1. Includes one 830-027-407 (for switched network
permissive connection) and two 830-028-807 (for
switched network programmable connection or fourwire private line).
2. Includes one 830-027-407 (for switched network
permissive connection) and one 830-028-807 (for
switched network programmable connection).
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
1-4
Table 1-2
P/N
220 V AC Models
Network Type
DTE Interface
Cables
060A010
SN
-002
9
-012
9
-102 *
9
-112 *
9
-202
9
-212
9
-302
9
-312
9
PL
9
9
232
530
V.35
9
See note 1
9
See note 2
9
See note 1
9
See note 2
9
9 See note 1
9 See note 2
9
9
See note 1
9
See note 2
* For sale only in USA and countries with USA-like requirements.
Notes
054R207-000
Issue 11
1. Includes one 830-027-407 (for switched network
permissive connection) and two 830-028-807 (for
switched network programmable connection or fourwire private line).
2. Includes one 830-027-407 (for switched network
permissive connection) and one 830-028-807 (for
switched network programmable connection).
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
1-5
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
1-6
Chapter 2: Installation
Note
The installation of this unit is to be done by qualified
service personnel only.
This section describes installation of the V.F 28.8/33.6 modem.
Unpacking Your Modem
When you remove the modem from its box, make sure that it is
undamaged and that the proper cables and an ac power supply are
included. If any of the components are missing, call your local
representative.
Keep the carton and protective packing material so you can repack the
equipment for storage or shipment. If there is any visible damage to the
modem, record it on the freight bill, have the freight carrier
acknowledge it and submit your claim to the carrier
CAUTION
Do not install or operate damaged equipment as safety and
performance may be affected.
Modem Installation
The rear panel of the V.F 28.8/33.6 has several external interface
connectors: an ac power supply receptacle and a power On/Off switch.
Refer to Table 2-3, Table 2-2, and Figure 2-2 for additional details.
Installation procedure:
1.
Turn Off the modem and the equipment connected to it.
2.
For switched network operation, connect the telephone line to the
modem using the modular jack marked SN. For private line
operation, connect the telephone line to the modular jack marked
PL. Refer to Table 2-2 for the pinouts of the modular jacks.
3.
If a telephone is required, connect it to the modem using the
modular jack marked PHONE. (In private line operation, no
telephone is used.)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
2-1
4.
Note
Connect the DTE interface cable to the modem using the female
DB25 connector labeled Business Equipment.
A shielded cable is required to comply with FCC Class B
and EN 55022 Class B EMI requirements.
5.
Plug the other end of the DTE interface cable into the serial port
on your asynchronous DTE. For most computers, this port is
usually located on the back and is often referred to as an RS-232C (the recent terminology is EIA/TIA-232-E), serial, or
asynchronous port. (Check with your computer dealer or
computer manual for the correct connector. Some computers,
such as Macintosh, use different plugs, pin assignments, and
numbers of pins.)
6.
Use a small screwdriver to tighten the screws on the DTE
interface cable. This will ensure that this cable cannot be
accidentally disconnected.
7.
Check that the label on the ac power supply displays the proper
voltage rating for use with the local national requirements.
8.
Connect the ac power supply to the modem by inserting the plug
into the DIN connector labeled POWER.
9.
Plug the ac power supply into a standard ac outlet.
Note
In order to comply with EMI requirements the power
supply box must be located on the floor.
10. Turn On the modem and the equipment.
Note
2-2
When installing the high speed modem on an asynchronous
port, it is important to confirm the highest speed supported
by the DTE. Some asynchronous PC ports are restricted to
9600 bps or 19,200 bps operations. Special boards that
support up to 115,200 bps are available for PCs, but the
communication software that you use must be able to
support it. The Technical Reference Section of your
computer hardware manual provides this information.
Further restrictions may be placed on the asynchronous
port performance by the computer's operating system if
"multitasking" or "Windows" are used. Review your
operating systems limitations before selecting high speed
operations.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Special Considerations for High Data Rates
Because of the high data rates possible with the V.F 28.8/33.6, the type
and length of the DTE cable are important factors in ensuring data
integrity. The modem's higher data rates require the use of shielded
DTE cables. Further, the cable's capacitance and resistance, which vary
with its length, must be evaluated to ensure that it can support the
chosen data rate over the required distance.
Cable capacitance is specified in two categories: conductor-toconductor (C-C) and conductor-to-shield (C-S). Each of those
capacitance values is expressed in PicoFarads per foot (pF/ft). A
cable's total capacitance is arrived at by adding C-C to C-S and
multiplying by its length in feet. The following example illustrates
calculations for the total capacitance of a 10-foot cable with a C-C
capacitance of 12.5 pF/ft and a C-S capacitance of 22.0 pF/ft:
Total capacitance = [(C-C) + (C-S)] * 10
Total capacitance = (12.5 + 22.0) * 10
Total capacitance = 34.5 * 10
Total capacitance = 345 pF
The following table shows the greatest total capacitance tolerated for
each range of data rates.
Data Rate (Kbps)
Total Capacitance (pF)
0.0 - 20.0
2400
20.0 - 30.0
1200
30.0 - 60.0
900
60.0 - 100.0
450
100.0 - 128.0
200
A DTE cable for use with the V.F 28.8/33.6 modem must have total
resistance of 20 ohms or less. To calculate a cable's resistance, multiply
its specified resistance value (in ohms per 1000 feet) by its length (in
feet). The following example illustrates the calculation for a 10-foot
cable with a resistance of 24 ohms/1000 ft:
Total Resistance = (24/1000) * 10
Total Resistance = 0.024 * 10
Total Resistance = 0.24 ohms
054R207-000
Issue 11
V.F 28.8/33.6 Modem
Installation and Operation
2-3
The following table shows for two GDC DTE cables the greatest
lengths that can be used at differing data rates. The two cables shown
are 028H511-XXX (DB25 male-to-female) and 028H502-XXX
(DB25 male-to-male). When ordering these cables, replace the -XXX
with the three-digit dash number that indicates the desired length (50,
25, 10, or 5 feet).
028H511-
Data Rate
(Kbps)
-050
-025
-010
028H502-005
9
0.0 - 20.0
-050
-025
-005
9
20.0 - 30.0
9
9
30.0 - 60.0
9
9
60.0 - 100.0
-010
9
100.0 - 128.0
9
9
9
Verifying Your Connections
Your modem should now be connected. You can verify the connections
by following these steps:
2-4
1.
To verify that the ac power supply is connected properly, see if
the LCD display on the front panel is displaying the Home Screen
(the Home Screen is displayed a few seconds after the GDC
logo). If not, turn Off the modem, then turn it On again. If the
Home Screen still does not appear, then either the ac power
supply is not connected properly, or the modem is not
functioning.
2.
To verify that the switched network telephone line is connected
properly, place a voice call using a telephone plugged into the
modem.
3.
If using a terminal as the DTE, proceed to the next step. If using
a computer as the DTE, then run your communications software
and configure it for terminal emulation. If using an intelligent
communications software package, it may be necessary to
configure it for "dumb" mode. See Chapter 3 for further details.
4.
Type the command AT followed by a carriage return on the DTE.
The modem should respond with an OK message. If the modem
does not respond with an OK message, then either the DTE
interface cable is not connected properly or the DTE is not
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
configured properly. See Appendix A for a complete list of
compatible DTE configurations such as speed and parity.
Note
If several telephone sets share the same extension as the
modem, lifting one of the telephone hand-sets while data is
being received may introduce errors.
Cover Removal And Replacement
If it is necessary to inspect or change the option jumpers, or to inspect
the option plug-in cards, first remove the modem's cover. To remove
the cover:
1.
Turn Off the modem and the equipment connected to it.
2.
Remove all screws from the bottom of the case.
3.
Insert a thin-blade slotted screwdriver into one of the slots along
the bottom rear edge. Tilt the handle slightly away from the unit
to release the internal tab.
4.
With one tab loose, use your fingers to snap open the cover at the
other rear corner. The front panel assembly is connected to the
base card by cables: it is not necessary to un-plug them.
To reinstall the cover:
1.
Hook its front lip onto the two hooks at the front of the base, then
snap the cover shut at the rear.
2.
Replace the screws removed from the bottom of the case.
Option Jumpers
The V.F 28.8/33.6 has only one user-configurable option, jumper (X3).
It sets the line termination impedance in switched network mode (the
impedance in private line mode is fixed at 600 ohms). The factory
default is 600 ohms. Refer to Table 2-1 and Figure 2-1 for details.
There are three other factory-set jumpers. Verify that they are set as
described in Table 2-1 and shown in Figure 2-1.
054R207-000
Issue 11
V.F 28.8/33.6 Modem
Installation and Operation
2-5
Option Plug-in Cards
The V.F 28.8/33.6 is available in several models, and some require
option plug-in cards. There are two types of plug-in cards: the VF card
and the DTE interface card.
Note
These option plug-in cards are not ordered separately nor
are they field-upgradeable: They are included in the
modem top assembly part number (refer to Table 1-1 and
Table 1-2).
VF Card
The VF card allows the factory to configure the modem for individual
national requirements, so a country-specific VF card is installed on
each international model. The VF card also provides private line
circuitry, so it is installed on each domestic model used in a private line
application. The VF card attaches to the modem base card via
connectors XA1JI, XA1J2, XA1J3 and XA1J4, as illustrated in Figure
2-1. It has no option jumpers.
A domestic model used only in a switched network application does
not require a VF card.
DTE Interface Card
The V.F 28.8/33.6 has a built-in EIA/TIA-232-E (ITU-T V.24/V.28/
ISO 2110) DTE interface. There are two other interfaces available that
each require a unique option plug-in card:
•
•
ITU-T V.35 (ITU-T V.24/V.28/V.35/ISO 2593)
EIA/TIA-530-A (ITU-T V.10/V.11/V.24/ISO 2110
Amendment 1)
A DTE interface card attaches to the modem base card via connectors
XA2JI, XA2J2, XA2J3, and XA2J4, as illustrated in Figure 2-1. DTE
interface cards have no option jumpers.
2-6
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
rear edge of base card
XA2J3
XA2J1
Note: The built-in
interface does not
use a DTE interface
card.
DTE interface card
060P016-001 or 060P017-001
XA2J4
XA2J2
XA1J1
XA1J2
VF card
060P015-XXX
G
Y
X
X2
XA1J3
XA1J4
600
X3
900
EN
MP
MC
DIS
X4 X1
front edge of base card
Figure 2-1
054R207-000
Issue 11
PC Card Layout
V.F 28.8/33.6 Modem
Installation and Operation
2-7
Table 2-1
Option
Line
impedance
Option Jumpers
Selection
Jumper
Position
Description
600 ohms
X3
600 *
Matches a 600 ohm line, common
domestically. For switched
network only.
900 ohms
X3
900
Matches a 900 ohm line. For
switched network only.
MUST be in the MP position.
n/a
MP
X1
MP *
n/a
no jumper
X2
no jumper MUST have no jumper installed.
*
n/a
DIS
X4
DIS *
MUST be in the DIS position.
* Factory default position.
Table 2-2
Modular Jack Pinouts
1
Private Line (PL)
Switched Network
(SN)
Pin Number
nc
Four-wire
Tx-A
Two-wire
Tx/Rx-R
2
nc
Tx-B
Tx/Rx-T
3
nc
nc
nc
4
R
nc
nc
5
T
nc
nc
6
nc
nc
nc
7
PR
Rx-B
nc
8
PC
Rx-A
nc
nc = no connection
2-8
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
.
Table 2-3
Rear Panel
Name
Function
PL
8-position modular jack (US RJ45) for connection to a private
line.
SN
8-position modular jack (US RJ45) for connection to a switched
network line.
PHONE
6-position modular jack (US RJ11) for connection to an optional
500- or 2500-type telephone.
Business Equipment A female DB25 connector for connection to a DTE (terminal or
computer).
POWER
A DIN connector for the included ac power supply.
ON/OFF
A switch to turn the modem on or off.
Customer-supplied
DTE interface cable
DTE (computer or terminal)
ON
Business Equipment
PL
OFF
SN PHONE
Power Supply
(must be placed
on floor for
EMI compliance)
Telephone
wall jack*
Optional telephone
(for switched network
operation only)
Figure 2-2
054R207-000
Issue 11
ac wall
outlet
Rear Panel
V.F 28.8/33.6 Modem
Installation and Operation
2-9
054R207-000
Issue 11
V.F 28.8/33.6 Modem
Installation and Operation
2-10
Chapter 3: Basic Operation
Overview
This chapter describes how to operate and configure the V.F 28.8/33.6
modem. Modem control functions can be performed in three ways:
•
•
using the modem's front panel switches and display;
using AT commands sent to the modem from a terminal, PC, or
other asynchronous DTE;
•
using ITU-T V.25 bis commands sent to the modem from a
terminal, PC, or other DTE;
This chapter begins by describing the use of the front panel. That is
followed by the modem's call control functions, which are carried out
principally by means of AT commands. The broader uses of the AT
command set for configuration and control are then described. The AT
command set provides a broader range of capabilities than does the
front panel.
Chapter 4, AT Command Set Operation describes each AT command
in detail, which involves also describing the modem's configurable
characteristics and functions that are controlled by the commands.
Chapter 5, V.25 bis Command Set Operation describes the V.25 bis
command set.
Using The Front Panel
The V.F 28.8/33.6 front panel includes a 12-button keypad for controlling the modem, 10 status LEDs and a 2-line by 16-character LCD
screen. Table 3-1 describes the front panel indicators (the LEDs) Table
3-2 describes the front panel controls (the keypad). The LCD screen
displays the status of the modem and, with the keypad, allows you to
configure and test the modem without connecting a terminal. Table 3-3
through Table 3-12 list the messages you see when using the front
panel, and include the related AT command for each option or
function.
Using the Keypad
•
There are three groups of options or functions - Configuration,
Diagnostics, and Dial. The Configuration group is further divided
into subgroups. Press the CONFIG, DIAG or DIAL key to access
a group. Use the left and right arrow keys to move between options
or functions. Use the up and down arrow keys to scroll through the
list of choices for an option, or to move between subgroups.
054R207-000
Issue 11
V.F 28.8/33.6 ModemDeskTop Platform
Installation and Operation
3-1
•
The modem does not accept configuration from the front panel
while it is in data mode. A switched network modem is in the idle
mode whenever it does not have an active connection, but a private
line modem has to placed in idle mode manually by means of the
Talk/Data switch.
•
An asterisk (*) on the right side of the LCD screen indicates the
displayed option's current configuration. The asterisk is not shown
in Table 3-3 through Table 3-12.
•
Every option or function accessible from the front panel has a
related AT command, but not all AT commands are accessible
from the front panel. A terminal is required to access the entire
complement of AT commands.
•
In Table 3-3 through Table 3-12 the related AT command appears
to the right of each option or function. The AT commands are not
displayed on the LCD screen.
•
The options related to S-Registers (e.g., WAIT DIALTONE) list
only a few commonly used values. To select other values, use the
ATS command.
To dial, view, or store a phone number:
1.
Press DIAL to access the dial group.
2.
Scroll right or left to display the desired dial function.
3.
Scroll down to enter the displayed function.
4.
Enter the cell number or phone number, as prompted.
5.
To insert a dial command modifier (e.g., T for tone
dialing):
6.
3-2
•
Press DIALMOD.
•
Scroll up or down the list to display the desired
modifier.
•
Press ENTER to complete the action.
When dialing or storing, press ENTER to complete the
action. If prompted, press ENTER again to confirm or
ESC to escape.
V.F 28.8/33.6 ModemDeskTop Platform
Installation and Operation
054R207-000
Issue 11
DIAL
1
Ï
General DataComm
V.F 28.8/33.6
General
DataComm
5
9
ON TXD RXD RTS CTS DTR GD DCD OH
TALK/
REDIAL DATA ESC
4
2
3
Í
6
Ð
0
Î
CONFIG DIAG
7
8
DIALMOD ENTER
TM
V.F 28.8/33.6
103
Table 3-1
LED
ON
104
105 106
108
109
142
Front Panel Indicators
Definition
Power On
LED State
On
TXD 103 Transmit Data
RXD 104 Receive Data
Description
The internal +5 V dc power supply is okay.
Off
No +5 V dc.
On
Indicates a SPACE condition in the
transmitted data.
Off
Indicates a MARK condition.
On
Indicates a SPACE condition in the received
data.
Off
Indicates a MARK condition.
RTS 105 Request to
Send
On
The DTE has turned On DTE interface pin 4
(or RTS is On), indicating that the DTE is
requesting the modem for data transmission.
Off
Pin 4 is Off.
CTS 106 Clear to Send
On
The modem has turned On DTE interface
pin 5 (or CTS is On), indi-cating it is ready to
transmit data.
Off
The modem has turned Off pin 5, indicating
it is not ready to transmit data.
On
The DTE has turned On DTE interface pin
20 (or DTR is forced On), indicating it is
ready for data communications.
Off
The DTE has turned Off pin 20, indicating it
is not ready for data communications.
On
The modem is receiving an acceptable
carrier level and is equalized.
Off
The modem is not receiving an acceptable
carrier level or is not equalized.
DTR 108 Data Terminal
Ready
GD
Good Data
(Sheet 1 of 2)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
3-3
Table 3-1
LED
Front Panel Indicators (Continued)
Definition
DCD 109 Data Carrier
Detect
OH
TM 142
Off-Hook
Test Mode
LED State
Description
On
The modem has turned On DTE interface
pin 8 (or DCD is On), indicating it is
receiving data.
Off
The modem has turned Off pin 8, indicating
it is not receiving data.
On
The modem is in the off-hook state.
Off
The modem is in the on-hook state.
Flashing
The modems are handshaking.
On
The modem is in a test mode.
Off
The modem is not in a test mode.
(Sheet 2 of 2)
3-4
V.F 28.8/33.6 ModemDeskTop Platform
Installation and Operation
054R207-000
Issue 11
Table 3-2
Front Panel Controls
Key
Function
DIAL
Dial and store phone numbers. The Dial group includes functions to:
• Manually dial a phone number from the keypad.
• View a stored phone number.
• Store a phone number.
• Dial a stored phone number (a cell).
REDIAL
Redial the last dialed phone number.
TALK/DATA
Switch between talk mode and data mode. Modem must be in talk
mode to accept configuration from the front panel. Private line modem
will only enter Talk mode in response to this switch.
ESC
Return to the home screen, without saving your changes.
·
Move to the screen above, or scroll up through a list of choices.
?
Move to the screen to the left.
CONFIG
Configure modem options. The Configuration group includes the
following subgroups, and each sub-group typically includes a number of
functions, each with a menu of related options for which you can select
a parameter:
• Quick Start
• Network Options
• Terminal Options
• Modem Options
• Dialer Options
• Protocol Options
• Modem Information
• Save Configuration
DIAG
Perform diagnostic tests. The Diagnostics group includes the following
functions for controlling tests:
• ITU-T V.54 Loop 3 with self-test (ANALOOP Self-Test)
• ITU-T V.54 Loop 3 (ANALOOP)
• ITU-T V.54 Loop 2 with self-test (Remote Digital Loopback Self-Test)
• ITU-T V.54 Loop 2 (Remote Digital Loopback)
• End-to-End Self-Test
• ITU-T V.54 Loop 2 (Digital Loopback)
• Cancel Test
‚
Move to the screen below, or scroll down through a list of choices.
‡
Move to the screen to the right.
DIALMOD
Display dial command modifiers to insert in a phone number. Refer to
the D command in Section 4 for a list of dial command modifiers.
ENTER
Select the choice displayed in line 2. When line 2 is blank, ENTER
functions like the Ækey.
0 to 9
Numeric keys, used to enter a phone number or select an item.
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
3-5
Table 3-3
Subgroup
QUICK START
3-6
The Config - Quick Start Subgroup
Option (Line 1)
Choice (Line 2)
Command
SELECT CONFIG
FACTORY DEF 0
FACTORY DEF 1
FACTORY DEF 2
FACTORY DEF 3
USER PROFILE 0
USER PROFILE 1
USER PROFILE 2
USER PROFILE 3
&F0
&F1
&F2
&F3
Z0
Z1
Z2
Z3
ANSWER ORG
MODE
ORG IF NO RING
FORCED ANSWER
AUTO ANS IN ORG
%O0
%O1
%O2
PL HDSK MODE
V.34 ONLY
V32 BIS ONLY
V32 ONLY
&P0
&P1
&P2
SN HDSK MODE
V.34 AUTO
V.34 ONLY
V32 BIS AUTO
V32 BIS ONLY
V32 AUTO
V32 ONLY
V22 BIS ONLY
V22 ONLY
212 ONLY
103 ONLY
V21 ONLY
&H0
&H1
&H2
&H3
&H4
&H5
&H6
&H7
&H8
&H9
&H10
MAX DC RATE
4.8 KBPS, MAX
7.2 KBPS, MAX
9.6 KBPS, MAX
12 KBPS, MAX
14.4 KBPS, MAX
16.8 KBPS, MAX
19.2 KBPS, MAX
21.6 KBPS, MAX
24 KBPS, MAX
26.4 KBPS, MAX
28.8 KBPS, MAX
31.2 KBPS, MAX
33.6 KBPS, MAX
&G5
&G6
&G7
&G8
&G9
&G10
&G11
&G12
&G13
&G14
&G15
&G16
&G17
OPERATING MODE
ASYNC DATA
SYNC DATA
&M0
&M1
SAVE CONFIG
USER PROFILE 0
USER PROFILE 1
USER PROFILE 2
USER PROFILE 3
&W0
&W1
&W2
&W3
V.F 28.8/33.6 ModemDeskTop Platform
Installation and Operation
054R207-000
Issue 11
Table 3-4
Subgroup
NETWORK
OPTIONS
054R207-000
Issue 11
The Config - Network Options Subgroup
Option (Line 1)
Choice (Line 2)
Command
NETWORK
SELECT
SWITCH NETWORK
PL 2W
PL 4W
&L0
&L1
&L2
SN TX LEVEL
PERMISSIVE
PROGRAMMABLE
:P0
:P1
PL TX LEVEL
0 dBm
-1 dBm
-2 dBm
-3 dBm
-4 dBm
-5 dBm
-6 dBm
-7 dBm
-8 dBm
-9 dBm
-10 dBm
-11 dBm
-12 dBm
-13 dBm
-14 dBm
-15 dBm
:T0
:T1
:T2
:T3
:T4
:T5
:T6
:T7
:T8
:T9
:T10
:T11
:T12
:T13
:T14
:T15
AUTODIAL REST
DISABLE
END SESSION
NO END SESSION
&B0
&B1
&B2
PL LOOK BACK
DISABLE
10 MINUTES
20 MINUTES
30 MINUTES
40 MINUTES
S41=0
S41=1
S41=2
S41=3
S41=4
PL DOWN TIME
DISABLE
1 MINUTE
2 MINUTES
3 MINUTES
4 MINUTES
S40=0
S40=1
S40=2
S40=3
S40=4
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
3-7
Table 3-5
Subgroup
TERMINAL
OPTIONS
The Config - Terminal Options Subgroup
Option (Line 1)
Choice (Line 2)
Command
DTE SPEED
AUTOBAUD SPEED
LAST AT SPEED
300
1200
2400
4800
7200
9600
12000
14400
16800
19200
21600
24000
26400
28800
31200
33600
38400
57600
76800
115200
128000
32000
48000
56000
64000
72000
96000
112000
\T0
\T1
\T2
\T3
\T4
\T5
\T6
\T7
\T8
\T9
\T10
\T11
\T12
\T13
\T14
\T15
\T16
\T17
\T18
\T19
\T20
\T21
\T22
\T23
\T24
\T25
\T26
\T27
\T28
\T29
CPM RESP
SPEED
AUTOBAUD SPEED
LAST CON SPEED
300
1200
2400
4800
7200
9600
12000
14400
16800
19200
21600
%R0
%R1
%R2
%R3
%R4
%R5
%R6
%R7
%R8
%R9
%R10
%R11
%R12
(Sheet 1 of 3)
3-8
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054R207-000
Issue 11
Table 3-5
Subgroup
TERMINAL
OPTIONS
(Cont.)
The Config - Terminal Options Subgroup (Continued)
Option (Line 1)
Choice (Line 2)
Command
CPM RESP
SPEED
24000
26400
28800
31200
33600
38400
57600
76800
115200
128000
32000
48000
56000
64000
72000
96000
112000
%R13
%R14
%R15
%R16
%R17
%R18
%R19
%R20
%R21
%R22
%R23
%R24
%R25
%R26
%R27
%R28
%R29
CHAR LENGTH
8 6D
9 7D
10 7D PAR
10 8D
11 7D PAR 2 STP
11 8D PAR
\B0
\B1
\B2
\B3
\B4
\B5
PARITY
EVEN
SPACE
ODD
MARK
AUTO
\P0
\P1
\P2
\P3
\P4
OVERSPEED
NOMINAL
EXTENDED
\A0
\A1
DTE FLOW CTL
DISABLE
XON/XOFF
CTS
RTS/CTS
UNIDIR XON/XOFF
CLK STOPPING
CLK THROTTLING
\Q0
\Q1
\Q2
\Q3
\Q4
TERMINAL
ECHO
DISABLE
ENABLE
E0
E1
DCD CONTROL
ON
REAL
ON WINK DISC
&C0
&C1
&C2
(Sheet 2 of 3)
054R207-000
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V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
3-9
Table 3-5
Subgroup
TERMINAL
OPTIONS
(Cont.)
The Config - Terminal Options Subgroup (Continued)
Option (Line 1)
Choice (Line 2)
Command
CTS CONTROL
CMD ON/RTS
CMD ON/REAL
REAL
FORCED ON
&R0
&R1
&R2
&R3
DTR TRANS CTL
IGNORED
ON/OFF CMD MD
ON/OFF IDLE
ON/OFF RESET
&D0
&D1
&D2
&D3
DSR CONTROL
ON WINK DISC
NORMAL
FOLLOWS DCD
FORCED ON
&S0
&S1
&S2
&S3
DSR IN
ANALOOP
ON
OFF
%D0
%D1
TRANSMIT
CLOCK
INTERNAL
EXTERNAL
WRAP
&X0
&X1
&X2
RTS/CTS DELAY
0 MSEC
15 MSEC
60 MSEC
100 MSEC
S26=0
S26=15
S26=60
S26=100
(Sheet 3 of 3)
Table 3-6
Subgroup
MODEM
OPTIONS
The Config - Modem Options Subgroup
Option (Line 1)
Choice (Line 2)
Command
RINGS TO
ANSWER
DISABLE
1
2
4
8
S0=0
S0=1
S0=2
S0=4
S0=8
FALL FWD
BCKWD
DISABLE
ENABLE
&A0
&A1
TRELLIS
ENABLE
DISABLE
&U0
&U1
RETRAIN
OPTIONS
DISABLE
ENABLE 3 TIMES
FOREVER
%Q0
%Q1
%Q2
(Sheet 1 of 2)
3-10
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Installation and Operation
054R207-000
Issue 11
Table 3-6
Subgroup
MODEM
OPTIONS
(Cont.)
The Config - Modem Options Subgroup (Continued)
Option (Line 1)
Choice (Line 2)
Command
LONG SPACE
DISC
DISABLE
ENABLE
Y0
Y1
SPEAKER
CONTROL
OFF
OFF IN DATA
ON
ON DURING CPM
M0
M1
M2
M3
SPEAKER
VOLUME
LOW
MEDIUM
HIGH
L0 or L1
L2
L3
MAKE BUSY
DISABLE
ON LOSS OF DTR
IN ANALOOP
IN AL NO RS TR
ON LOSS OF RTS
%B0
%B1
%B2
%B3
%B4
POWER UP AS
USER PROFILE 0
USER PROFILE 1
USER PROFILE 2
USER PROFILE 3
&Y0
&Y1
&Y2
&Y3
RDL OPTIONS
ENABLE
DISABLE
&T4
&T5
TEST TIMER
DISABLE
1 MINUTE
5 MINUTES
10 MINUTES
S18=0
S18=6
S18=30
S18=60
DTE TEST CTL
DISABLE
ENABLE
%E0
%E1
DCD LOSS TO
DISC
2 SEC
4 SEC
8 SEC
DISABLE
S10=20
S10=40
S10=80
S10=255
DELAY DTR
10 SEC
20 SEC
30 SEC
S25=10
S25=20
S25=30
CD RESP TIME
500 MSEC
1 SEC
2 SEC
S9=5
S9=10
S9=20
REMOTE
CONFIG
ENABLE
DISABLE
*R0
*R1
(Sheet 2 of 2)
054R207-000
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Installation and Operation
3-11
Table 3-7
Subgroup
DIALER
OPTIONS
3-12
The Config - Dialer Options Subgroup
Option (Line 1)
Choice (Line 2)
Command
COMMAND
FORMAT
AT
V25 bis ASYNC
V25 bis HDLC
V25 bis BISYNC
NONE
%V0
%V1
%V2
%V3
%V4
ALPHA NUMERIC
NUMERIC
ALPHA
V0
V1
CALL PROGRESS
BASIC NO CPM
EXTD RES NO CPM
EXTD DIALTONE
EXTD BUSY
EXTD FULL CPM
X0
X1
X2
X3
X4
RESPONSE
MODE
ENABLE
DISABLE
ENABLE IN ORG
Q0
Q1
Q2
DTR DIAL
DISABLE
CELL 0
CELL 1
CELL 2
CELL 3
CELL 4
CELL 5
CELL 6
CELL 7
CELL 8
CELL 9
DTR TALK/DATA
%Z0
%Z1=0
%Z1=1
%Z1=2
%Z1=3
%Z1=4
%Z1=5
%Z1=6
%Z1=7
%Z1=8
%Z1=9
%Z2
DIAL TYPE
PULSE
DTMF
P
T
PAUSE TIME , <
2 SEC
4 SEC
6 SEC
8 SEC
S8=2
S8=4
S8=6
S8=8
WAIT DIALTONE
2 SEC
4 SEC
8 SEC
S6=2
S6=4
S6=8
V.F 28.8/33.6 ModemDeskTop Platform
Installation and Operation
054R207-000
Issue 11
Table 3-8
Subgroup
PROTOCOL
OPTIONS
054R207-000
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The Config - Protocol Options Subgroup
Option (Line 1)
Choice (Line 2)
Command
ASYNC
PROTOCOL
WIRE MODE
DIRECT MODE
MNP REL MODE
AUTO REL MODE
V42 REL MODE
REL LAPM OR MNP
V13 MODE
\N0
\N1
\N2
\N3
\N4
\N5
\N6
COMPRESSION
DISABLE
ENABLE
TX PATH ONLY
RX PATH ONLY
%C0
%C1
%C2
%C3
BREAK
HANDLING
EXP DST
EXP NON DST
NON EXP-DST
IGNORED
TMD NON EXP-DST
\K0
\K1
\K2
\K3
\K4
MODEM FLOW
CTL
DISABLE
ENABLE
UNIDIRECTIONAL
BIDIR PASSTHRU
\G0
\G1
\G2
\G3
EC DATA IN HSK
NO BUFFER
BUFFER RX DATA
FB w/FB CHR
FB V14 NO BUFR
FB w/FB CHR V14
\C0
\C1
\C2
\C3
\C4
SYNC PROTOCOL
NORMAL SYNC
SYNC V13
SYNC COMPRESSION
\M0
\M1
\M2
V13 MODE
BIDIRECTIONAL
TX ENABLE
RX ENABLE
&E0
&E1
&E2
CONN & LINK
MSGS
SEPARATE MSGS
BOTH AFTER LINK
MICROCOM COMPAT
CONN AFTER LINK
\V0
\V1
\V2
\V3
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
3-13
Table 3-9
Subgroup
MODEM
INFO
The Config - Modem Info Subgroup
Option (Line 1)
Command
PROTOCOL
SELECT
Displays current protocol
n/a
PL CARD
Displays installed VF card
n/a
DTE CARD
Displays installed DTE card
n/a
MODEM
FIRMWARE
Displays letter identifying
firmware revision
n/a
SYMBOL RATE
Displays symbol rate.
n/a
RECEIVE LEVEL
Displays current receive signal
level
n/a
EQLR QUALITY
Displays current signal quality
n/a
Table 3-10
The Config - Save Config Subgroup
Subgroup
Option (Line 1)
SAVE CONFIG
SAVE CONFIG
Table 3-11
Group
TESTS
Choice (Line 2)
Choice (Line 2)
Command
USER PROFILE 0
USER PROFILE 1
USER PROFILE 2
USER PROFILE 3
&W0
&W1
&W2
&W3
The Diag Group
Function (Line 1)
(Line 2)
ANALOOP SELFTEST
ANALOOP
RDL SELFTEST
RDL
SELFTEST
DIGITAL LOOPBACK
CANCEL TEST
Table 3-12
Command
n/a
n/a
n/a
n/a
n/a
n/a
n/a
&T8
&T1
&T7
&T6
&T9
&T3
&T0
The Dial Group
Function (Line 1)
DIAL CELL NUMBER
(Line 2)
n/a
Command
DSx
MANUAL DIAL
n/a
Dn
VIEW CELL
n/a
&V
STORE CELL NUM
n/a
&Zn=nnn
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054R207-000
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Call Control
Call control involves call initiation, completing a connection, call
answering, and disconnecting a call.
The V.F 28.8/33.6 modem can be made to initiate a call in any of three
ways:
•
Manually, using a telephone number supplied at the time the call
is initiated
•
Manually, using a telephone number stored previously in one of
the 10 memory cells provided for that purpose
•
Automatically in response to an Off-to-On transition of the DTR
interface circuit, using a telephone number stored previously in
memory cell 0
The following three headings describe the procedures required for each
type of call initiation. Table 3-4 describes common commands used for
call initiation, answering, and disconnection. Call completion,
answering, and disconnection are discussed under their own headings
following the table.
Manual Call Initiation
The following example illustrates manual call initiation with a
telephone number supplied at the time of the call. At the terminal or
computer keyboard, type
AT DP 9W (809) 555-1234 (enter)
where:
AT
AT command prefix, instructs modem to pay attention to the
characters that follow
D
dial command, instructs modem to dial
9
instructs modem to dial 9 (to reach an outside line)
W
dial modifier, instructs modem to wait for a dial tone before
continuing
(809) 555-1234 number modem is to dial - it will ignore parentheses, spaces,
and hyphens
(enter)
pressing Enter or Return key sends command line to the
modem
P
dial modifier, instructs modem to use pulse dialing
The description of the Dial (Dn) command that appears in Chapter 4,
AT Command Set Operation includes the functions of all dial modifier
characters (such as P and W in this example).
054R207-000
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V.F 28.8/33.6 Modem DeskTop Platform
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3-15
Manual Call Initiation with a Stored Number
The following examples illustrate how to store a telephone number in
one of the modem's memory cells and how to initiate a manual call
using a stored number.
To store a telephone number type
AT &Z3=(809) 555-1234 (enter)
where:
AT
AT command prefix, instructs modem to pay attention to
the characters that follow
&Z3=(809) 555-1234 instructs modem to store the telephone number in nonvolatile memory cell 3
(enter)
pressing Enter or Return key sends command line to
the modem
When you require a modem connection to that stored telephone number
at any later time, type
AT DT S3 (enter)
where:
AT
AT command prefix, instructs modem to pay attention
to the characters that follow
D
dial command, instructs modem to dial
T
dial modifier, instructs modem to use tone dialing
S3
dial modifier, instructs modem to dial the number
stored in memory cell 3
(enter)
pressing Enter or Return key sends command line to
the modem
The description of the Dial (Dn) command that appears in Chapter 4,
AT Command Set Operation includes the functions of all dial modifier
characters (such as T and S in this example).
Automatic Call Initiation in Response to DTR
The AT commands %Z1 and %Z3 both instruct the modem to observe
the state of the Data Terminal Ready (DTR) interface lead, and to
perform automatic call initiation when an Off-to-On transition occurs
on that lead. This function always uses the telephone number stored in
memory cell 0.
When %Z1 is used, the modem will dial automatically only when it
detects a transition on the DTR lead.
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When %Z3 is used, the modem will dial automatically whenever it is
not connected to a remote modem and the DTR lead is On. The significance of this is that the %Z3 command will cause the modem to
perform automatic re-dial for recovery of a broken connection without
requiring intervention by the DTE.
Table 3-13
Command
Common Call Control Commands
This will...
Remember...
AT
get the modem's attention, telling
it that a command is to follow.
this command must always
precede any command line,
except A/.
AT D
get the modem to dial the
specified telephone number that
follows.
your number can contain up to
30 digits.
P
(following D
command)
tell the modem to pulse dial.
you can use dial digits 0 through
9 for pulse dialing.
T
(following D
command)
tell the modem to tone dial.
you can use dial digits 0-9 and
symbols A, B, C, D, #, * for tone
dialing.
W
(as part of dial
command)
indicate to the modem that it must you will use this command when
wait for a dial tone before dialing you have to dial 9 to obtain an
the number that follows.
outside line.
;
(as part of dial
command)
cause the modem to return to the
command mode after it has dialed
the number, rather than
immediately entering data mode.
this will serve to separate a
command string containing
more than 30 characters (so as
not to overflow the buffer).
Sn
(following D
command)
instructs the modem to dial a
previously stored number.
you can store 10 telephone
numbers (n = 0 - 9) up to 30
digits each.
R (as last
cause the modem to establish a
character in
call in answer mode when calling
dial command) an originate-only modem.
the R command must be the last
character in the dial string before
you enter a carriage return.
AT A
force the modem to answer
incoming call.
the modem will not wait for a
ring; no matter what is specified
in the S0 register (see SRegisters in Chapter 4). This
command is used for manually
answering a call.
AT H
force the modem to hang up.
if you are in data mode, you
must first enter command mode
before using this command.
054R207-000
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Installation and Operation
3-17
Completing a Connection
Once you have issued a dial command, the front panel should display
DIALING. If the connection is successful, a CONNECT result code
will appear. This means you are connected to the remote end. See
Chapter 4, AT Command Set Operation for a list of standard and
extended result codes. The result codes appear on your DTE screen
when you issue a command.
Usually you will need to press Enter or Return on the keyboard in order
to receive a prompt from the answering equipment. If you do not do so,
you may be disconnected.
The CTS and DCD indicators will remain on while the V.F 28.8/33.6
modem is connected to the remote end. The TXD indicator will flash
while the modem is sending data and the RXD indicator will flash
while it is receiving data from the remote end.
Call Answering - Automatic
The V.F 28.8/33.6 modem automatically answers and switches to the
data mode if the automatic answering function is enabled. The modem
has built-in "ring-detection" circuitry that can be enabled to provide
automatic response to incoming calls. The value stored in S-Register 0
determines whether auto-answer is enabled. If the value is greater than
0, the modem will count ring signals on the line and display a RING
message for each ring it counts. Once the ring count equals or exceeds
the value of S0, the modem will go off hook and begin the handshaking
procedure.
Note
For more information on the S-Registers, see Chapter 4, AT
Command Set Operation .
The default value of the S0 register n = 1 (auto-answer enabled on the
first ring). The value of n is programmable in AT modes of operation.
For AT operation, refer to S-Register 0 in Chapter 4, AT Command Set
Operation .
Call Answering - Manual
You may prefer that the modem not answer incoming calls automatically; for example, if both voice and data calls will be received on the
same line. Storing the value 0 in S-Register 0 disables auto-answer so
the modem will not answer calls by itself under any circumstances.
You can manually answer a data call from either the keyboard or the
modem's front panel. To answer from the keyboard, enter the command
AT A (enter) upon receiving ring. To answer from the front panel, press
the SEL key three times (this acts as the talk/data switch). Either action
will cause the modem to go off-hook and begin the handshaking
sequence.
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V.F 28.8/33.6 ModemDeskTop Platform
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054R207-000
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Disconnecting a Call
There are several ways to disconnect a call:
•
•
•
•
•
•
H command - disconnects the modem from the VF line. When
using the modem in the asynchronous mode, first type the
ESCAPE sequence (ESCAPE is a programmable character string,
default +++). When the modem returns an OK to the DTE, type
AT H (enter) to terminate the connection.
Loss of DTR - an irreversible data mode disconnect sequence
occurs if circuit 108.2 (DTR) turns Off for more than 50
milliseconds when the modem is in data mode. The modem can be
optioned for circuit 108.2 forced On (terminal dial mode) so that
a DTE cannot cause a disconnect to occur using circuit 108.2.
Character abort - when this feature is enabled, any character sent
from the DTE to the modem at the originate end during dialing or
the handshake sequence will abort the call. %Kn controls this
function in all command modes.
Loss of carrier - the modem will go on-hook if the handshake
sequence is not completed successfully within the time specified
in S-Register 7. This abort timer is programmable for 1 to 30
seconds via the S7=x command. The originating and answering
modem both have the abort timer active during the handshake
sequence.
No answer or busy - when an originating call is not answered
within the time specified by S-Register 7, the modem will
disconnect. If it detects a busy tone, the modem will disconnect
immediately and display the BUSY message.
Long space disconnect - if optioned to do so via the Yn command,
the V.F 28.8/33.6 will initiate and respond to the long space
disconnect procedure. When initiating disconnect (for any reason
except loss of carrier) the modem will transmit 4 seconds of
continuous spacing (receive data clamped to a mark), and then go
on-hook. A modem receiving 1.6 seconds of continuous space on
the VF line will go on-hook. This feature is only functional at
speeds of 2400 bps and lower.
Passwords
The V.F 28.8/33.6 modem provides a variety of configurable password
security arrangements. The two principle categories are the general
security (or "handshake") password, and the on-line password. An
answering modem will terminate the call if it does not receive a
required password.
You can enable either type of password function, or both, by means of
the %Sn command. A general security password, when used, is transmitted and checked as part of the handshake sequence between a
calling modem and an answering modem. When an on-line password
is enabled, the operator placing a call is prompted to supply further
information manually after the modems make their initial connection.
054R207-000
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Installation and Operation
3-19
Note
In order to use a general security password the modems'
handshake modes must be V.34 (&H0, &H1, or &P0
command), V.32 bis (&H2, &H3, or &P1 command) or
V.32 (&H4, &H5, or &P2 command).
The modem has ten memory cells for password storage. The command
for storing a password is %Pn=xxx, where n is the password memory
cell number and xxx is the password. The memory cell number can be
any digit, 0 - 9. The password can be any string of up to ten alphanumeric and punctuation characters (one exception: comma "," may not
be used). The handshake password function always uses the contents of
memory cell 0. The modem compares received on-line passwords to
the contents of all ten memory cells in search of a match.
When an on-line password is required by an answering modem that is
connected to an MMS controller, the remote operator who placed the
call is prompted for three successive items:
ENTER SYSTEM
ENTER USER NAME
ENTER PASSWORD
As each prompt is received, the operator has 15 seconds to respond.
The MMS controller performs the actual verification of the operator's
responses.
A non-MMS answering modem sends only the ENTER PASSWORD
prompt when an on-line password is required.
Security Callback
The Security Callback procedure is invoked by the AT dial command
modifier \n (n = 0 - 9). A call placed using the modifier causes the
answering modem to disconnect after handshaking, then dial a call
back to the modem that made the original call. In the command
modifier, n represents a phone number memory cell in the answering
modem. For example, to call the remote modem at 555-1212 and have
it call the phone number in cell 1, enter:
ATD5551212\1
After handshaking and a short delay, the remote modem terminates the
call, then places a new call to the local modem, using the phone number
that it has stored in cell 1.
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V.F 28.8/33.6 ModemDeskTop Platform
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Use of Security Callback requires the following:
•
•
•
General security password must be enabled in both modems.
The same general security password must be used by both
modems (%Pn command).
The originating modem's phone number must be stored in one of
the answering modem's phone cells.
Note
A telephone number stored for Security Callback use
should always include the :n (retry) modifier. Specify that
the modem will make at least three attempts to dial the
number. Retries compensate for any delay in receiving
dialtone from the Central Office after termination of the
initial connection.
On-line Password Callback Extensions
An operator sending an on-line password may be permitted to include
one of several optional callback extensions. A callback extension
causes the answering modem to disconnect and then call back to the
modem that placed the original call. When you configure a password
memory cell you must enable or disable its callback extension capability by means of the %Fn=x command. In this command n is the cell
number and x defines whether and how the cell's password can be used
for callback (see Chapter 4, AT Command Set Operation for further
details).
The comma, which cannot be used as a character in a password,
functions as a special character to identify the callback request extensions described in the following paragraphs.
There are three callback request extensions that a remote operator may
be permitted to add to an on-line password: R, C, or F. A password
stored with password cell qualifier Fn=0 will not accept any callback
extension. An answering modem will terminate the call if it receives an
Fn=0 password with a callback extension attached.
The roving callback extension (,R) causes the answering modem to
prompt the caller for a telephone number to use for the callback. Once
the number is supplied, the answering modem disconnects the original
call and places a return call using the number it has just been given. The
password to which the roving callback extension is attached must have
been stored in the answering modem with the appropriate password
cell qualifier, Fn=1 or Fn=3.
054R207-000
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3-21
The memory cell callback extension (,C) causes the answering modem
to prompt the caller for the number (0 - 9) of a phone number memory
cell in the answering modem. Once the cell number is supplied, the
answering modem disconnects the original call and places a return call
using the telephone number stored in the specified memory cell. There
are two conditions on the use of the memory cell callback extension:
•
•
Note
It is valid only when the answering modem is not connected to an
MMS controller.
The password to which the memory cell callback extension is
attached must have been stored in the answering modem with the
appropriate password cell qualifier, Fn=2 or Fn=3.
A telephone number stored for callback use should always
include the :n (retry) modifier. Specify that the modem will
make at least three attempts to dial the number. Retries
compensate for any delay in receiving dialtone from the
Central Office after termination of the initial connection.
The fixed callback extension (,F) is only valid when the answering
modem is connected to an MMS controller. It causes the answering
modem to disconnect the original call and place a return call using a
number stored in the controller. Callback numbers are stored in the
controller associated with user names. A user name has to be supplied
as part of the on-line password procedure when the answering modem
is connected to an MMS controller. This extension is not enabled by an
Fn qualifier since it is administered by the controller, not the modem.
Communication Operation and AT Commands
This part of the section describes both communication operating procedures for the V.F 28.8/33.6 modem and the AT commands by which
you can implement those procedures. To operate a V.F 28.8/33.6
modem using AT commands, you need to have a computer or terminal
(the DTE) with an EIA/TIA-232-A, EIA/TIA-530-A, or V.35 serial
port. The port enables communication between the DTE and the
modem. If a computer is being used as the DTE, it will also require a
communications software package. If you plan on using error correction or data compression, the software package must support flow
control.
Command Mode and Data Mode
There are two categories of communication between the V.F 28.8/33.6
modem and its DTE: command mode and data mode. In command
mode the DTE communicates with the modem itself to establish
configuration and to initiate functions. In data mode the DTE communicates through the modem over a telephone line to a modem and DTE
at another site.
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The modem's essential functions are the transmission and reception of
data that take place while it is in data mode. The commands given to
the modem while it is in command mode determine how it accomplishes those functions.
Command mode is always asynchronous; data mode can be either
asynchronous or synchronous. The modem can be configured (by the
&M command) for asynchronous operation in both command and data
modes or asynchronous operation in command mode and synchronous
operation in data mode.
The modem is initially in command mode when it is powered On. It
enters data mode when you command it to go on-line to another
modem (by dialing a switched network connection or initiating
handshake for a private line connection) or when it goes on-line in
response to a connection initiated by a remote modem.
Depending on its option settings, you can cause the V.F 28.8/33.6
modem to enter command mode and wait for the next AT command by
using &D1, dropping DTR, or typing the Escape sequence (+++).
AT Command Mode
In command mode the modem looks at everything you type on the DTE
keyboard, checking constantly for a valid command (AT commands
are described below, and Chapter 4, AT Command Set Operation
contains a complete list of available AT commands). When the modem
detects a valid command, it will execute that command for you. In AT
Command Mode, you may ask the V.F 28.8/33.6 modem to answer a
call, hang up or dial, change an S-Register value, or perform other
command functions.
Some, but not all, AT commands can be issued from the modem's front
panel. Front panel operation is described elsewhere in this section.
Configuration Profiles
A configuration profile consists of the set of AT commands the modem
is given to establish its operating characteristics. The V.F 28.8/33.6
modem can store up to eight configuration profiles: four factoryprovided fixed profiles and four user defined profiles. By recalling and
loading a stored profile you can completely re-configure the modem
without having to change individual options.
The individual profiles in each of the two sets are identified as 0 - 3.
The command to recall and load a fixed profile is &Fn. The description
of the &Fn command in Chapter 4, AT Command Set Operation lists
the characteristics of the four fixed profiles.
The command to recall and load a user defined profile is Zn. The
command to store a user defined profile is &Wn. When it receives the
&Wn command, the modem stores the configuration options in effect
at that time as user defined profile n.
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Each time its power is turned On the modem recalls and loads a user
defined profile. You specify which of the four user defined profiles it
will use for that purpose by means of the Power Up User Configuration
Profile command, &Yn. When the modem leaves the factory the initial
default setting for &Yn is user defined profile 0. The factory default for
user profile 0 is the same as fixed profile 0.
Command Syntax
An AT command takes the form of a single letter or a combination of
a letter and a modifier character, often followed by one or more
numeric characters. The modem interprets the AT command as a
direction to set a configuration parameter or perform an action. The
command (letter or letter and modifier) identifies the parameter or
action, and the numeric value specifies (from a pre-established range of
choices) how the parameter is to be set or how the action is to be
performed. Some AT commands, such as those used to program
telephone numbers, involve further modification through the use of an
equal sign (=) followed by additional numeric characters.
Note
There is one exception to the rule that an AT command is a
letter or a letter/modifier combination: the command for
displaying basic AT command set help is $. It can also be
combined with any of the valid modifiers to display help for
the extended AT command sets.
You send AT commands to the modem in the form of a "command
line." Each command line is preceded by the letters AT or at, contains
one or more commands, and ends with a carriage return. The letters AT
stand for "ATtention" and signal the modem that a command (or
commands) will follow. The modem determines the asynchronous data
rate and parity settings of the local DTE from the command line's AT
prefix.
The A/ command is the one exception that does not require the AT
command line prefix. It is discussed below under the Command Buffer
heading.
It is possible to enter multiple commands on a single line, up to a
maximum of 40 characters. The commands may be separated by space
or line feed characters to improve readability. The modem will ignore
space and line feed characters, so they do not count as part of the line's
40 characters. A carriage-return character must be entered at the end of
a command line to signal the modem to process the commands.
While entering a command line you can correct mistakes by using the
backspace, or Ctrl-H, character. It moves the cursor one character to the
left and deletes the character. The AT prefix cannot be deleted.
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Command Buffer
When the command line is sent to the modem, it is loaded into a
command buffer with a capacity of 40 characters. The AT prefix,
spaces, line feed characters, and carriage return are not loaded into the
buffer, and so do not count as part of the 40-character limit. If a
command line is more than 40 characters long, the modem will only act
on commands that are contained in the first 40 characters.
The A/ command instructs the modem to re-execute the command line
currently in the buffer. It is to be sent to the modem as a command line
that consists of only the A/ command and a carriage return - no AT
prefix. This is the only command line that does not need to be preceded
by the AT prefix.
Automatic DTE Speed and Parity Detection
In command mode the modem automatically detects the DTE's
operating speed and asynchronous character parity when it receives the
AT prefix from the DTE.
The modem can automatically adapt to incoming data at any of the
following asynchronous bit rates:
128,000 bps
115,200 bps
112,000 bps
96,000 bps
76,800 bps
72,000 bps
64,000 bps
57,600 bps
56,000 bps
48,000 bps
38,400 bps
32,000 bps
32,000 bps
31,200 bps
28,800 bps
26,400 bps
24,000 bps
21,600 bps
19,200 bps
16,800 bps
14,400 bps
12,000 bps
9600 bps
7200 bps
4800 bps
2400 bps
1200 bps
300 bps
Note
Configuration via the &H command determines what
modulation the modem will operate with at a DTE speed of
1200 or 300 bps. At 1200 bps the modem can be configured
to use either ITU-T V.22 or Bell 212A modulation. At 300
bps the modem can be configured to use either ITU-T V.21
or Bell 103 modulation.
The modem can automatically adapt to the character length and parity
of the characters coming from the DTE. It adapts to ODD, EVEN,
SPACE, or MARK/NONE parity.
The automatic detection and adaptation function works for either lower
case "at" or upper case "AT". Mixed cases ("At" or "aT") will not give
predictable results.
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Remote Configuration Using the AT Commands
Remote Configuration allows you to use a local V.F 28.8/33.6 modem
to connect to a remote V.F 28.8/33.6 modem and view or change the
remote modem's current user configuration profile.
Before you initiate a Remote Configuration session, you must ensure
the following:
•
•
•
•
•
•
Note
Modems must either both be in switched network mode or both be
in private line mode.
The local modem must be in AT command mode (%V0 or PRS
AT command). The remote modem will be forced into AT
command mode when the connection is established.
The local modem must be in an asynchronous error correcting
mode. The remote modem will be forced into asynchronous mode
when the connection is established.
Both modems must have the same remote configuration security
password (*Pn command). If the remote modem does not have a
remote configuration security password, you may configure one
during the Remote Configuration session.
The remote modem's handshake mode must be V.34 (&H0, &H1,
or &P0 command), V.32 bis (&H2, &H3, or &P1 command), or
V.32 (&H4, &H5, or &P2 command).
If you intend to save changes, you must enable remote
configuration write access (*R0 command) at the remote modem
before initiating the session.
a.
b.
The DTE interface on the remote modem is disabled
during the Remote Configuration session to prevent
the remote DTE from inadvertently terminating the
session.
Responses and echoes from the remote to the local
modem are enabled regardless of the optioning of the
remote modem. If quiet mode is selected on the remote
modem, it will still send echo back to the local modem.
To initiate a Remote Configuration session, enter *W1 at the local
modem. In private line mode, the connection is made automatically. In
switched network mode, you must place the call to the remote modem.
Upon connection, the local modem displays
OK REMOTE CONFIG SESSION VIEW
if Remote Configuration write access is disabled, or
OK REMOTE CONFIG SESSION EDIT
if Remote Configuration write access is enabled.
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After you establish a Remote Configuration session, you may view or
edit (change) the remote modem's current user configuration profile in
the same way you would the local modem's. The changes that you
make do not affect the modem as you make them. Instead, they become
part of a configuration profile. Once you have made all the changes you
intend to, you have the following options:
•
To terminate the session without saving or using the new
configuration profile, enter *X0.
•
To terminate the session and put the new configuration profile into
use temporarily (i.e., modem will use the new configuration only
until it is reset or power is cycled), enter *X1.
•
To save the new configuration as a user defined profile that can be
recalled and loaded in the future, use the &Wn command before
entering *X1 to terminate the session and put the new
configuration into use.
The following commands are invalid during a Remote Configuration
session and will cause an error response:
•
•
•
•
•
A (answer call)
Dn (dial)
Hn (hookswitch)
On (on-line)
&Tn (test mode), except &T4 and &T5
Data Mode
The V.F 28.8/33.6 modem is in data mode while it has a telephone line
connection to another modem or is in the process of establishing a
connection. In Data Mode the modem transmits all the data it receives
from the DTE over the phone line.
In data mode the modem can operate either asynchronously or synchronously, as specified by the &M command. A variety of data protocols
are available for each type of operation. Some protocols provide error
correction to improve reliability and/or data compression to increase
throughput. The two types of data mode operation, and their protocols,
are described at length in the following pages.
Each telephone line connection (whether switched network or private
line) between two modems in data mode begins with a handshaking
sequence. During that sequence the modems determine the VF (telephone line) speed, data protocol, and related parameters for the data
link. Configuration determines the range of choices available to the
modem in the negotiation process. Most configuration options in the
V.F 28.8/33.6 modem act to limit the range over which a parameter can
be negotiated, rather than making specific assignments.
The modem's DTE can cause it to enter data mode and initiate dialing
(switched network) or handshaking (private line) by asserting the Data
Terminal Ready (DTR) signal at the interface or by issuing an AT
command to dial. Configuration determines whether or not the modem
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is controlled by DTR. The presence of a carrier from a remote modem
will cause the V.F 28.8/33.6 modem to enter data mode and assert a
Data Carrier Detect (DCD) signal to its DTE.
Asynchronous Operation
When you select Operating Mode 0 (&M0) the V.F 28.8/33.6 modem
will operate asynchronously both while on-line (data mode - connected
to the telephone line) and while off-line (Command Mode - disconnected from the telephone line).
The V.F 28.8/33.6 modem can employ error correction (reliable)
protocols to ensure error-free delivery of asynchronous data sent
between computers. The error control methods are based on grouping
data into frames with checksums determined by the contents of each
frame. The receiving modem checks the frames and sends acknowledgments to the transmitting modem. When it detects a faulty frame, the
receiving modem requests a re-transmission. Frame length varies
according to the amount of data transmitted or the number of re-transmissions requested from the DTE.
The modem can achieve DTE speeds greater than the maximum VF
speed through the use of a data compression protocol. The asynchronous compression protocol available is the V.F 28.8/33.6: ITU-T V.42
bis. It attempts to increase throughput by compressing the information
to be sent before actually sending it. The modem is thus able to transmit
more data in a given period of time. Characteristics of the individual
compression technique are discussed below.
The V.F 28.8/33.6 supports the following asynchronous DTE speeds:
128,000 bps
115,200 bps
112,000 bps
96,000 bps
76,800 bps
72,000 bps
64,000 bps
57,600 bps
56,000 bps
48,000 bps
38,400 bps
32,000 bps
28,800 bps
26,400 bps
24,000 bps
21,600 bps
19,200 bps
16,800 bps
14,400 bps
12,000 bps
9600 bps
7200 bps
4800 bps
2400 bps
1200 bps
300 bps
The V.F 28.8/33.6 supports the following VF data speeds:
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33,600 bps
31,200 bps
28,800 bps
26,400 bps
24,000 bps
21,600 bps
19,200 bps
16,800 bps
14,400 bps
12,000 bps
9600 bps
7200 bps
4800 bps
2400 bps
1200 bps
300 bps
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Error Correcting Modes
The V.F 28.8/33.6 modem can employ the following error correcting
mode:
•
V.42 (LAPM) reliable
The \N command selects the modem's error correcting mode. The
modem interprets \N in combination with the %C command to
determine what data compression protocol (if any) is available. Table
3-3 shows the combinations of those commands that achieve the
various available modes. The full characteristics of each command are
described in Chapter 4, AT Command Set Operation .
Each mode has specific features that impact how the modem will
function. One major distinction between the standard modem state and
the error correction modem state is that bi-directional data buffering
and flow control are required for error correction. Buffering and flow
control allow the modem to operate with the computer serial port and
the modem port set for different data rates. Flow control is discussed
following the descriptions of the error correcting and compression
protocols.
V.42 (LAPM) Reliable Mode Error Correction
The V.42 (LAPM) reliable error correction mode first looks for the
LAPM character during the handshake. The modem transmits a Link
Access Protocol (LAPM) character as part of the handshake when it
attempts to negotiate a V.42 link. The V.42 protocol provides error
correction compliant with the ITU-T V.42 error correction scheme and
supports the ITU-T V.42 bis data compression algorithm.
Due to increased complexities during the handshaking procedures, the
V.42 (LAPM) reliable mode is recommended for use only with other
V.42 modems when data integrity is critical.
Non-Error Correcting Modes
The V.F 28.8/33.6 modem also employs the following non-error
correcting modes:
•
wire mode
•
direct V.14 asynchronous mode
•
V.13 mode
These modes are configured using the \N command. Chapter 4, AT
Command Set Operation contains full description of the options for
that command.
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Wire Mode
Wire mode (\N0) is used to communicate with standard, non-error
correcting modems. The V.F 28.8/33.6 will fall back to wire mode if it
fails in an attempt to negotiate an auto-reliable link with the remote
modem. Error correction is not active in wire mode.
Wire mode provides data buffering so that the modem's DTE and VF
interfaces can operate at different speeds. For example, the local DTE
can exchange data with the local modem at 19,200 bps while the
modem communicates at 2400 bps with the remote modem. To do this,
however, the local terminal emulation software must allow its autobaud
feature to be turned off and allow flow control.
Direct V.14 Asynchronous Mode
In direct V.14 mode (\N1) there is no error correction, data compression, or data buffering. The modem's DTE data rate and VF line speed
must be set to the same value. If, for example, the link between the V.F
28.8/33.6 and the remote modem operates at 9600 bps, then the local
DTE must exchange data with the V.F 28.8/33.6 at 9600 bps.
V.13 Mode
V.13 mode (\N1) is a simulated controlled carrier mode designed for
polling applications. It uses the ITU-T V.13 RTS/DCD signaling
method to control the remote modem's DCD lead via the local modem's
RTS lead. It can be used for both synchronous and asynchronous data.
The RTS/DCD signaling can be configured for either bi-directional or
unidirectional control by the &E command.
Flow Control
The V.F 28.8/33.6 modem supports flow control. In combination with
internal data buffering flow control permits portions of a data link to
operate at different speeds. For example, the rate of transfer between
the local DTE and modem can be greater than the VF line speed negotiated between the local and remote modems, while the modem-to-DTE
transfer rate at the remote site can differ from both. The modems'
buffers compensate for such differences to a large degree, but flow
control comes into play when data traffic approaches the limits of
buffer capacity. Flow control meters incoming data and can stop it from
coming in when there is not enough room available in the modem's
internal buffer. Without flow control, data will be lost if the modem
port and the VF line interface don't operate at the same bps rate.
Error correction and data compression are both sources of the rate
differences that flow control and buffering compensate for.
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Flow control can be achieved either by software or by hardware.
Software flow control involves control characters inserted within the
transmitted data. Hardware flow control is achieved by altering the
voltage level of various signal lines at the interface between the
computer's serial port and the modem. The V.F 28.8/33.6 supports
three forms of hardware flow control: one (described below) that is
compatible with asynchronous operation, and two that are only for use
with synchronous data compression.
Software Flow Control
Software flow control uses the XON and XOFF characters, which are
also known as Control-Q and Control-S, respectively. The characters
are inserted in the transferred data.
Use of XON/XOFF software flow control requires care to make sure
that only the desired element in the system responds to the flow control
characters. If you are using XON/XOFF to control the local serial port,
you may not want the flow control characters to be passed along to the
remote modem with the data.
The \G command is used to determine whether the V.F 28.8/33.6
processes the flow control characters and passes them to the remote
modem along with the data, or simply processes them and deletes them
from the data stream.
Hardware Flow Control
Hardware flow control can be either unidirectional or bi-directional.
Exactly how you set the flow control commands depends on your
application. Bi-directional hardware flow control is recommended if
your application demands both file uploads and downloads and the
transfer protocol does not support any form of XON/XOFF.
Hardware flow control for asynchronous operation usually uses the
signals RTS (request to send) and CTS (clear to send). Study the
commands \G and \Q in the Extended AT Command Set in Chapter 4,
AT Command Set Operation for further information on this topic. In
MNP Reliable Mode or V.42 Mode the protocol itself controls data
flow on the modem port. Retransmissions due to a very noisy phone
line may cause the buffer to fill, however, so the use of flow control on
the serial port is still important.
Table 3-14 lists the AT commands used to enable the different types of
data compression and error correction.
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Table 3-14
Enabling Error Correction/Data Compression
To Enable
Use AT Commands
V.42 Auto Reliable
V.42 bis
Wire
\N3 and %C1
V.42 (LAPM) and V.42 bis only
\N4 and %C1
V.42 only
\N4 and %C0
V.42, V.42 bis or MNP 2-5 only
\N5 and %C1
No data compression and no
error correction
\N0 or \N1, and %C0
Synchronous Operation
Synchronous Operating Modes
The &Mn (Operating Mode) command selects between asynchronous
and synchronous Data Mode operation. Its synchronous mode setting,
&M1, supports asynchronous dialing with synchronous transmission.
Each synchronous operating mode is detailed on the following pages.
Following the descriptions of the dialing/data transmission modes the
manual describes the three available synchronous protocols. The \Mn
command selects the protocol that the modem will follow while it is in
synchronous Data Mode.
In addition, the V.F 28.8/33.6 modem can be configured for synchronous operation by selecting one of the above synchronous operating
modes from the front panel.
Asynchronous Dialing with Synchronous Transmission
The &M1 mode, Asynchronous Dialing with Synchronous Transmission, supports DTE that are capable of communicating synchronously
or asynchronously over the same RS-232 port.
Your call is placed using the asynchronous command set. Once the call
connection is established, the V.F 28.8/33.6 modem will automatically
switch to synchronous operation.
The &M1 mode also permits you to use an asynchronous DTE to dial
and then switch to a synchronous-only DTE once the call is connected.
If the &D setting is other than &D0, the S25 register will determine the
length of time permitted to switch DTE before the call is disconnected.
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Direct Dialing in Synchronous Mode
Direct dialing in synchronous data mode can be accomplished in either
of two ways:
•
DTR dialing, selected by %Zn
•
V.25 bis commands
When DTR dialing is enabled (%Z1), the V.F 28.8/33.6 modem will
automatically dial the previously stored number (stored using the
&Zn=nnn command) when it detects an OFF to ON transition on DTR.
If you wish to save this profile, issue the &W command. The modem
will then come up in this mode any time power is applied.
Note
Once DTR dialing has been selected, you may find that the
modem goes off-hook and begins dialing the stored number
the moment you connect your DTE. To prevent this, turn off
your modem before you connect the DTE to the modem.
When the connection is complete, turn the modem back on.
The V.25 bis command set is described in detail in Chapter 5, V.25 bis
Command Set Operation .
Normal Synchronous Mode
The \M0 command selects the Synchronous Protocol for normal
synchronous operation. The modem employs a constant carrier on the
VF line. The DTE-to-VF speed relationship is direct, that is the two
speeds must match.
The following DTE data rates are available (\Tn command) when the
modem operates in normal synchronous mode:
28,800 bps
26,400 bps
24,000 bps
21,600 bps
19,200 bps
16,800 bps
14,400 bps
12,000 bps
9600 bps
7200 bps
4800 bps
2400 bps
1200 bps
300 bps
V.13 Synchronous Mode
The \M1 command selects the Synchronous V.13 Protocol. V.13 mode
is a simulated controlled carrier mode designed for polling applications. It uses the ITU-T V.13 RTS/DCD signaling method to control
the remote modem's DCD lead via the local modem's RTS lead.
The RTS/DCD signaling can be configured for either bi-directional or
unidirectional control by the &E command.
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The following DTE data rates are available (\Tn command) when the
modem operates in V.13 synchronous mode:
28,800 bps
26,400 bps
24,000 bps
21,600 bps
19,200 bps
16,800 bps
14,400 bps
12,000 bps
9600 bps
7200 bps
4800 bps
2400 bps
1200 bps
300 bps
Synchronous Compression Mode
The \M2 command selects the Synchronous Compression Protocol.
The modem can compress synchronous DTE data framed in HDLC/
SDLC format, with a maximum frame length of 2048 bytes.
Note
Synchronous Compression is an optional feature that is not
included in all V.F 28.8/33.6 modems. To check the
presence of the feature in your modem, use AT command I5
to display a list of information concerning the modem. Sync
Compression On/Off is included in that list.
Synchronous compression supports the following DTE data rates (\Tn
command):
128,000 bps
115,200 bps
112,000 bps
96,000 bps
76,800 bps
72,000 bps
64,000 bps
57,600 bps
56,000 bps
48,000 bps
38,400 bps
32,000 bps
28,800 bps
26,400 bps
24,000 bps
21,600 bps
19,200 bps
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Two techniques for modem-to-DTE hardware flow control are
available for use with synchronous compression. Both require that the
modem be configured for internal timing (see below). Flow control for
synchronous compression can be accomplished by:
•
•
Clock Stopping (\Q5) in which the modem prevents buffer
overflow by sharply reducing the frequency of the transmit clock
signal it outputs to the DTE.
Clock Throttling (\Q6) in which the modem prevents buffer
overflow by varying the rate at which it outputs the transmit clock
signal to the DTE.
Clock Selection
The synchronous format relies on transmit and receive clocks to
maintain character timing. It therefore does not need start and stop bits
for each character as does the asynchronous format. The V.F 28.8/33.6
modem can be configured to use one of the following three clock
sources to transmit synchronous data:
•
Internal (&X0) - transmit clock generated by the V.F 28.8/33.6
modem.
•
External (&X1) - transmit clock signal generated by the DTE is
passed to the modem along with data.
•
Receiver (&X2) - transmit clock derived by the local modem from
the data it is receiving from the remote modem (also called wrap
timing).
The preferred clock source varies for different computer systems.
Consult your computer's manual for its particular specifications.
Regardless of which transmit clock source it is using, the V.F 28.8/33.6
modem always outputs its transmit clock signal to the DTE on pin 15
of the EIA interface. Pin 17 always provides the receive clock signal
derived from the incoming data. When the DTE provides external
transmit clock it does so on Pin 24.
Note
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The receive clock is always controlled by the remote
modem that sends the data being received. It is not
recommended to have the local and remote modems both
configured to derive transmit clock from received data.
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Switched Network Operation
To establish a connection with another modem, you use the auto-dial
facility of the V.F 28.8/33.6 modem.
Telephone Lines
To achieve optimum throughput with the V.F 28.8/33.6 modem it is
advisable to connect it to a single switched line, that only it uses. If it
is connected to a business telephone system, such as a multi-line key
system or PBX, there can be noise generated by the system that can
affect telephone quality.
Many telephone companies offer "call waiting" service that alerts you
to another call coming in while you are on the line. Call waiting service
can interfere with modem data calls or even disconnect the modem. In
error correction mode the modem will correct data interference caused
by call-waiting, but doing so degrades throughput. If you have callwaiting, you should disable it while you are on the line to prevent loss
of through-put. In some areas, for example, you can disable call waiting
by dialing 70# or *70 on your pushbutton telephone. Verify the callwaiting numbers with your local telephone company.
The following are examples of commands to send to the modem to
disable call waiting for the duration of a call (the telephone number
555-1234 is provided for example only):
ATDT*70W5551234
(For Touch-Tone Dialing)
ATD1170W5551234
(For Both Pulse and Touch-Tone Dialing)
Note
After the *70 or 1170 number is dialed, your PSTN should
respond with dial tone. The call you then dial will have the
call-waiting feature disabled for its duration. Once the call
is disconnected, the call-waiting feature will re-enable
itself. Verify the numbers and their effects with your local
telephone company.
Another method is to set your modem to S10=150. This setting lets
your modem ignore a brief cut-off caused by call-waiting, and prevents
it from hanging up while on-line.
Private Line Operation
Besides being able to operate over the public switched telephone
network, the V.F 28.8/33.6 modem can be configured to operate over a
point-to-point, unconditioned, voice grade private line (speech band
leased line).
3-36
V.F 28.8/33.6 ModemDeskTop Platform
Installation and Operation
054R207-000
Issue 11
Point-to-point private lines rented from the telephone company are
dedicated, direct, semi-permanent phone line connections between two
locations. In applications that require a continuous data transfer
between fixed points, it may be more economical to rent a private line
at a fixed rate, than to pay monthly long distance charges for dial up
calls. The communication link between two multiplexers will generally
involve a modem operating over private lines.
Note
Speeds below V.32 4800 bps are not supported in private
line operation.
Two-wire or Four-wire Selection
The V.F 28.8/33.6 modem is capable of operation on private line
networks, using either 4-wire or 2-wire circuits. Use &L1 to select 2wire operation or &L2 to select 4-wire operation.
Note
a.
b.
c.
For proper private line connection, the 8-pin cable
should be used to connect the modem's jack marked PL
to the JM8 wall outlet supplied by your service
provider.
It is recommended that the front panel be used to set
and store the transmit levels. Before using the AT
command to set/store the transmit levels, verify that
the correct value is entered using the front panel
display.
When using Factory Default 0 (&F0) to set up a
private line connection, make all other option settings
before issuing the &L1 or &L2 command. The modem
will begin its training sequence at once when it is
given the &L command. (To abort training sequence
and return to Command mode you can either press the
SEL button three times or press the AL button.
Other Configuration
Configuring the V.F 28.8/33.6 for private line operation is very simple.
In any private line connection, first designate one modem as the
originate modem (%O0) and the other as the answer modem (%O1).
Next, configure both modems for the type of communication they are
intended to perform: these include normal or reliable modes (\N
command), synchronous or asynchronous modes (&M command),
DTE and VF speeds (\T and &P commands), etc. Select &P0 (V.34
only), &P1 (V.32 bis only) or &P2 (V.32 only) to establish the desired
modulation in private line.
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V.F 28.8/33.6 Modem DeskTop Platform
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3-37
It is also possible to configure the modem for private line operation as
above from the front panel.
Transmit Level
It is possible in private line operation for the transmit levels of the
modems to be either too low or too high. When that is the case the
connection usually will not be dependable and will be filled with errors.
To correct such situations, the transmit level of the V.F 28.8/33.6 for
private line operation can be configured in 1 dBm increments between
0 dBm and -15 dBm. This selection can be done either from the front
panel or with the :T command. See Chapter 4, AT Command Set
Operation for details.
Note
It is recommended that you permanently store the above
settings either by entering the &W command, or by using
the front panel and saving the entry. The modems are now
ready for private line communications.
Automatic and Manual Handshaking
The V.F 28.8/33.6 modems utilize a private line "idle" mode to facilitate the use of the AT command set for private line set up. The modems
can be put into private line idle via the front panel talk/data switch (SEL
key), AT command H, or the MMS command Private Line Talk/Data.
If the modems are already trained and option changes are desired, a
"+++" sequence can be used to enter command mode. After the
changes are complete, an O command can be used to go back on line or
an H command can be issued to go to idle. From idle, either the talk/
data switch or O can be used to initiate a new connection. Once told to
handshake, the modems will continuously try to complete a handshake.
When this process is complete, the modem will display a CONNECT
message on the DTE.
When communicating with a different modem in private line operations, the following steps outline how to configure the modems:
3-38
1.
Configure both modems for the type of communications
they are intended to perform.
2.
Configure the V.F 28.8/33.6 modem as the ORIGINATE
modem, using the %O0 command.
3.
Again, use the &W command to permanently store the
current configurations for both modems.
V.F 28.8/33.6 ModemDeskTop Platform
Installation and Operation
054R207-000
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Auto Dial Restoral
Auto Dial Restoral (ADR) allows the V.F 28.8/33.6 modem to attempt
automatic restoration of the data link over a switched network line if
the private line fails.
When the originate modem goes into a retrain (because of poor signal
quality or a line interruption), the private line down timer (S-Register
40) is activated. The modem will continue retrains until successful or
until the timer expires. When a retrain is successful, the timer is reset.
If the timer expires before there is a successful retrain, the modem will
attempt a switched network connection by dialing the number stored in
cell 0. (This number may have dial modifiers to link to another cell or
redial as many times as desired.) The modem stays in switched network
mode until the lookback function returns it to private line mode or until
you manually disconnect the call. If the modem cannot establish the
switched network connection, it reverts to private line mode and starts
the process over.
The originate modem's private line lookback timer (S-Register 41)
determines how long the modem will operate on the switched network
connection before it tries to return to private line mode. When the
private line lookback timer expires, the modem will attempt a private
line handshake. When the private line connection is made, the modem
will drop the switched network call. If the private line connection
cannot be made, the modem will reset the timer and try again when the
timer expires. (If the timer is disabled, the modem makes no attempts
to return to the private line.)
There are two configurations for Auto Dial Restoral: restore the data
link with a switched network connection to the same modem used in
private line mode, or restore the data link with a switched network
connection to a different modem (usually one in a modem pool).
Note
Character Abort should be disabled (Command %K1) in
modems that will perform Auto Dial Restoral. If this is not
done, data on the modem's interface leads can cause
dialing to abort.
To restore the data link with a switched network connection to the same
modem, you must ensure the following:
•
•
Both modems (originate and answer) must have Auto Dial
Restoral enabled (&Bn command). Use &B2 when dial restoral is
expected to appear as a retrain. This is typical when the modem
being dialed is the one on the answer end of the failed private line.
Cell 0 of the originate modem must contain the phone number of
the answer modem.
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V.F 28.8/33.6 Modem DeskTop Platform
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3-39
•
The private line down timer for the originate modem must be
enabled (S-Register 40 must be non-zero).
•
Automatic answer for the answer modem must be enabled
(S-Register 0 must be non-zero).
•
The private line answer modem must be in a retrain or be idle to
be able to answer a call.
To restore the data link with a switched network connection to a
different modem, you must ensure the following:
•
•
•
•
The originate modem must have Auto Dial Restoral enabled (&Bn
command). Use &B1 when a line failure indication is required at
the DTE (the DSR, CD and CTS signals operate according to their
options between dial restoral and successful lookback operations).
This is typical when the dial-back answer modem is in a modem
pool.
Cell 0 of the originate modem must contain the phone number of
the answer modem.
The private line down timer for the originate modem must be
enabled (S-Register 40 must be non-zero).
The answer modem can be any compatible switched network
modem.
Testing The Modem
Chapter 6, Tests describes basic diagnostics. Tests performed with the
modem in asynchronous mode do not use error control. Consequently,
by making the remote loop test during an error control connection, the
error control mode is terminated and transmission errors caused by the
transmission link can be detected.
3-40
V.F 28.8/33.6 ModemDeskTop Platform
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054R207-000
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Chapter 4: AT Command Set
Operation
Overview
This section describes the V.F 28.8/33.6 modem's AT (attention)
command set. The complete AT command set includes the basic AT
and extended AT&, AT%, AT\, AT: and AT* command sets.
This section includes several tables listing the AT commands. They
group the commands as follows:
•
By option name (Table 4-1) - Use this table if you know the name
of an option and need to find out what its AT command is and on
which page it is described.
•
By the type of function (Table 4-2) - Use this table to find out
which options apply to terminal configuration or diagnostics, for
example. It closely follows the structure seen when using the front
panel.
•
By command set (Table 4-3) - Use this table when you know that
what you're looking for is an AT& command, for example, but you
can't remember if it's &Cn or &Dn.
The above tables list only the name and command. To quickly see the
choices available for each command, use Table 4-4 throughTable 4-9.
They provide a brief description of all of the choices for each
command. Each table groups one command set. A detailed command
reference follows these tables.
Commanding The Modem
The V.F 28.8/33.6 supports the AT command protocol that permits you
to:
•
Obtain information from the modem
•
Configure the modem
•
Establish data communications
•
Test the modem and data communications system
After the modem is installed and/or powered up, it is in the command
mode and will accept commands from the terminal. Each command
(except A/) must be preceded by the letters AT and followed by a
carriage return or enter (enter). A/ is used to repeat the last command
without entering the AT-prefix. When AT is entered, the modem
detects the data rate and parity used by the terminal and begins
operating at that same data rate and parity until it gets changed.
054R207-000
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V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-1
Note
Special Considerations in Asynchronous Operation
The V.F 28.8/33.6 modem is shipped from the factory with the
data terminal (DTE) interface set for 7 bits with parity, at the last
AT speed. This determines the modem's DTE speed when auto
answering. If no commands are entered, to change and store a
new default, set your terminal/communication program to the
desired speed, data length and parity. Then type "AT&W." This
stores the DTE interface parameters. These parameters remain
until an AT command is entered which will change the modem's
DTE speed from the stored values.
Up to 40 command characters may be entered. AT commands that
exceed 40 characters will not be executed. The AT prefix, space,
carriage return and line feed characters are ignored by the modem, and
therefore do not count as part of the command line. A carriage-return
character must be entered at the end of the command line, otherwise the
command will not be processed. Mistakes may be corrected by typing
the backspace character. This will move the cursor over the character
to be corrected. The AT prefix cannot be deleted.
After each command is entered, the modem responds by sending a
result code back to the terminal. Unless the result code function is
disabled or the communications software being run on a computer
emulating a terminal ignores result codes, the code is displayed by the
terminal to indicate the result of the entered command. Valid
commands return OK; invalid commands return ERROR.
New commands can not be issued until a response to the previous
command is received. If there is no response, a wait of three character
times is required before the next command. If the DTE rate is changed
then 1 second must elapse.
Setup Procedures
4-2
1.
Install the V.F 28.8/33.6 modem as described in Chapter 2,
Installation .
2.
Select the proper communications port on the terminal or
terminal emulator program and ensure 10 bit ASCII is selected.
3.
If a communications software package is being used, it will
interface with the modem and no further setup is required. Refer
to the documentation for the communication software package.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
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4.
If the modem is being used interactively on a terminal or with a
terminal emulation package, issue AT$ (enter). If the V.F 28.8/
33.6 is connected properly, it will respond to the command by
displaying the basic AT command set help menu.
5.
Use the commands in this section to configure and operate the
V.F 28.8/33.6 as required.
Table 4-1
AT Commands Listed by Name
Name
Adjustable transmit level display
Answer call
Cmd.
Page
S100?
4-48
A
4-25
%On
4-39
Asynchronous protocol
\Nn
4-38
AT command set help
$
4-24
AT% command set help
%$
4-24
AT& command set help
&$
4-24
AT: command set help
:$
4-24
AT\ command set help
\$
4-24
Answer mode
AT* command set help
*$
4-24
&Bn
4-26
Auto-reliable fallback character
%An
4-25
Automatic answer
S0=x
4-45
Automatic fallforward/fallback
&An
4-25
Backspace character
S5=x
4-45
Break character handling
\Kn
4-37
Call Progress Monitor
Xn
4-56
Call Progress Monitor message response speed
%Rn
4-42
Carriage return character
S3=x
4-45
Carrier loss timer
S10=x
4-46
Carrier presence timer
S9=x
4-46
Carrier, dial and ringback wait timer
S7=x
4-45
Character abort
%Kn
4-36
Character length
\Bn
4-26
Command format
%Vn
4-52
\Vn
4-52
Auto Dial Restoral
Connect message type
(Sheet 1 of 4)
054R207-000
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V.F 28.8/33.6 Modem DeskTop Platform
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4-3
Table 4-1
AT Commands Listed by Name (Continued)
Name
Cmd.
Page
N?
4-38
CTS operation
&Rn
4-41
Data compression
%Cn
4-27
DCD operation
&Cn
4-26
DCE rate limit
&Gn
4-34
Country code
Dn
4-28
Dial pause timer
S8=x
4-46
Dial tone wait timer
S6=x
4-45
P, T
4-39, 4-49
DSR operation
&Sn
4-48
DSR operation in test mode
%Dn
4-29
DTE interface-controlled tests
%En
4-29
\Tn
4-50
S25=x
4-47
%Zn
4-58
DTR On-to-Off transition
&Dn
4-29
Escape code character
S2=x
4-45
Escape code guard timer
S12=x
4-46
\Cn
4-27
Dial
Dialing type
DTE speed
DTR delay timer
DTR dialing
Fallback selection and pre-link data buffer
Front panel lockout
General security password
Hang-up delay timer
Hookswitch
&In
4-36
%Pn
4-40
S38=x
4-47
Hn
4-35
In
4-36
Line feed character
S4=x
4-45
Load fixed configuration profile
&Fn
4-30
Load user configuration profile
Zn
4-57
Local DTE echo
En
4-29
Long space disconnect
Yn
4-57
Make busy
%Bn
4-26
Modem-to-DTE flow control
\Qn
4-41
Modem-to-modem flow control
\Gn
4-34
Identification and checksum
(Sheet 2 of 4)
4-4
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
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Table 4-1
AT Commands Listed by Name (Continued)
Name
Network type
Cmd.
Page
&Ln
4-37
On
4-39
Operating mode
&Mn
4-38
Overspeed correction
\An
4-25
Parity type
\Pn
4-40
Password cell qualifier
%Fn
4-33
Password operation
%Sn
4-49
On-line
Power-up user configuration profile
Private line down timer
&Yn
4-57
S40=x
4-47
&Pn
4-39
S41=x
4-48
Private line transmit level
:Tn
4-51
Remote configuration control
*Wn
4-56
Remote configuration exit
*Xn
4-57
Remote configuration security password
*Pn
4-40
Remote configuration write access
Private line handshake mode
Private line lookback timer
*Rn
4-43
Repeat command
A/
4-26
Response mode
Qn
4-40
Result code type
Vn
4-52
%Qn
4-40
S70=x
4-48
Ring counter
S1=x
4-45
RTS-to-CTS delay timer
S26=x
4-47
S-Register help
S$
4-25, 4-43
S-Registers
Sn
4-43
Save settings as a user configuration profile
&Wn
4-56
Simulated controlled carrier
&En
4-29
Speaker operation
Mn
4-37
Speaker volume
Ln
4-37
Store a phone number
&Zn=nnn
4-58
Store password
%Pn=nnn
4-40
&Hn
4-35
Retrain on poor signal quality
Retransmission counter
Switched network handshake mode
(Sheet 3 of 4)
054R207-000
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V.F 28.8/33.6 Modem DeskTop Platform
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4-5
Table 4-1
AT Commands Listed by Name (Continued)
Name
Cmd.
Page
:Pn
4-40
Synchronous protocol
\Mn
4-38
Test mode
&Tn
4-49
Switched network transmit type
S18=x
4-46
Transmit clock source
&Xn
4-56
Trellis coding
&Un
4-51
&V
4-52
Test mode timer
View stored phone numbers
(Sheet 4 of 4)
Table 4-2
AT Commands Listed by Function
Name
Cmd.
AT Command Set Options
AT command set help
$
AT& command set help
&$
AT% command set help
%$
AT\ command set help
\$
AT: command set help
:$
AT* command set help
*$
Repeat command
A/
S-Register help
S$
S-Registers
Sn
Configuration Profile Options
Load fixed configuration profile
&Fn
Load user configuration profile
Zn
Power-up user configuration profile
&Yn
Save settings as a user configuration profile
&Wn
Diagnostics Options
DSR operation in test mode
%Dn
DTE interface-controlled tests
%En
Test mode
&Tn
S18=x
Test mode timer
(Sheet 1 of 4)
4-6
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
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Table 4-2
AT Commands Listed by Function (Continued)
Name
Cmd.
Dialer Options
%Vn
Command format
Dn
Dial
Dial pause timer
S8=x
Dial tone wait timer
S6=x
Dial wait timer
S7=x
Dialing type
P, T
DTR dialing
%Zn
Ringback wait timer
S7=x
Store a phone number
View stored phone numbers
&Zn=nnn
&V
Modem Options
Answer call
A
Automatic answer
S0=x
Carrier loss timer
S10=x
Carrier presence timer
S9=x
Carrier wait timer
S7=x
Country code
N?
Front panel lockout
&In
General security password
%Pn
S38=x
Hang-up delay timer
Hookswitch
Hn
Identification and checksum
In
Long space disconnect
Yn
%Bn
Make busy
On-line
On
Remote configuration control
*Wn
Remote configuration exit
*Xn
Remote configuration security password
*Pn
Remote configuration write access
*Rn
Retransmission counter
S70=x
Ring counter
S1=x
(Sheet 2 of 4)
054R207-000
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4-7
Table 4-2
AT Commands Listed by Function (Continued)
Name
Cmd.
Mn
Speaker operation
Ln
Speaker volume
Transmit clock source
&Xn
Network Options
&Bn
Auto Dial Restoral
&Ln
Network type
Private line down timer
S40=x
Private line lookback timer
S41=x
Private line transmit level
:Tn
Switched network transmit type
:Pn
Protocol Options
%On
Answer mode
Asynchronous protocol
\Nn
Auto-reliable fallback character
%An
Automatic fallforward/fallback
&An
Data compression
%Cn
Modem-to-modem flow control
\Gn
Private line handshake mode
&Pn
Retrain on poor signal quality
%Qn
Simulated controlled carrier
&En
Switched network handshake mode
&Hn
Synchronous protocol
\Mn
Trellis coding
&Un
Terminal (DTE) Options
S5=x
Backspace character
Break character handling
\Kn
Call Progress Monitor
Xn
Call Progress Monitor message response speed
%Rn
Carriage return character
S3=x
Character abort
%Kn
Character length
\Bn
Connect message type
\Vn
(Sheet 3 of 4)
4-8
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
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Table 4-2
AT Commands Listed by Function (Continued)
Name
Cmd.
CTS operation
&Rn
DCD operation
&Cn
DSR operation
&Sn
\Tn
DTE speed
S25=x
DTR delay timer
DTR On-to-Off transition
&Dn
Escape code character
S2=x
Escape code guard timer
S12=x
Line feed character
S4=x
Local DTE echo
En
Modem-to-DTE flow control
\Qn
Operating mode
&Mn
Overspeed correction
\An
Parity type
\Pn
Fallback selection and pre-link data buffer
\Cn
Response mode
Qn
Result code type
Vn
S26=x
RTS-to-CTS delay timer
(Sheet 4 of 4)
Table 4-3
AT Commands Listed by Command Set
Name
Cmd.
Basic AT Command Set
Answer call
A
AT command set help
$
Automatic answer
S0=x
Backspace character
S5=x
Call Progress Monitor
Xn
Carriage return character
S3=x
Carrier loss timer
S10=x
(Sheet 1 of 4)
054R207-000
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4-9
Table 4-3
AT Commands Listed by Command Set (Continued)
Name
Cmd.
Carrier presence timer
S9=x
Carrier wait timer
S7=x
Country code
N?
Dn
Dial
Dial pause timer
S8=x
Dial tone wait timer
S6=x
Dial wait timer
S7=x
Dialing type
P
Dialing type
T
DTR delay timer
S25=x
Escape code character
S2=x
Escape code guard timer
S12=x
Hang-up delay timer
S38=x
Hookswitch
Hn
Identification and checksum
In
S4=x
Line feed character
Load user configuration profile
Zn
Local DTE echo
En
Long space disconnect
Yn
On
On-line
Private line down timer
S40=x
Private line lookback timer
S41=x
Repeat command
A/
Response mode
Qn
Result code type
Vn
Retransmission counter
S70=x
Ring counter
S1=x
Ringback wait timer
S7=x
RTS-to-CTS delay timer
S26=x
S-Register help
S$
S-Registers
Sn
Speaker operation
Mn
(Sheet 2 of 4)
4-10
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
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Table 4-3
AT Commands Listed by Command Set (Continued)
Name
Cmd.
Speaker volume
Ln
Test mode timer
S18=x
Extended AT& Command Set
AT& command set help
&$
&Bn
Auto Dial Restoral
Automatic fallforward/fallback
&An
CTS operation
&Rn
DCD operation
&Cn
DSR operation
&Sn
DTR On-to-Off transition
&Dn
Front panel lockout
&In
Load fixed configuration profile
&Fn
Maximum DCE speed
&Gn
Network type
&Ln
Operating mode
&Mn
Power-up user configuration profile
&Yn
Private line handshake mode
&Pn
Save settings as a user configuration profile
&Wn
Simulated controlled carrier
&En
Store a phone number
Switched network handshake mode
&Zn=nnn
&Hn
Test mode
&Tn
Transmit clock source
&Xn
Trellis coding
&Un
View stored phone numbers
&V
Extended AT% Command Set
%On
Answer mode
AT% command set help
%$
Auto-reliable fallback character
%An
Call Progress Monitor message response speed
%Rn
Character abort
%Kn
Command format
%Vn
(Sheet 3 of 4)
054R207-000
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V.F 28.8/33.6 Modem DeskTop Platform
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4-11
Table 4-3
AT Commands Listed by Command Set (Continued)
Name
Cmd.
Data compression
%Cn
DSR operation in test mode
%Dn
DTE interface-controlled tests
%En
DTR dialing
%Zn
General security password
%Pn
Inactivity Timer
%Tn
Make busy
%Bn
Private Line Heartbeat
%Hn
Retrain on poor signal quality
%Qn
Extended AT\ Command Set
Asynchronous protocol
AT\ command set help
\Nn
\$
Break character handling
\Kn
Character length
\Bn
Connect message type
\Vn
DTE speed
\Tn
Modem-to-DTE flow control
\Qn
Modem-to-modem flow control
\Gn
Overspeed correction
\An
Parity type
\Pn
Fallback selection and pre-link data buffer
\Cn
Synchronous protocol
\Mn
Extended AT: Command Set
AT: command set help
:$
Private line transmit level
:Tn
Switched network transmit type
:Pn
Extended AT* Command Set
Remote configuration security password
*Pn
Remote configuration write access
*Rn
Remote configuration control
*Wn
Remote configuration exit
*Xn
(Sheet 4 of 4)
4-12
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Table 4-4
Basic AT Command Set Summary
Command
Action
$
$
AT command set help
Display help menu for the basic AT command set
A/
A/
Repeat command
Repeat last command
A
A
Answer call
Answer incoming call
Dn
Dn
Dial
The dial command, followed by one or more dial command
modifiers, manually dials a phone number:
! or &
Flash hookswitch for 1/2 second
, or <
Pause before continuing. Time is in S-Register 8 (default:
2 seconds).
Redial up to n times to achieve data mode
:n
;
Return to AT command mode
@
Wait for quiet answer before continuing. Time is in SRegister 7 (default: 60 seconds).
Ln
Link to cell n if modem can't achieve data mode
Remote modem uses cell n for Security Callback
\n
P
Pulse (rotary) dialing R Reverse to answer mode. Must be
the last character entered.
S
Stored number
T
Tone (DTMF) dialing
W
Wait for dial tone before continuing. Time is in S-Register
6 (default: 2 seconds).
*,#,A,B,C,D,0,1,2,3,4,5,6,7,8,9 (DTMF digits)
0,1,2,3,4,5,6,7,8,9 (pulse digits)
En
E0
E1
Local DTE echo
Disable
Enable
Hn
H0
H1
Hookswitch
Go on-hook (hang up modem)
Go off-hook
In
I0
I1
I2
I3
I4
Identification and checksum
Display product code
Display calculated checksum
Compare stored checksum with calculated checksum
Display firmware revision level (A-)
Display a summary of all S-Registers
(Sheet 1 of 3)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-13
Table 4-4
Basic AT Command Set Summary (Continued)
Command
Action
Ln
L0
L1
L2
L3
Speaker volume
Low volume (per Hayes technical reference manual)
Low volume
Medium volume
High volume
Mn
M0
M1
M2
M3
Speaker operation
Speaker is always Off
Speaker is On while dialing and handshaking, Off in data mode
Speaker is always On
Speaker is Off while dialing, On during handshaking and re-training
N?
N?
Country code
Display modem's current country code configuration
On
O0
O1
On-line
Go on-line (enter data mode)
Go on-line and retrain (at any speed except 300 bps)
P
P
Dialing type
Pulse (rotary) dial
Qn
Q0
Q1
Q2
Response mode
Enable
Disable (enable quiet mode)
Disable in answer mode only
Sn
S$
Sn?
Sn=x
S-Registers
Display help menu for S-Registers
Display contents of S-Register n
Set S-Register n to value x
T
T
Dialing type
Tone (DTMF) dial
Vn
V0
V1
Result code type
Numeric result codes; connect message = VF line speed
Alphanumeric (verbal) result codes; connect and protocol
messages after link; connect message = DTE speed, except for
ITU-T V.14 mode
Xn
X0
X1
X2
X3
X4
Call Progress Monitor (CPM)
Basic results; disable CPM
Extended results; disable CPM
Extended results and detect dial tone only
Extended results and detect busy only
Extended results, full CPM and detect ringback
(Sheet 2 of 3)
4-14
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Table 4-4
Basic AT Command Set Summary (Continued)
Command
Action
Yn
Y0
Y1
Long space disconnect
Disable
Enable
Zn
Zn
Load user configuration profile
Recall (load) user-defined configuration profile n (n = 0 to 3).
Storable S-Registers are stored with user-defined settings.
(Sheet 3 of 3)
Table 4-5
Extended AT& Command Set Summary
Command
Action
&$
&$
AT& command set help
Display help menu for the extended AT& command set
&An
&A0
&A1
Automatic fallforward/fallback
Disable
Enable
&Bn
&B0
&B1
&B2
Auto Dial Restoral
Disable ADR
Enable ADR, with line failure indication
Enable ADR, without line failure indication
&Cn
&C0
&C1
&C2
&C3
Controls the EIA Data Carrier Detect signal.
Selects DCD to be forced On.
Selects DCD to be On after link established.
Selects DCD to be forced On; Toggle Carrier On disconnect.
Selects Real mode (follows modem energy detection.
&Dn
&D0
&D1
&D2
&D3
DTR On-to-Off transition
Ignore (force DTR On)
Enter AT command mode
Go on-hook (hang up)
Same as &D2, but perform the Zn command on a loss of DTR
greater than S-25 timer
&En
&E0
&E1
&E2
Simulated controlled carrier (ITU-T V.13)
Enable in transmit and receive paths
Enable in transmit path only
Enable in receive path only
(Sheet 1 of 4)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-15
Table 4-5
Extended AT& Command Set Summary (Continued)
Command
&Fn
&F0
Action
&F1
&F2
&F3
Load fixed configuration profile
Switched network, asynchronous, ITU-T V.42 error correction, V.42
bis data compression
Switched network, synchronous
Two-wire private (leased) line, asynchronous
Two-wire private (leased) line, synchronous
&Gn
&G5
&G6
&G7
&G8
&G9
&G10
&G11
&G12
&G13
&G14
&G15
&G16
&G17
Maximum DCE speed
4.8 Kbps
7.2 Kbps
9.6 Kbps
12 Kbps
14.4 Kbps
16.8 Kbps
19.2 Kbps
21.6 Kbps
24 Kbps
26.4 Kbps
28.8 Kbps
31.2 Kbps
33.6 Kbps
&Hn
&H0
&H1
&H2
&H3
&H4
&H5
&H6
&H7
&H8
&H9
&H10
Switched network handshake mode
V.34 auto (28.8 kbps to 300 bps)
V.34 only (28.8 kbps to 9600 bps)
ITU-T V.32 bis automatic (14.4 kbps to 300 bps)
ITU-T V.32 bis only (14.4 kbps to 4800 bps)
ITU-T V.32 automatic (9600 bps to 300 bps)
ITU-T V.32 only (9600 bps to 4800 bps)
ITU-T V.22 bis only (2400 bps to 1200 bps)
ITU-T V.22 only (1200 bps)
Bell 212 only (1200 bps)
Bell 103 only (300 bps)
ITU-T V.21 only (300 bps)
&In
&I0
&I1
Front panel control
Disable
Enable
&Ln
&L0
&L1
&L2
Network type
Switched network
Two-wire private (leased) line
Four-wire private (leased) line
(Sheet 2 of 4)
4-16
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Table 4-5
Extended AT& Command Set Summary (Continued)
Command
&Mn
&M0
&M1
Action
&M2
Operating mode
Asynchronous data mode
Asynchronous command mode/synchronous data mode, with DTRto-data delay (S-Register 25)
Synchronous data mode
&Pn
&P0
&P1
&P2
Private (leased) line handshake mode
V.34 only (28.8 kbps to 9600 bps)
ITU-T V.32 bis only (14.4 kbps to 4800 bps)
ITU-T V.32 only (9600 bps to 4800 bps)
&Rn
&R0
CTS operation
Synchronous mode:
Asynchronous mode:
AT command mode:
Synchronous mode:
Asynchronous mode:
AT command mode:
Synchronous mode:
Asynchronous mode:
AT command mode:
Synchronous mode:
Asynchronous mode:
AT command mode:
&R1
&R2
&R3
RTS-CTS delay
On in command mode
Force CTS On
Real
On in command mode
Force CTS On
Real
Real
Real
Force CTS On
Force CTS On
Force CTS On
Note: ITU-T V.13 simulated carrier (&En) and flow control (\Qn)
options override the &Rn settings for CTS in data mode.
&Sn
&S0
&S1
&S2
&S3
DSR operation
Force DSR On; toggle Off on disconnect
Normal DSR operation
DSR follows carrier detect
Force DSR On
&Tn
&T0
&T1
&T3
&T4
&T5
&T6
&T7
Test mode
Cancel (terminate) test mode
Initiate ITU-T V.54 Loop 3 test (ANALOOP)
Initiate ITU-T V.54 Loop 2 test (Digital Loopback)
Enable ITU-T V.54 Loop 2 test (Remote Digital Loopback)
Disable ITU-T V.54 Loop 2 test (Remote Digital Loopback)
Initiate ITU-T V.54 Loop 2 test (Remote Digital Loopback)
Initiate ITU-T V.54 Loop 2 with self-test (Remote Digital Loopback
Self-Test)
Initiate ITU-T V.54 Loop 3 with self-test (ANALOOP Self-Test)
End-to-End Self-Test
&T8
&T9
(Sheet 3 of 4)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-17
Table 4-5
Extended AT& Command Set Summary (Continued)
Command
Action
&Un
&U0
&U1
Trellis coding
Enable
Disable
&V
&V
View stored phone numbers
Display all 10 stored phone numbers, in sequence
&Wn
&Wn
Save settings as a user configuration profile
Save option settings as user configuration profile n in non-volatile
RAM (n = 0 to 3)
&Xn
&X0
&X1
&X2
Transmit clock source
Internal clock (modem)
External clock (DTE)
Receiver wrap clock (network)
&Yn
&Yn
Power-up user configuration profile
Load user configuration profile n at power up (n = 0 to 3)
&Zn=nnn
&Zn=nnn
Store a phone number
Store phone number nnn (including dial command modifiers) in cell
n (n = 0 to 9)
(Sheet 4 of 4)
Table 4-6
Command
Extended AT% Command Set Summary
Action
%$
%$
AT% command set help
Display help menu for the extended AT% command set
%An
%An
Auto-reliable fallback character
Set auto-reliable fallback character to n (n = ASCII 0 to 127)
%Bn
%B0
%B1
%B2
%B3
Make busy
Disable
Enable on loss of DTR
Enable in ITU-T V.54 Loop 3 test (ANALOOP)
Enable in ITU-T V.54 Loop 3 test (ANALOOP), or on loss of RTS or
DTR
Enable on loss of RTS
%B4
(Sheet 1 of 3)
4-18
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Table 4-6
Extended AT% Command Set Summary (Continued)
Command
Action
%Cn
%C0
%C1
%C2
%C3
Data compression
Disable
Enable in transmit and receive paths
Enable in transmit path only in V.42 bis
Enable in receive path only in V.42 bis
%Dn
%D0
%D1
DSR operation in test mode
Force DSR On during ITU-T V.54 Loop 3 test (ANALOOP)
Force DSR Off during this test
%En
%E0
%E1
DTE interface-controlled tests
Disable tests controlled by DTE interface pins
Enable tests (ITU-T V.24 Circuit 140 and 141)
%Hn
Private line heartbeat
%Kn
%K0
%K1
Character abort
2-second delay to character abort
Disable
%On
%O0
%O1
%O2
Answer mode
Answer mode if ringing
Force to answer mode
Automatic answer in originate mode
%Pn
%Pn
%P
General security password
Define general security password (n = 1 to 10 characters)
Disable or clear the password
%Qn
%Q0
%Q1
%Q2
Retrain on poor signal quality
Disable
Attempt up to 3 consecutive retrains; disconnect if not successful
Retrain until signal quality is good
(Sheet 2 of 3)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-19
Table 4-6
Extended AT% Command Set Summary (Continued)
Command
Action
%Rn
%R0
%R1
%R2
%R3
%R4
%R5
%R6
%R7
%R8
%R9
%R10
%R11
%R12
%R13
%R14
%R15
%R16
%R17
%R18
%R19
%R20
%R21
%R22
%R23
%R24
%R25
%R26
%R27
%R28
%R29
Call Progress Monitor (CPM) message response speed
Autobaud
Send at last connect speed
300 bps
1200 bps
2400 bps
4800 bps
7200 bps
9600 bps
12.0 bps
14.4 kbps
16.8 kbps
19.2 kbps
21.6 kbps
24.0 kbps
26.4 kbps
28.8 kbps
31.2 kbps
33.6 kbps
38.4 kbps
57.6 kbps
76.8 kbps
115.2 kbps
128.0 kpbs
32.0 kbps
48.0 kbps
56.0 kbps
64.0 kbps
72.0 kbps
96.0 kbps
112.0 kbps
%Tn
Inactivity timer
%Vn
%V0
%V1
%V2
%V3
%V4
Command format
AT command set
V.25 bis asynchronous command set
V.25 bis HDLC command set
V.25 bis BSC command set
None
%Zn
%Z0
%Z1=x
%Z2
DTR dialing
Ignore
Dial cell x
Go off-hook and attempt to handshake
(Sheet 3 of 3)
4-20
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Table 4-7
Command
Extended AT\ Command Set Summary
Action
\$
\$
AT\ command set help
Display help menu for the extended AT\ command set
\An
\A0
\A1
Overspeed correction
1.25% (nominal) asynchronous overspeed correction
2.5% (extended) overspeed correction
\Bn
\B0
\B1
\B2
\B3
\B4
\B5
Character length (data bits/parity/stop bits)
6N1
7N1
7P1 (\Pn command sets parity type)
8N1
7P2 (\Pn command sets parity type)
8P1 (\Pn command sets parity type)
\Cn
\C0
\C1
\C2
Fallback selection and pre-link data buffer
Timeout and fallback; speed buffer; no data buffer
Timeout and fallback; speed buffer; buffer receive data
Auto-reliable; fallback with fallback character speed buffer; no
receive data buffer
Timeout and fallback; ITU-T V.14; buffer receive data
Timeout or fallback with fallback character; ITU-T V.14; no data
buffer
\C3
\C4
\Gn
\G0
\G1
\G2
\G3
Modem-to-modem flow control
Disable
Enable XON/XOFF in transmit and receive paths
Enable in transmit path only
Enable in transmit and receive paths, with pass-through
\Kn
\K0
\K1
\K2
\K3
\K4
\K5
Break character handling
Expedite break; destroy buffers
Expedite break; save buffers
Timed break; save buffers
Ignore break
Timed break until no break character; save buffers
Timed break until no break character; save buffers
\Mn
\M0
\M1
Synchronous protocol
Normal synchronous mode
ITU-T V.13 synchronous mode (simulated controlled carrier)
\Nn
\N0
\N1
\N4
\N6
Asynchronous protocol
Wire mode
Direct ITU-T V.14 asynchronous mode
V.42 (LAPM) reliable mode (or drop call)
Simulated controlled carrier (ITU-T V.13)
(Sheet 1 of 3)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-21
Table 4-7
Command
Extended AT\ Command Set Summary (Continued)
Action
\Pn
\P0
\P1
\P2
\P3
\P4
Parity type
Even
Space
Odd
Mark
Automatic (from last AT command)
\Qn
\Q0
\Q1
\Q2
\Q3
\Q4
Modem-to-DTE flow control
Disable in both directions
Use XON/XOFF in both directions
Use CTS
Use RTS/CTS
Use XON/XOFF from modem to DTE only
\Tn
\T0
\T1
\T2
\T3
\T4
\T5
\T6
\T7
\T8
\T9
\T10
\T11
\T12
\T13
\T14
\T15
\T16
\T17
\T18
\T19
\T20
\T21
\T22
\T23
\T24
\T25
\T26
\T27
\T28
\T29
DTE speed
Autobaud; %R sets CPM message response speed
Last AT speed
300 bps
1200 bps
2400 bps
4800 bps
7200 bps
9600 bps
12.0 kbps
14.4 kbps
16.8 kbps
19.2 kbps
21.6 kbps
24.0 kbps
26.4 kbps
28.8 kbps
31.2 kbps
33.6 kbps
38.4 kbps
57.6 kbps
76.8 kbps
115.2 kbps
128.0 kbps
32.0 kbps
48.0 kbps
56.0 kbps
64.0 kbps
72.0 kbps
96.0 kbps
112.0 kbps
(Sheet 2 of 3)
4-22
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Table 4-7
Extended AT\ Command Set Summary (Continued)
Command
\Vn
\V0
Action
Connect message type
Connect message reports VF rate upon data mode, link message
after link negotiation (GDC format)
Connect and protocol message sent after link negotiation, connect
reported as DTE rate
Connect and protocol message after link negotiation and Microcom
compatible, connect reported as VF rate
Connect message only after protocol negotiation, connect reported
as DTE rate
Displays the transmit and receive DCE rate as CONNECT rrrrr ttttt,
where rrrrr is receive speed, and ttttt is transmit speed.
(Numeric result codes in asymmetrical mode indicate the receive
speed.)
\V1
\V2
\V3
\V4
(Sheet 3 of 3)
Table 4-8
Extended AT: Command Set Summary
Command
Action
:$
:$
AT: command set help
Display help menu for the extended AT: command set
:Pn
:P0
:P1
Switched network transmit type
Permissive
Programmable
:Tn
:Tn
Private (leased) line transmit level
Set transmit level for private (leased) line to n dBm (n = 0 to 15, for
0 to -15 dBm; range depends on country code configuration)
Table 4-9
Extended AT* Command Set Summary
Command
Action
*$
AT* command set help
*$
Display help menu for the extended AT* command set
*Pn
Remote configuration security password
*Pn
Remote configuration security password (n = 1 to 11 characters)
*P
Disable or clear the password
*Rn
Remote configuration write access
*R0
Enable write access (read/write)
*R1
Disable write access (read only)
*Wn
Remote configuration control
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-23
Table 4-9
Extended AT* Command Set Summary (Continued)
Command
Action
*W0
Disable remote configuration
*W1
Enable remote configuration
*Xn
Remote configuration exit
*X0
Terminate session without saving changes
*X1
Terminate session and save changes
AT Command Reference
All commands are assumed preceded by an AT and followed by a
carriage return. The only exception is the A/ command, which is used
to repeat the last AT command. A description of each command
follows. They are organized alphabetically, with all variations of the
letter grouped together as follows:
•
The basic AT command.
•
The extended AT& command.
•
The extended AT% command.
•
The extended AT\ command.
•
The extended AT: command.
•
The extended AT* command.
Not every letter of the alphabet has a command for each of these
groups.
$
AT command set help
This command causes the modem to display the basic AT command
set help menu.
&$
AT& command set help
This command causes the modem to display the extended AT&
command set help menu.
%$
AT% command set help
This command causes the modem to display the extended AT%
command set help menu.
\$
AT\ command set help
This command causes the modem to display the extended AT\
command set help menu.
:$
AT: command set help
This command causes the modem to display the extended AT:
command set help menu.
*$
4-24
AT* command set help
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
This command causes the modem to display the extended AT*
command set help menu.
S$
S-Register help
This command causes the modem to display the S-Register help
menu. Only S-Registers not containing bit mapped options will be
displayed.
A
Answer call
The A command directs the modem to answer an incoming call. It is
used to go off-hook and generate the proper answer sequence.
&An
Automatic fallforward/fallback
This command controls the automatic fallback and fall forward
capabilities.
&A0
disables the fallforward/fallback feature.
&A1
enables the fallforward/fallback feature.
Note: The &A1 command functions only when the modem is
optioned for synchronous data mode or for asynchronous with speed
buffering, and only for V.32, V.32 bis, and V.34 modes.
%An
Auto-reliable fallback character
This command selects the modem's auto-reliable fallback character,
specified by a number between 0 and 127. The fallback character is
an ASCII character (alphanumeric, punctuation, or control) that the
modem will check for when it performs auto-answer and attempts to
negotiate an auto-reliable (\N3) error correcting link on the VF line. If
the modem detects two successive fallback characters, it will
terminate the negotiation process and go directly to a non-error
correcting mode.
The \C command determines which non-error correcting mode (wire
or direct) the modem will fall back to, and what will become of data
transferred to the modem during the negotiation process.
Appendix E contains a table that lists the ASCII characters and their
corresponding numeric values. Note that fallback character detection
is case-sensitive, since upper and lower case letters are separate
ASCII characters.
\An
Overspeed correction
This option selects overspeed correction for V.14 asynchronous data
modes.
054R207-000
Issue 11
\A0
selects 1.25% (nominal) overspeed correction.
\A1
selects 2.5% (extended) overspeed correction.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-25
A/
Repeat command
The A/ command, the only command not preceded by an AT, is used
to re-execute the most recent AT command line sent to the modem.
This command can be used to cause redial of a previous number
when a handshake attempt fails.
&Bn
Auto Dial Restoral
This command controls Auto Dial Restoral. Refer also to the Auto Dial
Restoral feature description.
%Bn
&B0
disable Auto Dial Restoral.
&B1
enable Auto Dial Restoral, with line failure indicator.
&B2
enable Auto Dial Restoral, without line failure indicator.
Make busy
This command controls the make busy option as follows:
\Bn
%B0
make busy disabled.
%B1
make busy on loss of DTR.
%B2
make busy in ANALOOP.
%B3
make busy on loss of RTS, loss of DTR, or in AL.
%B4
make Busy on loss of RTS.
Character length
This command sets up the character length and format the modem
uses in data mode for front ends that do not send AT commands. The
character length includes start, data, parity, and stop bits. Default is
\B2.
\B0
character length = 8 bits (6 data)
\B1
character length = 9 bits (7 data)
\B2
character length = 10 bits (7 data, 1 parity). With
automatic parity enabled (\P4), this also accommodates 8 data bits with no parity.
\B3
character length = 10 bits (8 data)
\B4
character length = 11 bits (7 data, parity, 2 stop)
\B5
character length = 11 bits (8 data, parity)
Note: The V.42 and MNP protocols (\N2 through \N5) do not
support 11-bit character lengths (\B4 and \B5).
&Cn
DCD operation
The &Cn command controls the EIA Data Carrier Detect signal.
4-26
&C0
selects DCD to be forced On.
&C1
selects DCD to be real (follow modem energy detect).
&C2
selects DCD to be forced On in Command mode, and
real in Data mode.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
%Cn
Data compression
This option controls the selection of data compression for MNP-5
reliable, V.42 bis reliable, and synchronous data links.
\Cn
%C0
disables data compression.
%C1
enables data compression in both directions.
%C2
in V.42 bis or synchronous, enables data compression
in the transmitter path. In MNP 5, enables data
compression in both directions.
%C3
in V.42 bis or synchronous, enables data compression
in the receiver path. In MNP 5, enables data
compression in both directions.
Fallback selection and pre-link data buffer
This command determines fallback selection. If an error correcting
protocol is enabled, this command determines whether incoming data
from the remote modem will be buffered while the receiver modem
waits for establishment of the error correction link.
054R207-000
Issue 11
\C0
receiver modem discards all incoming VF data from the
remote modem until it has sent a PROTOCOL: NONE
message to its DTE. Receiver modem then passes
data through.
\C1
receiver modem buffers incoming VF data (up to 200
characters) until it has sent a PROTOCOL: NONE
message to its DTE. It then passes the buffered data
through to the DTE. The modem will fall back to wire
mode if more than 200 characters are received before
an error correction link is established.
\C2
receiver modem discards all incoming VF data until it
detects two consecutive fallback characters (%An). At
that point it falls back to wire mode. The receiver
modem passes one fallback character through to its
DTE as data.
\C3
same as \C1, except that with no link the modem will
fall back to V.14 (direct) mode.
\C4
same as \C2, except that with no link the modem will
fall back to V.14 (direct) mode.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-27
Dn
Dial
The Dn command is used to initiate a phone number dial. This
command, followed by the number to be dialed, directs the modem to
go off-hook and dial the number (n...). Commands other than dial
modifiers must not be placed after the D command. Any command
that is placed after the D is either ignored or interpreted as a dial
command modifier.
Dial Command Modifiers
T
selects the numbers to be tone dialed.
P
selects the numbers to be pulse dialed (if permitted by
country code).
Sn
selects a stored phone number to be recalled and
dialed. The modem's default when the AT command
DS is issued is to dial the phone number stored in
cell 0. (n = 0 to 9)
R
switches modem operation to handshake in the answer
mode when this command appears as the last
character in the dial string.
, or <
pauses dialing for a programmable length of time
determined by S-Register 8. Default is 2 seconds.
W
directs the dialer to wait for a dial tone before
continuing the dial string.
@
directs the dialer to wait for a quiet answer before
continuing the dial string.
!
directs the dialer to place a 1/2 second hook-switch
flash in the dial string.
;
directs the dialer to return the modem to the command
mode.
:n
directs the dialer to redial the attempted dial string up
to n times if the modem does not achieve data mode.
Ln
directs the dialer to dial phone cell n if the modem fails
to achieve data mode with the current dial string.
\n
remote modem uses cell n for Security Callback.
A
causes the DTMF A tone to be generated.
B
causes the DTMF B tone to be generated.
C
causes the DTMF C tone to be generated.
D
causes the DTMF D tone to be generated.
0-9
tone or pulse dial the appropriate number.
Note:
a.
A, B, C and D are ignored in Pulse mode.
b.
A, B, C and D cannot be dialed from the front panel.
4-28
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
&Dn
DTR On-to-Off transition
The &Dn command controls the result of On-to-Off transitions of Data
Terminal Ready.
%Dn
&D0
causes the modem to ignore Off transitions and forces
internal DTR On.
&D1
causes the modem to change to command mode when
it senses an Off transition during an established data
link.
&D2
causes the modem to recognize Off transitions of DTR
and respond by hanging up.
&D3
functions the same as &D2, and additionally causes
the modem to perform AT command Z.
DSR operation in test mode
This command specifies whether Data Set Ready (DSR) will be On or
Off during an ANALOOP test.
En
%D0
DSR will turn On whenever the modem is operating an
ANALOOP test.
%D1
DSR forced Off when in an ANALOOP test.
Local DTE echo
The En command controls the status of local echo.
&En
E0
turns the local echo Off.
E1
turns the local echo On.
Simulated controlled carrier
The &En command controls the selection of V.13 modes.
%En
&E0
selects Bi-directional V.13.
&E1
selects V.13 TX side enabled.
&E2
selects V.13 RX side enabled.
DTE interface-controlled tests
This option determines whether or not tests can be controlled by DTE
interface leads.
054R207-000
Issue 11
%E0
tests cannot be commanded by signals on the DTE
interface.
%E1
the modem will perform the ANALOOP (AL) test under
command of Pin 18 of the DTE interface, and will
perform the remote digital loop (RDL) test under
command of Pin 21.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-29
&Fn
Load fixed configuration profile
The &Fn command loads the modem with factory-defined settings for
a fixed configuration profile. Table 4-10 lists the settings for the four
fixed configuration profiles.
&F0
selects asynchronous switched network operation, with
V.42 error correction and V.42 bis data compression.
&F1
selects synchronous switched network operation.
&F2
selects asynchronous two-wire private line operation.
&F3
selects synchronous two-wire private line operation.
Table 4-10
Fixed Configuration Profile Settings
Fixed
Profile 0
Fixed
Profile 1
Fixed
Profile 2
Fixed
Profile 3
Answer mode (%O)
Ans. mode
if ringing
Ans. mode
if ringing
Ans. mode
if ringing
Ans. mode
if ringing
Asynchronous protocol (\N)
Autoreliable
Autoreliable
Autoreliable
Autoreliable
Auto Dial Restoral (&B)
Disable
Disable
Disable
Disable
Option (AT Command)
Auto-reliable fallback char. (%A)
"CR”
"CR”
"CR
"CR"
Automatic fallforward/fallback
(&A)
Disable
Disable
Disable
Disable
Break character handling (\K)
See \K5
See \K5
See \K5
See \K5
Call Progress Monitor (X)
Ext.
results/full
CPM
Ext.
results/full
CPM
Ext.
results/full
CPM
Ext.
results/full
CPM
Character abort (%K)
2-sec.
delay
Disable
2-sec.
delay
Disable
Character length (\B)
See \B2
See \B2
See \B2
See \B2
Connect message type (\V)
See \V3
See \V3
See \V3
See \V3
Country code (N)
USA
USA
USA
USA
CPM message response speed
(%R)
Autobaud
speed
Autobaud
speed
Autobaud
speed
Autobaud
speed
CTS operation (&R)
See &R1
See &R2
See &R2
See &R2
Data compression (%C)
Enable
both ways
Enable
both ways
Enable
both ways
Enable
both ways
DCD operation (&C)
Real mode Real mode Real mode Real mode
(Sheet 1 of 4)
4-30
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Table 4-10
Fixed Configuration Profile Settings (Continued)
Fixed
Profile 0
Fixed
Profile 1
Fixed
Profile 2
Fixed
Profile 3
DCE rate limit (&G)
33.6 Kbps
max
33.6 Kbps
max
33.6 Kbps
max
33.6 Kbps
max
Dialing type (P, T)
Tone (T)
Tone (T)
Tone (T)
Tone (T)
DSR operation (&S)
Normal
Normal
Normal
Normal
DSR operation in test mode
(%D)
Forced Off
Forced Off
Forced Off
Forced Off
DTE interface-controlled tests
(%E)
Disable
Disable
Disable
Disable
DTE speed (\T)
Last AT
speed
Auto Baud
Last AT
speed
Auto Baud
DTR dialing (%Z)
Disable
Disable
Disable
Disable
DTR On-to-Off transition (&D)
Ignore
Go onhook
Go onhook
Go onhook
Front Panel Lockout (&I)
Enable
Enable
Enable
Enable
Option (AT Command)
Local DTE echo (E)
Enable
Enable
Disable
Disable
Long space disconnect (Y)
On
On
On
On
Make busy (%B)
Disable
Disable
Disable
Disable
Modem-to-DTE flow control (\Q)
Use CTS
Use CTS
Use CTS
Use CTS
Modem-to-modem flow control
(\G)
Disable
Disable
Disable
Disable
Network type (&L)
Switched
network
Switched
network
Two-wire
Two-wire
private line private line
Operating mode (&M)
Async data Sync data
Async data Sync data
Overspeed correction (\A)
Nominal
Nominal
Nominal
Nominal
Parity type (\P)
Auto
Auto
Auto
Auto
Pre-link data buffer (\C)
See \C2
See \C2
See \C2
See \C2
Private line handshake mode
(&P)
V.34 only
V.34 only
V.34 only
V.34 only
Private line transmit level (:T)
-9 dBm
-9 dBm
-9 dBm
-9 dBm
RDL options (&T4, &T5)
Disable
RDL
Disable
RDL
Disable
RDL
Disable
RDL
Response mode (Q)
Result
codes
Quiet
Quiet
Quiet
Result code type (V)
Verbal
Verbal
Verbal
Verbal
(Sheet 2 of 4)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-31
Table 4-10
Fixed Configuration Profile Settings (Continued)
Fixed
Profile 0
Fixed
Profile 1
Fixed
Profile 2
Fixed
Profile 3
Retrain on poor signal quality
(%Q)
Until SQ is
good
Until SQ is
good
Until SQ is
good
Until SQ is
good
DSR Operation (&S)
Normal
Option (AT Command)
S-Registers (S)
Decimal
(ASCII)
0 Rings to answer on
1
2 Escape code character
43 (+)
3 Carriage return character
13 (CR)
4 Line feed character
10 (LF)
5 Back space character
08 (BS)
6 Wait for dial tone
2 sec.
7 Wait for carrier for W and @ 60 sec.
8 Pause time for , or <
2 sec.
9 Carrier detect response time 0.6 sec.
10Loss of carrier to hang up
1.4 sec.
delay
12Escape sequence guard
1 sec.
time
18Modem test timer
0 sec.
25Delay to DTR - all modes
0.05 sec.
&V0 or %V1 with sync data 5 sec.
modes
26RTS/CTS delay
0 sec.
38Hang-up delay timer
20 sec.
40Private line down timer
1 min
41Private line lookback timer
10 min
42Call failures before modem
N/A
make busy (special feature,
implemented only on a
point-of-sale basis)
70Max. no. of re-transmissions 100
Normal
Normal
Normal
Decimal
(ASCII)
1
43 (+)
13 (CR)
10 (LF)
08 (BS)
2 sec.
60 sec.
2 sec.
0.6 sec.
1.4 sec.
Decimal
(ASCII)
1
43 (+)
13 (CR)
10 (LF)
08 (BS)
2 sec.
60 sec.
2 sec.
0.6 sec.
1.4 sec.
Decimal
(ASCII)
1
43 (+)
13 (CR)
10 (LF)
08 (BS)
2 sec.
60 sec.
2 sec.
0.6 sec.
1.4 sec.
1 sec.
1 sec.
1 sec.
0 sec.
0.05 sec.
5 sec.
0 sec.
0.05 sec.
5 sec.
0 sec.
0.05 sec.
5 sec.
0 sec.
20 sec.
1 min
10 min
N/A
0 sec.
20 sec.
1 min
10 min
N/A
0 sec.
20 sec.
1 min
10 min
N/A
100
100
100
Simulated controlled carrier (&E) Enable
both ways
Enable
both ways
Enable
both ways
Enable
both ways
Speaker operation (M)
Off while
rec. DCD
Off while
rec. DCD
Off while
rec. DCD
Off while
rec. DCD
Speaker volume (L)
Medium
Medium
Medium
Medium
Store password (%P)
None
None
None
None
Switched network handshake
mode (&H)
V.34 auto
V.34 auto
V.34 auto
V.34 auto
Switched network transmit type
(:P)
Permissive Permissive Permissive Permissive
(Sheet 3 of 4)
4-32
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Table 4-10
Fixed Configuration Profile Settings (Continued)
Option (AT Command)
Fixed
Profile 0
Fixed
Profile 1
Fixed
Profile 2
Fixed
Profile 3
Synchronous protocol (\M)
Normal
Normal
Normal
Normal
Transmit clock source (&X)
Internal
Internal
Internal
Internal
Trellis coding (&U)
Enable
Enable
Enable
Enable
Power-up user configuration
profile (&Y)
Fixed
Profile 0
Fixed
Profile 0
Fixed
Profile 0
Fixed
Profile 0
(Sheet 4 of 4)
%Fn=x
Password cell qualifier
This command determines which callback extension(s), if any, can be
used with the password stored in a specified password memory cell.
In the command, n represents the number (0 - 9) of a password
memory cell.
This command does not affect use of the fixed callback extension (,F),
which is administered by an MMS controller.
054R207-000
Issue 11
%Fn=0
disables the use of callback extensions with the
password stored in cell n. The modem will terminate
any call in which it receives that password with a
callback extension attached.
%Fn=1
permits the roving callback extension (,R) to be used
with the password stored in cell n. When the modem
receives the ,R extension attached to the password it
will prompt the remote user for a callback phone
number and then perform the callback procedure. The
password can be used without an extension, but the
use of any extension other than ,R will cause the
modem to terminate the connection.
%Fn=2
permits the phone cell callback extension (,C) to be
used with the password stored in cell n. When the
modem receives the ,C extension attached to the
password it will prompt the remote user for the number
of a phone number memory cell in the answering
modem. The answering modem will then use the phone
number stored in that memory cell to perform the
callback procedure. The password can be used without
an extension, but the use of any extension other than
,C will cause the modem to terminate the connection.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-33
%Fn=3
&Gn
permits the use of either the roving (,R) or phone cell
(,C) callback extension with the password stored in cell
n. When the modem receives an extension attached to
the password it will issue the appropriate prompt to the
remote user and perform the specified callback
procedure. The password can be used without an
extension.
DCE rate limit
This command sets the maximum rate at which the modem can make
a VF connection to a remote modem when using the V.32, V.32 bis,
and V.34 modulation schemes. The allowable rates for each scheme
are:
V.32 only - 4.8 or 9.6 Kbps
V.32 bis only - 4.8 to 14.4 Kbps
V.34 only - 2.4 to 28.8 Kbps
If the rate specified with this command is greater than the highest rate
available with the type of modulation being used, the modem will use
the highest available rate. If the rate specified with this command is
less than the lowest rate available with the type of modulation being
used, the modem will use the lowest available rate.
\Gn
&G5
4.8 Kbps, maximum rate
&G6
7.2 Kbps, maximum rate
&G7
9.6 Kbps, maximum rate
&G8
12 Kbps, maximum rate
&G9
14.4 Kbps, maximum rate
&G10
16.8 Kbps, maximum rate
&G11
19.2 Kbps, maximum rate
&G12
21.6 Kbps, maximum rate
&G13
24 Kbps, maximum rate
&G14
26.4 Kbps, maximum rate
&G15
28.8 Kbps, maximum rate
&G16
31.2 Kbps, maximum rate
&G17
33.6 Kbps, maximum rate (default)
Modem-to-modem flow control
This command is used to provide modem-to-modem flow control for
non-error corrected data links that require a constant speed DTE
interface (Wire Mode).
4-34
\G0
disables flow control between the two modems.
\G1
enables bi-directional modem flow control based on
XON/XOFF signaling. The XON/XOFF signals are
detected, acted on, and deleted from the data stream.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Hn
\G2
provides unidirectional flow control: the modem may
send XON/XOFF signals to the remote modem, yet
ignore and pass through to its DTE any that it receives
as VF signals.
\G3
same as \G1, except that, after they are acted upon,
XON/XOFF signals are passed through to the DTE
instead of being deleted.
Hookswitch
The Hn command controls the off-hook relay.
&Hn
H0
opens the relay for on-hook condition (modem hangup).
H1
closes the relay for off-hook condition. Modem remains
off-hook until termination of on-line status, or until the
H0 command is issued.
Switched network handshake mode
&Hn controls the selection of the switched network hand-shake mode.
Note
a. When the modem is optioned for an external transmit clock
source (&X1), the modem should be optioned for a fixed
handshake mode, not an automatic hand-shake mode (e.g.,
select V.32 bis only [&H3] instead of V.32 bis automatic
[&H2]). The modem will then handshake only at the speed given
to it by the DTE.
b. For 1200 bps V.22 operation, select &H7. &H6 is an auto mode,
so setting the DTE to 1200 bps (\T3) will not force the
connection to 1200 bps.
054R207-000
Issue 11
&H0
selects V.34 auto (28.8 - 300)
&H1
selects V.34 only (28.8 - 9600)
&H2
selects V.32 bis automatic (14.4 - 300)
&H3
selects V.32 bis only (14.4 - 4800)
&H4
selects V.32 automatic (9600 - 300)
&H5
selects V.32 only (9600 - 4800)
&H6
selects V.22 bis only (2400 - 1200)
&H7
selects V.22 only (1200)
&H8
selects 212 only (1200)
&H9
selects 103 only (300)
&H10
selects V.21 only (300)
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-35
%Hn
Private Line Heartbeat (All private Line Products)
EIA TX or RX Data, in half minute intervals, for transmission of the
H<CR> heartbeat on an idle line.
n = 0 to 255
The value disables heartbeat transmission (default).
In
Identification and checksum
The In command requests modem identification and checksum codes
to be transmitted to the DTE.
&In
I0
displays the modem product code. The V.F 28.8/33.6
product code is 288.
I1
displays the stored checksum.
I2
(reserved for future use, displays the OK message)
I3
displays the revision level of the modem's firmware (an
alphabetical character) followed by the OK message.
I4
displays a listing of the following modem information:
Firmware Level - revision level as displayed by I3
Product Type - product code as displayed by I0
Management System - On/Off status of MMS control
Sync Compression - On/Off status
Leased Line - On/Off status; Off = modem configured
for switched network only operation
VF Card - DOM (domestic switched network modem no card), or card's letter identifier (A, B, C, etc.; for
domestic leased line or international modem)
DTE Card - 232, 530, or V35
Country Code - as displayed by the N? command
I5
displays the modem's serial number.
Front panel lockout
This option permits you to disable the modem's front panel switches.
%Kn
&I0
enables front panel.
&I1
disables front panel.
Character abort
This option controls the character abort option. It is only available
when the modem is in AT operation and asynchronous mode.
4-36
%K0
enables character abort: any character typed at the
DTE within 2 seconds after the modem goes off-hook
will abort the dialing process.
%K1
disables character abort.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
\Kn
Break character handling
This command determines how the modem will react to break
characters received from the DTE during an error corrected data link.
Ln
\K0
modem will immediately transmit a break character for
a fixed time (300 ms) and destroy any currently
buffered data.
\K1
same as the \K0 option, except all buffered data will be
saved.
\K2
modem will transmit a fixed time break character in
sequence with the rest of the data (default).
\K3
modem will ignore all breaks received from the DTE.
\K4
modem will transmit break characters in sequence with
the rest of the data as long as the DTE is transmitting
this character.
\K5
same as \K4 - required for compatibility with some
communication software.
Speaker volume
This command controls the volume of the modem's speaker when it is
enabled by the Mn command.
&Ln
L0, L1
both select low volume as per the Hayes Technical
Reference guide.
L2
selects medium volume.
L3
selects high volume.
Network type
This option sets the modem for private line or switched network lines.
Mn
&L0
switched network mode.
&L1
2-wire private line mode.
&L2
4-wire private line mode.
Speaker operation
This command controls when the speaker will be On (audible).
054R207-000
Issue 11
M0
speaker Off at all times.
M1
speaker On during dialing and handshaking, and Off in
data mode.
M2
speaker On at all times.
M3
speaker Off during dialing, and On during handshaking
and retraining.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-37
&Mn
Operating mode
The &Mn command selects between asynchronous and synchronous
operation in data mode. See the %Vn command to select command
mode format.
\Mn
&M0
selects asynchronous operation in data mode. See the
\Nn command to select an asynchronous protocol.
&M1
selects synchronous operation in data mode. See the
\Mn command to select a synchronous protocol.
Synchronous protocol
This command selects the synchronous protocols that are available to
the modem.
N?
\M0
selects normal synchronous mode.
\M1
selects synchronous V.13, simulated controlled carrier,
mode. Select transmit, receive, or bidirectional with
&En command.
\M2
selects synchronous data compression mode. Modem
must be configured for internal transmit timing, and
either Clock Stopping (\Q5) or Clock Throttling (\Q6)
flow control.
Country code
N? will display the current country the modem is configured for. In
general, the country code displayed is the country's international
calling code.
\Nn
Asynchronous protocol
This command is used to select the various possible asynchronous
protocols the modem is allowed to negotiate upon establishing a data
link.
4-38
\N0
options the modem to run in wire mode, performing
speed buffering by copying characters from the VF port
to the DTE port and vice versa.
\N1
options the modem to run in direct mode: the DTE and
VF speeds must match, and there is no speed
buffering. Direct mode is V.14 asynchronous mode.
\N3
options the modem to run in auto reliable mode, and to
negotiate V.42 or alternate links. With no link, the
modem enters wire mode (speed buffering).
\N4
limits error correction to a V.42 (LAPM) link only, or
hang up.
\N6
selects the use of V.13 simulated controlled carrier
operation.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
On
On-line
The On command directs the modem to go on-line (enter data mode)
after an escape to local command mode is issued. This command
transfers the modem from the command to the data mode.
%On
O0
tells the modem to go on-line.
O1
tells the modem to go on-line and issue a retrain
sequence if operating on V.22 bis, V32, V32 bis, or V.34
modes.
Answer mode
For a modem being used on a switched network this option selects
the band the modem will use for answering calls. The selection
applies to both automatically and manually answered calls. For a
modem being used on a private line, this option selects the band the
modem will use for connections.
P
%O0
commands the modem, in switched network mode, to
use the presence of a ring to determine the band,
regardless of whether the talk/data switch (the SEL
key) on the front panel is used or automatic answer is
selected. In private line mode, the modem will be in the
originate band.
%O1
commands the modem to answer calls in the answer
band in either switched network or private line mode.
%O2
commands the modem to answer calls in the originate
band in either switched network or private line mode.
Dialing type
This command directs the modem to use pulse dialing as its selected
dialing method. The command may be used alone or as part of a dial
string.
When P is used alone as a command it makes pulse dialing the
modem's default - to be used unless a dial string includes a tone
modifier. When P is used in a dial string, it acts as a modifier and
affects only the dialing of that string.
Pulse dialing is blocked by some country code configurations.
&Pn
Private line handshake mode
&Pn controls the selection of the private line handshake mode.
054R207-000
Issue 11
&P0
selects V.34 only (28.8 - 9600)
&P1
selects V.32 bis only (14.4 - 4800)
&P2
selects V.32 only (9600 and 4800)
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
4-39
%Pn=nnn
Store password
This command stores a password in one of the 10 memory cells (n =
0 - 9) the modem provides for that purpose. Each password (nnn) can
consist of up to 10 characters.
Refer also to the Passwords feature description.
nnn = password, 1 to 10 characters (to disable or clear the password,
enter %P).
\Pn
Parity type
This command sets up what parity to use in data mode for front ends
that do not send AT commands.
:Pn
\P0
even parity
\P1
space parity
\P2
odd parity
\P3
mark parity
\P4
automatic parity; last AT (default)
Switched network transmit type
This command allows you to select permissive or programmable
mode for switched network operation.
*Pn
:P0
selects permissive mode.
:P1
selects programmable mode.
Remote configuration security password
This command defines the remote configuration security password.
Refer also to the Remote Configuration feature description.
n = password, 1 to 11 characters (to disable or clear the password,
enter *P).
Qn
Response mode
The Qn command controls the transmission of result codes.
%Qn
Q0
requests non-quiet mode: result codes are transmitted
to the DTE as appropriate.
Q1
requests quiet mode: modem does not send any result
codes to the DTE.
Q2
disables Call Progress Monitor responses in answer
mode only. Modem enters this mode on detection of
ring signal.
Retrain on poor signal quality
This option controls retrain initiation.
4-40
%Q0
disables retrain initiation.
%Q1
modem will try up to 3 consecutive retrains upon
detection of poor signal quality. If not successful, the
modem will disconnect the line.
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%Q2
\Qn
modem will retrain on poor signal quality until signal
quality is OK.
Modem-to-DTE flow control
This command selects the type of data mode flow control used on the
DTE port.
&Rn
\Q0
disables all flow control.
\Q1
enables XON/XOFF signaling between modem and
DTE.
\Q2
enables the modem to flow control the DTE via CTS.
\Q3
operates the same as the \Q2 option, and also allows
the DTE to flow control the modem via RTS as a ready
to receive signal.
\Q4
allows the modem to XON/XOFF the DTE yet ignore
these signals when sent by the DTE (unidirectional flow
control).
\Q5
allows the modem to flow control the DTE by almost
stopping the transmit clock (internal transmit timing
must be selected). Used with synchronous data
compression.
\Q6
allows the modem to flow control the DTE by varying
the rate of the transmit clock (internal transmit timing
must be selected). Used with synchronous data
compression.
CTS operation
The &Rn command defines the functionality of the Request to Send
and Clear to Send EIA interchange circuits.
&R0
causes CTS to follow RTS with an interjected delay
specified in S-Register 26 when in synchronous mode.
In asynchronous command mode, CTS will be On.
Upon reaching asynchronous data mode, CTS will
follow the applicable ITU-T specification for the
modulation chosen during handshake.
&R1
causes CTS to follow the applicable ITU-T specification
in data mode (in synchronous modes, CTS will not
follow RTS) and in command mode CTS will be On.
&R2
causes CTS to follow the applicable ITU-T specification. During test modes, CTS will follow V.54
conventions. CTS does not follow RTS in data modes.
CTS will go Off after the call is dropped.
&R3
forces CTS On in all modes of operation (RTS is
ignored).
Note: V.13 and flow control options override &R settings for CTS.
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%Rn
Call Progress Monitor message response speed
%Rn options control the rate at which Call Progress Monitor (CPM)
responses are sent to the DTE when the modem is optioned for \T0.
%R0
\Rn
Auto speed
%R1
last AT speed
%R2
300 bps
%R3
1200 bps
%R4
2400 bps
%R5
4800 bps
%R6
7200 bps
%R7
9600 bps
%R8
12.0 kbps
%R9
14.4 kbps
%R10
16.8 kbps
%R11
19.2 kbps
%R12
21.6 kbps
%R13
24.0 kbps
%R14
26.4 kbps
%R15
28.8 kbps
%R16
31.2 kbps
%R17
33.6 kbps
%R18
38.4 kbps
%R19
57.6 kbps
%R20
76.8 kbps
%R21
115.2 kbps
%R22
128.0 kbps
%R23
32.0 kbps
%R24
48.0 kbps
%R25
56.0 kbps
%R26
64.0 kbps
%R27
72.0 kbps
%R28
96.0 kbps
%R29
112.0 kbps
Enable and Disable asymmetrical rates
\R0
disable asymmetrical rates - when this command is
active the transmit and receive DCE rate will be the
same.
\R1
enable asymmetrical rates - when this command is
active (BUFFERED ASYNCHRONOUS MODES
ONLY) the transmit and receive DCE rates may be
negotiated for different rates based on the line
conditions. The modems receiver will select the remote
modems transmit rate.
Special Considerations:
1. The following commands disable asymmetrical rates: \N1, \N6
and &M1.
2. The &Gn command limits only the rate of the receiver in \R1
mode.
3. The \V0 and \V2 command formats remain the same reporting
the receivers rate.
4. The \V4 command reports the asymmetrical rates.
5. Front panels report the Receive Rate.
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*Rn
Remote configuration write access
This command controls remote configuration write access. Refer also
to the Remote Configuration feature description.
Sn
*R0
enables write access (read/write).
*R1
disables write access (read only).
S-Registers
The S command allows you to view (Sn?) or change (Sn=x) the SRegisters. The S-Registers store values for functions that are not
often changed, such as timers or counters, and the ASCII values of
control characters, such as Carriage Return. Table 4-11 summarizes
the S-Register set. It is followed by a detailed command reference.
Examples:
To view the value of S-Register 2, type:
ATS2?<cr>
The response might be:
005<cr><lf>
OK<cr><lf>
To set the value of S-Register 2 to equal 5, type:
ATS2=5<cr>
To view the value of the last S-Register that was queried, type:
AT?<cr>
S$
S-Register help
This command causes the modem to display the S-Register Help
Menu.
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Table 4-11
S-Reg.
S-Register Summary
Function
Decimal ASCII
Units
Storable
0
Automatic answer
0
Yes
1
Ring counter
0
2
Escape code character
43
3
Carriage return character
13
CR
No
4
Line feed character
10
LF
No
BS
No
+
No
5
Backspace character
08
6
Dial tone wait timer
02
seconds
Yes
No
7
Carrier wait timer; W and @
dial command modifier wait
timer; ringback wait timer
60
seconds
Yes
8
Dial pause timer for , and <
dial command modifiers
02
seconds
Yes
9
Carrier presence timer
06
0.1 second
Yes
10
Carrier loss timer
14
0.1 second
Yes
12
Escape code guard timer
50
0.02 second
No
18
Test mode timer
00
10 seconds
Yes
25
DTR delay timer
0.05
seconds
(&M0)
Yes
005
seconds
(&M1)
26
RTS-to-CTS delay timer
00
milliseconds
38
Hang-up delay timer
20
seconds
Yes
40
Private line down timer
01
minutes
Yes
41
Private line lookback timer
01
10 minutes
Yes
70
Retransmission counter
100
100
Adjustable transmitter level
display
4-44
Yes
Yes
dBm
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S-Register 0
Automatic answer
This register determines the number of rings the modem must
detect before answering a telephone call. It is programmable
from 0 to 255. If the register value is 0, automatic answer is
disabled. There is a default value of 2 rings if automatic answer is
turned On.
S-Register 1
Ring counter
This register counts incoming rings detected. It increments upon
each detected ring, and is cleared after 8 seconds of ring silence
and Idle mode. It cannot be cleared in data mode.
S-Register 2
Escape code character
This register holds the ASCII equivalent of the Escape Code
character. Its range is from 0 to 127, and the default is 43 (+).
Any value above 127 effectively disables the Escape code
function.
S-Register 3
Carriage return character
This register holds the ASCII equivalent of the Carriage Return
character. Its range is from 0 to 127, and the default is 13 (<cr>).
S-Register 4
Line feed character
This register holds the ASCII equivalent of the Line Feed
character. Its range is from 0 to 127, and the default is 10 (<lf>).
S-Register 5
Backspace character
This register holds the ASCII equivalent of the Backspace
character. Its range is from 0 to 127, and the default is 08 (H).
S-Register 6
Dial tone wait timer
This register is the programmable dial tone wait timer that
determines how many seconds the modem will wait for a dial
tone before it starts dialing. This register applies only when blind
dialing is selected (X0, X1, or X3). This register can be set from 0
to 255. The default is 2 seconds.
S-Register 7
Carrier, dial and ringback wait timer
This register stores the carrier wait time, how many seconds the
modem will wait for carrier detection after dialing has been
completed.
The wait time set in this register is also used for the dial
command modifiers W (wait for dial tone before dialing) and @
(wait for quiet answer before dialing).
This register also sets the number of seconds the modem will
wait for ringback when originating a call. This condition only
occurs when using extended result code options X3 or X4.
This register can be programmed for from 1 to 60 seconds. The
default is 60 seconds.
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S-Register 8
Dial pause timer
This register stores the duration, in seconds, of the pause that
will occur when either of the pause dialing modifiers (, or <) is
used. It can be programmed from 0 to 255. The default is 2
seconds.
S-Register 9
Carrier presence timer
The value in this register determines how many tenths of a
second the carrier signal must be present following a carrier loss
before the modem will turn on the EIA DCD signal to the DTE.
This is called loss of carrier reacquire debounce time. The
register's range is from 1 to 255. The default is 6 (0.6 second).
S-Register 10
Carrier loss timer
The value in this register determines how many tenths of a
second the remote carrier signal must be lost before the local
modem disconnects. The delay permits the carrier to disappear
momentarily without causing the modem to hang up. The
register's timer range is from 1 to 254. Selecting 255 disables
disconnect.
The modem recognizes a carrier after a period of time specified
in S9. Therefore, if the value of S10 is less than that set for S9,
even a momentary loss of carrier will cause the modem to
disconnect.
When the modem is operating in half-duplex asynchronous
mode, it ignores the value of this register.
S-Register 12
Escape code guard timer
The value in this register determines (in 50ths of a second) the
Escape code guard time the modem will use to recognize a valid
escape sequence. The modem constantly monitors the data
stream for the occurrence of three consecutive +++ (escape code
characters) within the time specified in this register. The modem
will transfer from the data mode to the command mode when it
detects such an occurrence. This register may be set from 1 to
255. The default is 50 (1 second).
S-Register 18
Test mode timer
The value in this register determines (in 10-second increments)
how long automatically timed tests will run. It may be set from 0
(no time out, tests run until ended manually) to 60 (10 minutes).
The default is 0.
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S-Register 25
DTR delay timer
This register sets the delay for DTR, but its precise function
depends on the modem's Operating Mode (&Mn command) and
Command Format (%Vn command).
When the modem is configured for asynchronous Operating
Mode (&M0), the value in this register is always the time used to
debounce the DTR signal. It is set in hundredths of a second (0
to 255). The default is 5 (0.05 second).
When the modem is configured for synchronous Operating Mode
(&M1) and an asynchronous Command Format (%V0 or %V1),
this register initially sets the time available to the operator for
switching the EIA cable from asynchronous equipment to
synchronous equipment. It can be set from 0 to 255 seconds.
The default is 5 seconds. After the whole-second timer expires,
the register is then used to debounce the DTR signal, as above.
The same number, stored in the register, is applied to both the
whole-second and hundredth-of-a-second counts.
S-Register 26
RTS-to-CTS delay timer
The value in this register determines (in milliseconds) the amount
of delay between RTS and CTS. It can be set from 0 to 255. The
default value is 0.
S-Register 38
Hang-up delay timer
The value in this register determines the maximum delay (in
seconds) between the modem's receipt of the command to hang
up and the disconnect operation. (If the modem is configured to
follow the DTR signal, an On-to-Off transition acts as a command
to hang up.) This register is useful for error-control and speedbuffering communications to ensure that data in the modem
buffers is sent before the connection is terminated.
If this register is set between 0 and 254, the modem will wait up
to that number of seconds for the remote modem to acknowledge
receipt of all data buffers before hanging up. The default is 20. If
all data is transmitted prior to the timeout, the response to the H0
command will be OK. If the timeout occurs before all data can be
sent, the NO CARRIER (3) result code will be sent to indicate
that data has been lost.
If this register is set to 255, the modem does not time-out, and
continues to attempt to deliver data in the buffers until the
connection is lost, or the data is delivered.
S-Register 40
Private line down timer
The value in this register determines (in minutes) how long the
modem will continue private line retrains before it attempts a
switched network connection. It can be set from 0 (timer
disabled) to 255.
Refer also to the Auto Dial Restoral feature description.
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S-Register 41
Private line lookback timer
The value in this register determines (in 10 minute increments)
how long the modem will operate in switched network mode
before it automatically attempts to return to private line mode. It
can be set from 0 (timer disabled) to 255. When the timer is
disabled, the modem does not automatically attempt to return to
the private line.
Refer also to the Auto Dial Restoral feature description.
S-Register 42
Call failures before modem make busy
This feature is only enabled in the modem by special
arrangement between the customer and GDC. When it is
enabled the modem will take itself out of service by presenting a
busy signal on the telephone line when the number of
consecutive failed calls equals the number configured here. It
can be set from 3 to 15.
S-Register 70
Retransmission counter
The value in this register determines how many times the modem
will retransmit any one frame while in an error correcting
connection. The modem hangs up when it reaches the limit set
by this register. It can be set from 0 to 255. The default is 100.
Retransmissions become necessary when data errors
introduced by noise disrupt the reception of a frame. Raising this
limit may be necessary if, for example, telephone lines are
extremely noisy. The retransmission delays may be undesirable,
but the modem will not hang up.
S-Register 100 Adjustable transmit level display
When you issue the command S100? the value in this register
displays the transmit level configured in the modem. This register
is not a valid display in any country, such as the United States,
that limits transmit level selections to Programmable or
Permissive.
&Sn
DSR operation
This command controls how the Data Set Ready EIA interchange
circuit will operate.
&S0
selects DSR to remain On and glitch Off for
disconnect.
&S1
causes DSR to be real (per ITU-T).
&S2
selects DSR to follow carrier detect.
&S3
selects DSR forced On in all modes.
Note: The %Dn command overrides the functionality of this
command during any ANALOOP test.
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%Sn
Password operation
This command selects what type of password security the
modem will enforce.
T
%S0
password security disabled.
%S1
general security password enforcement enabled.
This is the GDC proprietary handshake password.
Originating modem transmits contents of password
cell 0. Answering modem compares received
password to contents of password cell 0.
%S2
on-line password enforcement enabled. Answering
modem prompts remote for manually input
password; checks for match in any password cell,
0 - 9.
%S3
both handshake and on-line password enforcement
enabled.
%S4
enable mandatory Callback Security - when this
command is active pass-through security is
disabled.
%S6
Enables Online Security with manadatory call-back.
%S7
Enables SteadFast Security and Online Security
with mandatory call-back.
Dialing type
This command directs the modem to use tone dialing as its
selected dialing method. The command may be used alone or as
part of a dial string.
When T is used alone as a command it makes tone dialing the
modem's default - to be used unless a dial string includes a pulse
modifier. When T is used in a dial string, it acts as a modifier and
affects only the dialing of that string.
&Tn
Test mode
The &Tn command controls the soft operation of test modes.
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&T0
clears any active test and resumes normal data set
operation.
&T1
initiates a soft ANALOOP test mode that directs all
local data through the transmitter and receiver of
the modem. To terminate this test, type +++
(escape sequence) followed by &T0.
&T3
initiates a soft Digital Loop test mode that directs all
received data from the remote modem to be looped
back to the transmit data. This has the effect of
echo on the remote DTE. Any data the remote DTE
sends is returned.
&T4
directs the modem to accept the in-band request to
initiate a remote digital loopback.
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&T5
directs the modem to ignore the in-band request to
initiate a remote digital loopback.
&T6
directs the modem to transmit the in-band request
to establish a remote digital loopback with the far
modem.
&T7
directs the modem to transmit the in-band request
to establish a remote digital loopback with the far
modem, and to run the self-test pattern generator.
&T8
directs the modem to enter the ANALOOP test
mode, and to run the self-test pattern generator.
&T9
directs the modem to send a self-test pattern to the
remote modem while checking the receive data for
the same test pattern and checking for errors.
All tests operate for the amount of time specified in
S-Register 18. Pending tests such as DL are not allowed.
The self-test pattern for speeds of 1200 and 2400 bps is made up
of alternate ones and zeros; the 511 pattern is generated for all
other speeds.
Remote digital loopback and self-tests are not operational when
the modems are passing data at 300 bps.
%Tn
Inactivity Timer (Switched Network)
Sets the inactivity Time-out Timer on idle TX or TX Data, in
minute intervals, for disconnecting the line when this idle period
is reached.
n = 0 to 255
The 0 value disables the Inactivity Timer (default).
\Tn
DTE speed
This command, in conjunction with the switched network
handshake mode command (&Hn), controls the DTE speed.
There are several configurations to consider:
a. An automatic handshake mode (e.g., V.32 bis auto [&H1],
V.32 auto [&H4], V.22 bis only [&H6]) takes precedence over
the \Tn selection, and the modem tries for the highest VF
speed common to the two commands.
b. For 1200 bps V.22 operation, select &H7. &H6 is an auto
mode, so setting the DTE to 1200 bps (\T3) will not force the
connection to 1200 bps.
c. When the modem is optioned for an automatic hand-shake
mode and direct V.14 asynchronous mode (\N1), it sends a
connect message to the DTE at the selected \Tn speed. In
order to pass data, the user must change the DTE's speed to
match the displayed connect speed.
d. When the modem is optioned for speed buffering (\N0), the
\Tn command alone selects the DTE speed, and the &Hn
command selects the hand-shake mode.
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e.
f.
:Tn
When the modem is optioned for a fixed handshake mode
and direct mode (\N1), the \Tn command selects not only the
DTE speed, but also forces the VF speed to match it. If this
speed is not available, the modem drops the call. (This does
not apply to V.22 bis only, which handshakes at the highest
VF speed.)
When using the modem in direct mode (\N1), if the desired
connect speed is known, set the speed to match using the
\Tn command. Set the DTE to the same speed and "AT" the
modem so that it will know at what speed to send messages.
\T0
Auto Baud speed
\T1
\T2
300 bps
\T3
1200 bps
\T4
2400 bps
\T5
4800 bps
\T6
7200 bps
\T7
9600 bps
\T8
12.0 kbps
\T9
14.4 kbps
last AT speed
\T10
16.8 kbps
\T11
19.2 kbps
\T12
21.6 kbps
\T13
24.0 kbps
\T14
26.4 kbps
\T15
28.8 kbps
\T16
31.2 kbps
\T17
33.6 kbps
\T18
38.4 kbps
\T19
57.6 kbps
\T20
76.8 kbps
\T21
115.2 kbps
\T22
128.0 kbps
\T23
32.0 kbps
\T24
48.0 kbps
\T25
56.0 kbps
\T26
64.0 kbps
\T27
72.0 kbps
\T28
96.0 kbps
\T29
112.0 kbps
Private line transmit
This command enables you to select the transmit level for private
line data links. The range may be limited on a per country code
basis. The range is n = 0 to -15 dBm. The default value is -9
dBm.
&Un
Trellis coding
When the modem is operating in V.32 mode at 9600 bps this
option allows you to select Trellis coded data (&U0), or uncoded
data (&U1).
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&U0
enables Trellis coding.
&U1
disables Trellis coding.
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Vn
Result code type
This command controls the transmission of result codes. Refer to
the \Vn command for a list of all possible result codes.
&V
V0
selects the non-verbal (numeric equivalent) result
codes to be transmitted. The connect message is
the VF line speed.
V1
selects verbal result codes. The connect message
is the DTE speed, except for V.14 mode.
View stored phone numbers
This option displays the 10 stored telephone number cells. When
this command is selected from the LCD it will display one cell at a
time, and can be scrolled from cell 0 to 9.
%Vn
Command format
This command determines the command format.
Note: When either of the two asynchronous command formats
(%V0 or %V1) is used with synchronous data mode (&M1) a
special function of S-register 25 comes into effect. Consult the
description of S-register 25 for further information.
%V0
\Vn
AT command set
%V1
V.25 bis asynchronous command set
%V2
V.25 bis HDLC (High-level Data Link Control)
command set
%V3
V.25 bis BSC (IBM Binary Synchronous
Communications) command set
%V4
None
Connect message type
This command determines the type of connect message sent to
the DTE upon establishing a data link.
\V0
4-52
options the modem to send the standard GDC
Connect message upon reaching data mode plus
V.42 messages after the link negotiation. The
connect message displays the VF line speed.
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MEANING
VERBAL RESPONSE
NUMERIC
COMMAND WAS SUCCESSFUL
OK
0
COMMAND FAILED
ERROR
4
LINK ESTABLISHED
CONNECT
1
INCOMING RING DETECTED
RING
2
RINGBACK DETECTED
RINGING
23
EXCHANGE CANNOT DIAL NUMBER
UNOBTAINABLE NUMBER
24
LINK DROPPED
NO CARRIER
3
DIAL TONE NOT PRESENT
NO DIALTONE
6
REMOTE NOT ANSWERING
NO ANSWER
8
LINE BUSY
BUSY
7
LINK ESTABLISH AT 300
CONNECT
1
LINK ESTABLISH AT 1200
CONNECT 1200
5
LINK ESTABLISH AT 2400
CONNECT 2400
10
LINK ESTABLISH AT 4800
CONNECT 4800
11
LINK ESTABLISH AT 7200
CONNECT 7200
15
LINK ESTABLISH AT 9600
CONNECT 9600
12
LINK ESTABLISH AT 12000
CONNECT 12000
16
LINK ESTABLISH AT 14400
CONNECT 14400
17
LINK ESTABLISH AT 16800
CONNECT 16800
18
LINK ESTABLISH AT 19200
CONNECT 19200
14
LINK ESTABLISH AT 21600
CONNECT 21600
19
LINK ESTABLISH AT 24000
CONNECT 24000
20
LINK ESTABLISH AT 26400
CONNECT 26400
21
LINK ESTABLISH AT 28800
CONNECT 28800
22
LINK ESTABLISH AT 31200
CONNECT 31200
23
LINK ESTABLISH AT 33600
CONNECT 33600
24
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With \V0 and \V1, the following connect messages are sent when
link negotiation is complete:
MEANING
VERBAL RESPONSE
NUMERIC
NO PROTOCOL
PROTOCOL:NONE
70
V.42 PROTOCOL
PROTOCOL:V.42
77
V.42 BIS PROTOCOL
PROTOCOL:V.42BIS
79
\V1
MEANING
options the modem to delay sending the Connect
message until an error corrected link has been
established. The Connect message indicates DTE
speed unless a V.14 connection was established, in
which case it will indicate the VF speed.
VERBAL RESPONSE
NUMERIC
DTE LINK AT 300
CONNECT
1
DTE LINK AT 1200
CONNECT 1200
5
DTE LINK AT 2400
CONNECT 2400
10
DTE LINK AT 4800
CONNECT 4800
11
DTE LINK AT 7200
CONNECT 7200
15
DTE LINK AT 9600
CONNECT 9600
12
DTE LINK AT 12000
CONNECT 12000
16
DTE LINK AT 14400
CONNECT 14400
17
DTE LINK AT 16800
CONNECT 16800
18
DTE LINK AT 19200
CONNECT 19200
14
DTE LINK AT 21600
CONNECT 21600
19
DTE LINK AT 24000
CONNECT 24000
20
DTE LINK AT 26400
CONNECT 26400
21
DTE LINK AT 28800
CONNECT 28800
22
DTE LINK AT 38400
CONNECT 38400
25
DTE LINK AT 57600
CONNECT 57600
26
DTE LINK AT 76800
CONNECT 76800
27
DTE LINK AT 115200
CONNECT 115200
28
DTE LINK AT 128000
CONNECT 128000
29
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\V2
MEANING
is similar to the \V1 function except that /REL will be
included at the end of the message when a V.42
error corrected link has been established.
Message Numbers 0 - 10 are the same as for \V0.
VERBAL RESPONSE
NUMERIC
RELIABLE DTE LINK AT 300
CONNECT REL
30
RELIABLE DTE LINK AT 1200
CONNECT 1200/REL
31
RELIABLE DTE LINK AT 2400
CONNECT 2400/REL
32
RELIABLE DTE LINK AT 4800
CONNECT 4800/REL
33
RELIABLE DTE LINK AT 7200
CONNECT 7200/REL
34
RELIABLE DTE LINK AT 9600
CONNECT 9600/REL
35
RELIABLE DTE LINK AT 12000
CONNECT 12000/REL
36
RELIABLE DTE LINK AT 14400
CONNECT 14400/REL
37
RELIABLE DTE LINK AT 16800
CONNECT 16800/REL
38
RELIABLE DTE LINK AT 19200
CONNECT 19200/REL
39
RELIABLE DTE LINK AT 21600
CONNECT 21600/REL
40
RELIABLE DTE LINK AT 24000
CONNECT 24000/REL
41
RELIABLE DTE LINK AT 26400
CONNECT 26400/REL
42
RELIABLE DTE LINK AT 28800
CONNECT 28800/REL
43
RELIABLE DTE LINK AT 31200
CONNECT 31200/REL
44
RELIABLE DTE LINK AT 33600
CONNECT 33600/REL
45
RELIABLE DTE LINK AT 38400
CONNECT 38400/REL
46
RELIABLE DTE LINK AT 57600
CONNECT 57600/REL
47
RELIABLE DTE LINK AT 76800
CONNECT 76800/REL
48
RELIABLE DTE LINK AT 115200
CONNECT 115200/REL
49
RELIABLE DTE LINK AT 128000
CONNECT 128000/REL
50
\V3
Note
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sends only the connect message after the link
negotiation. The message will indicate the VF rate
for V.13 and V.14 connections, and the DTE rate for
all other connections (default).
Verbal text responses are terminated by <cr><lf>.
Numeric code responses are terminated by <cr>.
V.F 28.8/33.6 Modem DeskTop Platform
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&Wn
Save settings as a user configuration profile
This command directs the modem to write the current settings for
user defined and storable options into memory. You can save up
to four user configuration profiles
(n = 0 - 3)
Zn is the command for loading a user configuration profile that
has been stored by means of this command.
*Wn
Remote configuration control
This command controls remote configuration. Refer also to the
Remote Configuration feature description.
Xn
*W0
disables remote configuration.
*W1
enables remote configuration.
Call Progress Monitor
This command controls which Call Progress Monitor (CPM)
signals are monitored and reported to the local DTE. This option
is user storable unless it is defined by country configuration
parameters.
&Xn
X0
forces the modem to blind dial, and will only send a
CONNECT message for all established links. All
CPM is disabled.
X1
blind dial, CPM disabled, CONNECT message
includes connected speed.
X2
CPM enabled for pre-dial signals (dialtone) only,
CONNECT message includes connected speed.
X3
blind dial, CPM enabled for post-dial signals (busy,
unobtainable number, etc.) only, CONNECT
message includes connected speed.
X4
enables CPM response codes and monitoring,
CONNECT message includes connected speed.
X5
enables all CPM response codes and monitoring,
including ringback detection, CONNECT message
includes connected speed.
Transmit clock source
This command selects the clock source when the modem
operates in synchronous Data Mode.
4-56
&X0
directs the modem to use the internally generated
clock source.
&X1
selects the DTE clock as a source for the modem.
&X2
selects the modem's RECEIVER derived timing
clock to be used in the transmitter.
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*Xn
Remote configuration exit
This command controls remote configuration exit. Refer also to
the Remote Configuration feature description.
Yn
*X0
terminates the session without saving changes.
*X1
terminates the session and saves changes.
Long space disconnect
This command enables or disables the long space disconnect
option. When the option is enabled a disconnect request (ATH0,
loss of DTR or DCD, etc.) will cause the modem to transmit 4
seconds of continuous space (BREAK). A modem with long
space disconnect enabled will hang up when it receives more
than 1.5 seconds of continuous space (BREAK) while on-line.
&Yn
Y0
disables long space disconnect.
Y1
enables long space disconnect.
Power-up user configuration profile
This command is used to determine which user configuration
profile, stored by means of the &Wn command, is activated at
modem power-up. You can select from up to four user
configuration profiles (n = 0 - 3).
Zn
Load user configuration profile
This command re-initializes the modem options with a userdefined configuration profile that has been stored by means of
the &Wn command. You can select from up to four user
configuration profiles (n = 0 - 3).
&Zn=nnn
Store a phone number
This command stores a telephone number (nnn) in a memory
cell (n). The equal sign can be followed by up to thirty-six
characters, including any of the commands that can be used in a
dial string. There are 10 cells (n = 0 to 9) available in which to
store telephone numbers.
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%Zn
DTR dialing
This command controls the Off-to-On DTR transition options for
DTR dialing.
Note
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%Z0
sets the modem to ignore the Off-to-On transition of
DTR.
%Z1
sets the modem to dial when a DTR Off-to-On
transition occurs and DTR remains On. The format
for this command is %Z1=x, where x is the memory
cell that contains the number to be dialed. The
specified phone cell must be programmed with a
valid phone number prior to this operation. When
no cell number is provided, Cell 0 is the default.
%Z2
sets the modem to go off-hook and try to
handshake on an Off-to-On transition of DTR.
%Z3
performs the same function as %Z1 with one
additional feature: modem will redial if the
connection is broken while DTR remains On. %Z1
dials only on transition. The format for this
command is %Z3=x.
The &D0 command overrides this option.
V.F 28.8/33.6 Modem DeskTop Platform
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Chapter 5: V.25 bis Command Set
Operation
Overview
This section describes the operating procedures for the V.F 28.8/33.6
modem when using the ITU-T (formerly CCITT) V.25 bis compatible
command protocol (command set).
108 Modes
The ITU-T V.25 bis protocol operates in one of two modes: 108.2 or
108.1. The modes are named for the two ITU-T designations for circuit
108 of the terminal interface:
•
In 108.2 mode, the circuit is the "Data Terminal Ready" signal.
•
In 108.1 mode, the circuit is the "Connect Data Set to Line" signal.
Circuit 108 is pin 20 in a DB25 connector; in a 34-pin V.35 connector
it is pin H.
108.2 Mode
The 108.2 operating mode supports convenient outbound calling to
multiple locations. When the DTE instructs the modem to originate a
call in 108.2 mode, it also specifies the number to be dialed. The DTE
can either supply the number itself along with the command to dial, or
identify which of the modem's memory cells contains the number to be
dialed.
In 108.2 mode the modem supports an ITU-T V.25 bis compatible
command set you can use from the DTE to interrogate and configure
the modem, and to control communication and test functions.
Configuration by means of the command set can include operating
parameters such as data rate, handshake mode, and synchronous timing
source; as well as storage of phone numbers in the modem's memory
cells.
In order for the V.25 bis command set to function, the modem must be
operating in 108.2 mode and terminal interface circuit 108.2 (Data
Terminal Ready) must be On. When circuit 108.2 is Off, the modem
ignores the commands. Circuit 108.2 can be forced On with the &D0
AT command (this can only be done in asynchronous operations).
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108.1 Mode
The 108.1 operating mode supports automatic outbound calling
directed primarily to a single location. The DTE instructs the modem
to originate a call by turning On circuit 108.1, Connect Data Set to
Line. The modem then goes off-hook, dials the number stored in its
memory cell 0, and attempts to establish communication.
The modem will disconnect from the line if it does not successfully
handshake in the time specified in the abort timer selected by the S7=x
AT command (default is 30 seconds). If you turn Off 108.1 while the
modem is in the data mode, the modem will hang up and disconnect.
The ITU-T V.25 bis compatible command set is not available when the
modem is operating in 108.1 mode. Storage of a telephone number in
memory cell 0 must be performed either in 108.2 mode (using the PRN
command), or by means of AT commands.
Any number can be called in 108.1 mode by dialing manually and then
turning On circuit 108.1 when answer tone is heard from the remote
modem.
Operating Procedures
Refer to the ITU-T V.25 bis Command Set Communication Operating
Procedures below for a full description of the communication
procedures for the 108.2 and 108.1 modes.
Refer to Synchronous V.25 bis Interface Specifications below for
synchronous dialing protocol formats.
Commanding The Modem
Although the AT command set is the primary command set for
configuring the modem, the modem provides an enhanced ITU-T V.25
bis command protocol that permits you to configure modem dial
parameters and establish data communications. After configuring the
modem using the AT command set, use the %Vn command to switch
to the V.25 bis command set.
Table 5-1 summarizes the V.25 bis compatible command set. When
entering commands, terminate each one with a line feed <LF> control
character. The modem sends a response back to the terminal for each
command. Table 5-2 explains responses to valid commands. Table 5-3
explains responses to invalid commands. Most terminals display the
responses to indicate each entered command's result, but responses are
ignored by some communications software that enables a computer to
emulate a terminal.
Descriptions of each V.25 bis 108.2 mode command appear on the
following pages.
Operating procedures for establishing and terminating data
communications are explained following the command descriptions.
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Table 5-1
V.25 bis Command Set Summary
Configuration Commands
Name
Cmd.
Page
Write Option Settings to User Configuration Profile
NVW
5-5
Store Phone Number to Cell
PRN
5-5
Automatic Answering
PRS AA
5-5
AT Command Set
PRS AT
5-6
Connect Message Inhibit
PRS CM
5-6
DTE Data Rate
PRS DR
5-6
Handshake Mode
PRS HM
5-8
Termination Character
PRS TR
5-8
Synchronous Timing
PTM
5-9
Communication Commands
Name
Cmd.
Page
Connect Incoming Call
CIC
5-9
Call Requested Number
CRN
5-9
Call Requested Stored Telephone Number
CRS
5-11
Disconnect Incoming Call
DIC
5-11
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Table 5-2
Response
Explanation of Valid Responses
Description
CFI AB
Call failure indication: no carrier, call was aborted (time-out occurred
or character was entered at keyboard).
CFI BF
Call failure indication: telephone number black list (which uses the 10
memory cells) is full. You cannot place any more calls until: a) after a
timeout; b) the memory cell is modified; or c) the modem is reset.
CFI ET
Call failure indication: remote modem is busy.
CFI DT
Call failure indication: dial tone was not detected (dial tone time-out
occurred).
CFI DF
Call failure indication: telephone number delayed list (which uses the
10 memory cells) is full. Numbers which are redialed continuously
without making a connection are added to the delayed list. They are
removed from the list: a) after a timeout; b) when a connection is
made; c) when the memory cell is modified; or d) when the modem is
reset.
CFI UT
Call failure indication: unobtainable number tone was detected.
CNX
300 bps connection is established.
CNX 1200
1200 bps connection is established.
CNX 2400
2400 bps connection is established.
CNX 4800
4800 bps connection is established.
CNX 7200
7200 bps connection is established.
CNX 9600
9600 bps connection is established.
CNX 12000
12,000 bps connection is established.
CNX 14400
14,400 bps connection is established.
CNX 16800
16,800 bps connection is established.
CNX 19200
19,200 bps connection is established.
CNX 21600
21,600 bps connection is established.
CNX 24000
24,000 bps connection is established.
CNX 26400
26,400 bps connection is established.
CNX 28800
28,800 bps connection is established.
INC
Incoming call was detected. This response is generated only once for
each incoming call.
INV
See Table 5-3 for responses to commands that the modem does not
recognize.
RNGBK
Ringback was detected by the originating modem.
VAL
Valid command was invoked.
5-4
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Table 5-3
Explanation of Invalid Responses
Command Invoked
Description of INV Response
DIC
INC not received.
PRS
Non-selectable option in user's country.
V.25 bis Configuration Commands
Configuration commands allow you to configure the modem.
NVW
Write Option Settings to User Configuration Profile
NVW saves the current settings to a user configuration profile in
the modem's non-volatile memory, with the exception of the
Terminator Character option (which is set to its factory default,
the line feed control-character). This command saves a set of
option values that is activated when the modem is powered up.
To invoke this command, type:
NVW ; n <LF>
where n is the user configuration profile (0 to 3).
PRN
Store Phone Number to Cell
PRN stores a telephone number in one of the modem's ten
memory cells. Use it to store the number that is automatically
dialed when you either invoke the CRS command in 108.2 mode
or turn On circuit 108.1 in 108.1 mode (108.1 dialing uses the
number stored in memory cell 0).
To store a number, type:
PRN n1 ; n2 <LF>
where n1 is the memory cell (from 0 to 9) in which the number is
to be stored, and n2 is the phone number to be stored. n2 may
contain any legal dialing character (0-9 A-D P T # * , < ! & @).
PRS AA
Automatic Answering
PRS AA controls the automatic answering function. When you
enable automatic answering, you can specify the number of rings
the modem is to wait before automatic answering occurs. Default
is 4 rings.
To enable automatic answering, type:
PRS AA ; n <LF>
where n is the number of rings (from 1 to 255) that the modem
waits before automatically answering an incoming call.
To disable automatic answering, type
PRS AA ; 0 <LF>
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PRS AT
AT Command Set
PRS AT switches the modem from V.25 bis command set mode
to AT command set mode.
To return to V.25 bis command set mode, use the %Vn AT
command.
To invoke this command, type:
PRS AT <LF>
PRS CM
Connect Message Inhibit
PRS CM controls the CNX yy connect message responses. The
V.F 28.8/33.6 supports both the 1989 and the 1984
recommendations for V.25 bis connection procedures. The 1989
CCITT Blue Book recommends that when the modem transfers
from command mode to data mode it should send a connect
message of the form CNX yy, where yy identifies the connect
speed (96 = 9600 bps, 48 = 4800 bps, 24 = 2400 bps, and 12 =
1200 bps; omitted for 300 bps). The 1984 CCITT Red Book does
not include these connect messages. Default is 0 (connect
message disabled).
To disable the CNX yy connect message responses, type:
PRS CM ; 0 <LF>
To enable responses, type:
PRS CM ; 1 <LF>
Note
PRS DR
After modifying this option you should save the setting by using
the NVW command.
DTE Data Rate
PRS DR, in conjunction with the hand-shake mode command
(PRS HM), controls the DTE speed. There are several
configurations to consider:
a. An automatic handshake mode (e.g., V.32 bis auto [PRS HM
; 2], V.32 auto [PRS HM ; 4], V.22 bis only [PRS HM ; 6])
takes precedence over the PRS DR selection, and the
modem tries for the highest VF speed common to the two
commands.
b. For 1200 bps V.22 operation, select PRS HM ; 7. PRS HM ;
6 is an auto mode, so setting the DTE to 1200 bps
(PRS DR ; 3) will not force the connection to 1200 bps.
c. When the modem is optioned for an automatic hand-shake
mode and direct V.14 asynchronous mode (AT command
\N1), it sends a connect message to the DTE at the selected
PRS DR speed. In order to pass data, the user must change
the DTE's speed to match the displayed connect speed.
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d.
e.
f.
Note
When the modem is optioned for speed buffering (AT
command \N0) or an error correcting protocol (AT
commands \N3 or \N4), the PRS DR command alone selects
the DTE speed, and the PRS HM command selects the
hand-shake mode.
When the modem is optioned for a fixed handshake mode
and direct mode (AT command \N1), the PRS DR command
selects not only the DTE speed, but also forces the VF
speed to match it. If this speed is not available, the modem
drops the call. (This does not apply to V.22 bis only, which
handshakes at the highest VF speed.)
When using the modem in direct mode (AT command \N1), if
the desired connect speed is known, set the speed to match
using the PRS DR command. Set the DTE to the same
speed and "AT" the modem so that it will know at what speed
to send messages.
The modem must be in the AT command set mode in order to
configure the \Nn AT command.
To invoke this command, type:
PRS DR ; n <LF>
where n is the DTE rate, as follows:
n rate
n
0 Autobaud
11
1 Last connect speed
12
2 300 bps
13
3 1200 bps
14
4 2400 bps
15
5 4800 bps
16
6 7200 bps
17
7 9600 bps
18
8 12,000 bps
19
9 14,400 bps
20
10 16,800 bps
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rate
19,200 bps
21,600 bps
24,000 bps
26,400 bps
28,800 bps
38,400 bps
57,600 bps
76,800 bps
115,200 bps
128,000 bps
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PRS HM
Handshake Mode
PRS HM selects the handshake mode.
Note
a.
b.
When the modem is optioned for an external transmit clock
source (PTM ; 1), the modem should be optioned for a fixed
hand-shake mode, not an automatic hand-shake mode (e.g.,
select V.32 bis only [PRS HM ; 3] instead of V.32 bis
automatic [PRS HM ; 2]). The modem will then handshake
only at the speed given to it by the DTE.
For 1200 bps V.22 operation, select PRS HM ; 7. PRS HM ; 6
is an auto mode, so setting the DTE to 1200 bps (PRS DR ;
3) will not force the connection to 1200 bps.
To invoke this command, type:
PRS HM ; n <LF>
where n is the handshake mode, as follows:
n mode
0 V.34 auto (28.8 kbps to 300 bps)
1 V.34 only (28.8 kbps to 9600 bps)
2 V.32 bis automatic (14.4 kbps to 300 bps)
3 V.32 bis only (14.4 kbps to 4800 bps)
4 V.32 automatic (9600 bps to 300 bps)
5 V.32 only (9600 bps to 4800 bps)
6 V.22 bis only (2400 bps to 1200 bps)
7 V.22 only (1200 bps)
8 Bell 212 only (1200 bps)
9 Bell 103 only (300 bps)
10 V.21 only (300 bps)
PRS TR
Termination Character
PRS TR selects the ASCII character that represents the
command termination character in the asynchronous mode. The
command termination character is the character that is used to
enter a command for interpretation by the modem. Select the
command termination character that is compatible with your
preference and your terminal. Default is 10 or <LF> (line feed).
To select the line feed control-character as the command
termination character, type:
PRS TR ; 10 <LF>
To select the vertical tabulation control-character, type:
PRS TR ; 11 <LF>
To select the form feed control-character, type:
PRS TR ; 12 <LF>
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PTM
Synchronous Timing
PTM selects the clock source when operating in a synchronous
data mode.
To select internal clock (supplied by the modem), type:
PTM ; 0 <LF>
To select external clock (supplied by the DTE), type:
PTM ; 1 <LF>
To select receiver wrap clock (derived from received data), type:
PTM ; 2 <LF>
V.25 bis Communication Commands
Communication commands allow you to establish and terminate data
communications.
CIC
Connect Incoming Call
CIC causes the modem to automatically answer the current
incoming call. Use it to temporarily modify the automatic
answering function (the modem answers the call after accepting
CIC, ignoring the number of automatic answering rings selected
with the PRS AA command). Ten seconds after one incoming call
is completed, normal automatic answering is restored.
To invoke this command, type:
CIC <LF>
CRN
Call Requested Number
CRN causes the modem to dial a telephone number, supplied
with the command, to initiate data communication with another
modem. If the handshake abort timer (AT command S7=x) times
out before the modem detects answer tone, the modem will
return on-hook.
To invoke this command, type:
CRN n <LF>
where n is the telephone number to be dialed. The modem
recognizes only the characters contained in n that are listed in
Table 5-4. To dial 555-1234, for example, type:
CRN 5551234 <LF>
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Table 5-4
Legal Dialing Characters
Character
Description
0 1 2 3 4 5 6 7 8 or 9
Pulse and tone dial digits
#
Tone dial character
*
Tone dial character
P
Causes dialed numerals following P to be dialed using
pulses. Used to select pulse dialing for compatibility with your
telephone system. Pulse dialing is blocked by some country
code configurations.
T
Causes dialed alphanumeric characters following T to be
dialed using tones. Used to select tone dialing for
compatibility with the telephone system you intend to use.
, or <
Causes the modem to pause a specified length of time
before dialing the next digit of a telephone number (the
pause is 2 seconds in length by default and may be changed
with the S8=x AT command). Used when the telephone
system requires a pause before it can accept the next digit of
the telephone number being dialed.
! or &
Causes the modem to go on-hook (flash) momentarily. Used
to command certain internal telephone systems (PBXs).
@
Causes the modem to wait n seconds for one or more rings
followed by five seconds of silence be-fore dialing the next
digit of a telephone number (if n seconds expire before a ring
is detected, the modem will abort dialing and return to the
command mode). Used to dial a telephone system that does
not provide dial tone. Silence, rather than dial tone, indicates
that the telephone system is ready to accept telephone
number dialing. (n = the value selected in the abort timer.)
Ln
On dial failure, link to the telephone number stored in cell n (n
= 0 to 9).
W or :
Causes the modem to wait a specified length of time for dial
tone before dialing the next digit of the telephone number.
The length of time is specified by the S7=x AT command. If
this time expires before dial tone is detected, the modem will
abort dialing and return to the command line.
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CRS
Call Requested Stored Telephone Number
CRS causes the modem to dial the telephone number stored in a
specified modem memory cell. The number to be dialed must
have been stored in a memory cell previously by means of the
PRN command.
To invoke this command, type:
CRS n <LF>
where n is the number (from 0 to 9) of the memory cell containing
the telephone number to be dialed. To dial the number stored in
memory cell 5, for example, type:
CRS 5 <LF>
DIC
Disconnect Incoming Call
DIC causes the modem to temporarily disable the automatic
answering function and ignore an incoming call. Ten seconds
after one incoming call is completed, normal automatic
answering is restored.
To invoke this command, type:
DIC <LF>
ITU-T V.25 bis Command Set Operating Procedures
The following paragraphs describe communication operating
procedures for the V.F 28.8/33.6 using the ITU-T V.25 bis command
set. The descriptions include procedures for originating, answering,
and terminating a call in the 108.2 and 108.1 modes.
108.2 Mode Operating Procedures
The following communication operating procedures are intended for
the 108.2 mode.
Originating a Call
To establish communication by originating a call in the 108.2 mode:
1.
From the DTE, use the CRN or CRS command to dial the desired
telephone number.
2.
When communication is established, your terminal displays the
CNX response (if enabled with the PRS CM ; 1 command) and
you may transfer data.
Automatic Call Answering
To have the modem automatically answer calls and establish
communication:
1.
Enable automatic answering by typing:
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PRS AA ; n <LF>
where n is the number of rings (from 1 to 255) that the modem will
wait before it performs automatic answering. The default is 4.
2.
The modem will answer any incoming call automatically after
the specified number of rings.
3.
When communication is established, your terminal will display
the CNX response and data transfer can take place. If
communication is not established, your terminal will display the
appropriate response and the modem will return to the command
mode.
Manual Call Answering
The command PRS AA ; 0 <LF> disables automatic call answering.
When automatic answering is disabled, use the following procedure to
establish communication by manually answering calls:
1.
When your terminal displays the INC result code to indicate an
incoming call, type:
CIC <LF>
2.
When communication is established, your terminal will display
the CNX response and data transfer can take place. If
communication is not established, your terminal will display the
appropriate response and the modem will return to the command
mode.
Automatic Call Termination
The modem will automatically terminate a call
5-12
a.
if terminal interface signal 108.2 (DTR) is turned Off while the
modem is in data mode. This mode of automatic termination
functions only when DTR is optioned for normal operation; it is
disabled if 108.2 is optioned for forced On operation.
b.
if the handshaking sequence is not completed within the abort
time period (selected by the S7=x AT command; default is 30
seconds) after originating or answering a call.
c.
if a long space is received and long space disconnect has been
enabled by the Yn AT command. This mode of automatic
termination functions only when the modem is operating at 300,
1200, or 2400 bps.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
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108.2 Call Establishment Procedure
The general principle for establishing a call between the DTE and DCE
complies with the V.25 bis 108.2 mode of operation and is outlined
below:
Originating a Call
DTE
DCE
Turn On DTR.
Turn On CTS.
Send Command: CRN or CRS.
Send VAL response.
Dial phone number.
Wait for the connection (or abort the
call by turning Off DTR).
Turn Off CTS when answer tone is
detected or send CFI response in
cases where the call has failed.
Turn On DSR and DCD when handshake is successful.
Recognizes successful connection
when DSR comes On.
Recognizes connected data rate from
the CNX message.
Send connect CNX message.
Enter data transfer mode.
Turn On RTS to send data.
CTS responds to RTS.
Turn Off DTR to terminate call.
Disconnect from line.
Turn Off CTS, DSR, and DCD.
Send CFI call abort message.
054R207-000
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V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
5-13
Answering a Call
DTE
DCE
Turn On DTR.
After detection of an incoming ring,
send INC message.
When Auto Answer is enabled,
modem will answer call after preset
number of rings if DTR is On.
The CIC command is not required.
Send CIC command to permit
answering, or send DIC command to
disregard the incoming ring.
Disregard incoming ring if DIC is
received.
Answer call after the next ring if CIC is
received.
At next ring, go off-hook.
Turn Off CTS.
Turn On DSR and DCD when going
through handshake successfully.
Recognizes successful connection
when DSR comes On.
Send connect CNX message.
Go into data transfer mode.
Recognizes connected data rate from
the CNX message.
CTS responds to RTS.
Turn On RTS to send data.
Turn Off DTR to terminate call.
Disconnect from line.
Turn Off CTS, DSR, and DCD.
Send CFI call abort message.
108.1 Mode Operating Procedures
The following communication operating procedures are intended for
the 108.1 mode.
Originating a Call Automatically
To establish communication by automatically originating a call in the
108.1 mode:
5-14
1.
Prior to the time of calling a telephone number must be stored in
the modem's memory cell 0. That can be done with either the
108.2 mode PRN command or the AT command &Zn=nnn.
2.
To initiate an automatically dialed call in 108.1 mode, turn On
terminal interface circuit 108.1.
3.
When communication is established with the remote modem, you
may transfer data.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Originating a Call Manually
To establish communication by manually originating a call:
1.
Lift the telephone handset, listen for a dial tone, and call the
remote site.
2.
When calling an automatically answered site, turn On terminal
interface circuit 108.1 - or press the TALK/DATA switch on the
front panel - when you hear answer tone.
3.
When calling a manually answered site, ask the attendant who
answers the call to transfer the remote modem to data mode.
When you hear answer tone, turn On terminal interface circuit
108.1 - or press the TALK/DATA switch.
4.
When communication is established, you may transfer data.
Automatic Call Answering
The modem can answer calls automatically in 108.1 mode if the
function has not been disabled. The automatic answer enable/disable
command (in 108.2 mode) is
PRS AA ; n <LF>
where n is the number of rings (from 1 to 255) that the modem will
wait before it begins the automatic answering process.
PRS AA ; 0 <LF> disables automatic answering. The default is 4.
The following sequence of events takes place when the modem senses
an incoming call:
1.
After the specified number of rings, the modem turns On circuit
125 (Call Indicator) to alert the DTE that an incoming call is
trying to make a connection.
2.
If the DTE is prepared to accept the connection it responds by
turning On circuit 108.1. While Call Indicator is On, circuit 108.1
acts as the command to perform automatic answering.
3.
The modem then goes off-hook, performs handshaking, and,
when that is successfully completed, begins data transfer with the
remote modem.
Manual Call Answering
When automatic answering is disabled, use the following procedure to
establish communication by manually answering calls:
1.
When the telephone rings, lift the handset.
054R207-000
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V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
5-15
2.
When the remote site attendant asks you to place the modem in
data mode, turn On terminal interface 108.1 - or press the
talk/data switch (D/TK key) on the front panel.
3.
Hang up the handset. You may now commence data communications.
Terminating a Call
To terminate communication, turn Off terminal interface circuit 108.1
or press the TALK/DATA switch.
V.25 bis 108.2 Mode Interface Specifications
Physical connections between a DTE and a DCE may be either
synchronous or asynchronous. The ITU-T V.25 bis 108.2 mode
recommendations describe the exchange of commands and responses
between the units using both types of operation. The V.F 28.8/33.6
supports command/response exchange in either mode.
The following paragraphs describe the functional characteristics of the
V.25 bis synchronous and asynchronous interfaces, as used in the V.F
28.8/33.6 modem.
Interface Connections
From DCE to DTE:
From DTE to DCE:
5-16
104
RXD
106
CTS
107
DSR
125
Call Indicator/Ring Detector
114
TX Timing (synchronous only)
115
RX Timing (synchronous only)
103
TXD
105
RTS
108.2
DTR
113
TX Timing (synchronous only)
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
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Synchronous Format Selection
The V.F 28.8/33.6 supports both the bit-oriented and the byte-oriented
modes of synchronous operation.
Synchronous Bit-Oriented Operation
The modem uses the HDLC format in the bit-oriented synchronous
mode (%V2 AT command). The structure of each message in this
format is shown below:
Å Time
F
FCS
Message
C
A
F
F
=
Idle Flag (01111110)
FCS
=
Frame Check Sequence (CRC-ITU-T, x16+x12+x5+1)
Message
=
Command/Response (7-bit ASCII data and 1 odd parity)
C
=
Control (00010011*)
A
=
Address (11111111*)
*The modem will not recognize the C or A fields unless verified as shown
above.
Synchronous Byte-Oriented Operation
The modem uses the BISYNC (BSC) format in the byte-oriented
synchronous mode (%V3 AT command). The structure of each
message in this format is shown below:
Å Time
BCC
ETX
Message
STX
BCC
=
LRC Block Check Character for ASCII
ETX
=
ASCII ETX Character (10000011)
SYN
SYN
Message
=
Command/Response (7-bit ASCII data and 1 odd parity)
STX
=
ASCII STX Character (00000010)
SYN
=
ASCII SYN Character (00010110)
Note
054R207-000
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BCC is always transmitted in the modem's responses, but
optionally included in the DTE commands. In this way, the modem
conforms to BSC conventions without deviating from the ITU-T
V.25 bis Recommendations.
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
5-17
Data Rate
The V.F 28.8/33.6 does not support 300 bps in the synchronous mode.
Also, in the synchronous mode, the modem will not hand-shake with
an incoming call at 300 bps FSK.
Asynchronous Format
The structure of each message in the asynchronous mode (%V1 AT
command) format is shown below:
Å Time
OFF
LF
Message
OFF
OFF
=
Interface idle
Message
=
Command/Response (10-bit characters: 1 start, 7-bit
ASCII data, 1 even parity, 1 stop)
LF
=
ASCII Line Feed Character (00001010)
Modem Test Modes
When optioned to operate in the synchronous V.25 bis mode, the V.F
28.8/33.6 supports the following test modes that can be initiated from
the front panel:
•
Analog Loopback
•
Analog Loopback with Self-Test
•
Digital Loopback
•
Remote Digital Loopback
•
Remote Digital Loopback with Self-Test
•
End-to-End Self-Test
All tests may be terminated from the front panel switches, and the
modem returns to off-line idle command state when DTR goes from On
to Off. Pending tests can be cleared only from the front panel.
5-18
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Chapter 6: Tests
Overview
This section describes tests that can be invoked to isolate a trouble
condition. The tests can isolate a problem to the data connection, data
set operation, or the DTE interface level. Refer to Table 6-1 for a
sequence of tests for fault isolation.
Note
a.
b.
c.
054R207-000
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On-line tests, which involve data transmitted from one
modem to another, can be performed with the modems
operating in either synchronous mode or direct (N1)
asynchronous mode. They cannot be initiated until the
modem has been in data mode for approximately 30 seconds.
Once a modem is in Slave RDL, it will ignore all requests
other than AL.
If an RDL request does not get a response from the Slave
modem at 2400 bps, the Master will drop the line.
V.F 28.8/33.6 ModemDeskTop Platform
Installation and Operation
6-1
Start
Perform
Analog Loopback
with Self-test
Local Modem
Problem
Local Terminal or
Local Terminal-Modem
Connection Problem
Fail
Fail
Local Modem
Problem
Fail
Figure 6-1
or
Pass
Pass
or
Pass
or
Perform Remote
Digital Loopback
with Self-test
Pass
Perform Local
Digital Loopback
with Self-test
Fail
Pass
or
Perform
Analog Loopback
Pass
Fail
Fail
Pass
or
Fail
Pass
Fail
Perform Remote
Digital Loopback with
Self-test at Remote Modem
Communication
Line Problem
6-2
Fail
Pass
Fail
Communication
Line Problem
Pass
Remote Terminal or
Remote Terminal-Modem
Connection Problem
Fault Isolation Sequence
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Analog Loopback
The analog loopback (ANALOOP) test mode is provided to isolate
problems in the data set operation and the DTE interface. Specifically,
ANALOOP tests modem modulator/demodulator operation, DTE
receive/transmit operation, and DTE interface operation. The
ANALOOP test can be controlled from the front panel or by AT
commands.
Note
When the modem is used in \N0, \N3, \N4, or \N5 modes with a
fixed DTE speed, it will not issue a CONNECT message. When the
modem is used in \N1 mode, since the ANALOOP handshake
speed may not match the DTE speed selected, the modem will
issue a CONNECT _ _ _ _ message at the last known DTE rate. If
the DTE rate and handshake rate differ, the user can change the
DTE to match the rate reported by the CONNECT message.
Local Modem
DTE
Table 6-1
Step
Send Data
Modem
Transmitter
Receive Data
Modem
Receiver
Analog Loopback
Front Panel
AT Command Mode
1.
Press DIAG, then scroll to
ANALOOP and press ENTER.
Type: AT&T1 (enter). If modem
responds with an error message, type:
AT%T0 (enter), which resets the test
mode, then re-enter the command.
2.
The modem flashes the TM LED
and displays the test name (LL)
while it is setting up the test, then
lights the TM LED and decimal point
three while the test is running.
The modem flashes the TM LED while
it is setting up the test, then lights the
TM LED and decimal point three while
the test is running.
3.
Enter test data at DTE. Compare the data that was entered at the DTE with
the data that is looped back and displayed by the DTE. If errors occur
frequently, a problem may exist in the modem, DTE or DTE-to-modem
connection. Refer to the fault-isolation diagram to isolate the problem.
4.
To end test, press DIAG, then scroll
to CANCEL TEST and press
ENTER.
054R207-000
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To end test, type the escape sequence
(+++) and, after the modem is in the
command mode, type: AT&T (enter)
V.F 28.8/33.6 ModemDeskTop Platform
Installation and Operation
6-3
Analog Loopback With Self-Test
ANALOOP may be combined with Self-Test. Upon initiation of SelfTest, a pattern is generated by the transmitter and sent to the receiver
for analysis. The pattern is made up of alternate ones and zeros for
speeds of 1200 and 2400 bps. For all other speeds the modem generates
a 511 test pattern. The number of errors is displayed on the LCD screen.
This test provides a means for the customer to determine whether the
problem is in the local data set.
This test is not operational when the modems are passing data at 300
bps.
Table 6-2
Step
Analog Loopback With Self-Test
Front Panel
AT Command Mode
1.
Press DIAG, then scroll to
ANALOOP SELFTEST and press
ENTER.
Type: AT&T9 (enter). If modem
responds with an error message, type:
AT%T0 (enter), which resets the test
mode, then re-enter the command.
2.
The modem flashes the TM LED
and displays the test names (LL
and ST) while it is setting up the
test, then lights the TM LED and
displays four digits of the error
count (0000 to 9999) while the test
is running. It indicates larger
numbers by lighting decimal point
one and displaying the four least
significant digits of the actual count
(for example, the actual error count
is 12345, but the modem displays
2.345).
The modem flashes the TM LED while
it is setting up the test, then lights the
TM LED while the test is running.
When the test is terminated, the
screen displays a four-digit number
corresponding to the number of errors
detected during the test, followed by
the OK message. Any number greater
than 0 indicates the modem has failed
the test.
3.
If the timer, S-Register 18, is set to a value between 1 and 60, the test ends
automatically after that value (in 10-second increments) is reached. The
factory default for S-Register 18 is 000, meaning that the test will continue
indefinitely.
4.
To end test manually, press DIAG,
then scroll to CANCEL TEST and
press ENTER.
6-4
To end test manually, type the escape
sequence (+++) and, after the modem
is in the command mode, type: AT&T
(enter)
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Digital Loopback
The modem can be commanded to enter digital loopback, illustrated in
Table 6-3, by means of the front panel or AT commands. This loopback
is used while a call to the distant modem is established. In digital
loopback the local received data is coupled to the transmitter input so
that the remote unit can perform a loopback test without commanding
remote loopback.
In asynchronous mode the clocks will be clamped at the EIA interface.
DTE
Local Modem
Modem
Transmitter
Modem
Receiver
Table 6-3
Step
Remote Modem
Modem
Receive
Receiver
DTE
Data
Send
Data
Modem
Transmitter
Digital Loopback
Front Panel
AT Command Mode
1.
Establish data communications with a remote modem.
2.
To start the test, press DIAG, then
scroll to DIGITAL LOOPBACK and
press ENTER.
To start the test, type the escape
sequence (+++) and, after the modem
is in the command mode, type: AT&T3
(enter). If modem responds with an
error message, type: AT%T0 (enter),
which resets the test mode, then reenter the command.
3.
The modem flashes the TM LED
and displays the test name (DL)
while it is setting up the test, then
lights the TM LED and decimal
point one while the test is running.
The modem flashes the TM LED while
it is setting up the test, then lights the
TM LED and decimal point one while
the test is running.
4.
Direct the remote attendant to enter data at the remote DTE and then
compare it with the data that is looped back and displayed by the DTE. If
errors occur frequently, a problem may exist in the local or remote modems,
the remote DTE, the remote DTE-to-modem connection, or the
communication line. Refer to the fault isolation diagram to isolate the
problem.
5.
To end the test, press DIAG, then
scroll to CANCEL TEST and press
ENTER.
054R207-000
Issue 11
To end the test, type: AT&T0 (enter)
then type ATO (enter) to go back on
line.
V.F 28.8/33.6 ModemDeskTop Platform
Installation and Operation
6-5
Remote Digital Loopback
Remote Digital Loopback, illustrated in Table 6-4, is controlled at the
local end. It can be commanded from the front panel, or with AT
commands, or by the DTE's EIA pin 21. The loopback can be
commanded only after a call is established and both ends are in data
mode. In this loop, the demodulator's descrambled received data at the
remote end is coupled to the remote transmitter input for transmission
back to the local end.
This test is not operational when the modems are passing data at 300
bps.
Note
This test cannot be performed if the remote modem is commanded to ignore a remote digital loopback command.
If the modems are operating at V.22 bis speeds and the local
modem issues the RDL command to a remote unit configured to
ignore the remote loop-back command, the resulting condition
will cause the local modem to drop the connection.
Local Modem
DTE
Modem
Transmitter
Send
Data
Receive
Data
Table 6-4
Step
Modem
Receiver
Remote Modem
Modem
Receive
Receiver
DTE
Data
Send
Data
Modem
Transmitter
Remote Digital Loopback
Front Panel
AT Command Mode
1.
Establish data communications with a remote modem.
2.
Check with the remote attendant that the remote modem will accept Remote
Digital Loopback commands.
3.
To start the test, press DIAG, then
scroll to RDL and press ENTER.
To start the test, type the escape
sequence (+++) and, after the modem
is in the command mode, type: AT&T6
(enter). If modem responds with an
error message, type: AT%T0 (enter),
which resets the test mode, then reenter the command.
(Sheet 1 of 2)
6-6
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Table 6-4
Step
Remote Digital Loopback (Continued)
Front Panel
AT Command Mode
4.
The modem flashes the TM LED
and displays the test name (RL)
while setting up the test, then lights
the TM LED and decimal point two
while the test is running. (If the
remote modem initiated the test,
the local modem lights decimal
points three and four while the test
is running.)
The modem flashes the TM LED while
it is setting up the test, then lights the
TM LED and decimal point two while
the test is running. (If the remote
modem initiated the test, the local
modem lights decimal points three
and four while the test is running.)
5.
Enter data at the local DTE. Compare the data that was entered at the DTE
with the data that is looped back and displayed by the DTE. If errors occur
frequently, a problem may exist in the local or remote modems, the local
DTE, the local DTE-to-modem connection, or the communication line. Refer
to the fault-isolation diagram to isolate the problem.
6.
To end the test, press DIAG, then
scroll to CANCEL TEST and press
ENTER.
Note:
Note:
To end the test, type the escape
sequence (+++) and, after the modem
is in the command mode, type: AT&T0
(enter) then type ATO (enter) to go
back on line.
Any attempt to terminate the test at the remote modem by using the
AT&T0 command will cause the modem to disconnect from the line.
CTS at the remote modem will drop low during the test.
(Sheet 2 of 2)
Remote Digital Loopback With Self-Test
Remote Digital Loopback with Self-Test is controlled at the local end.
It can be commanded from the front panel or with AT commands. This
command can only be entered after the call is established and both ends
are in the data mode. The test causes the local modem to generate a
pattern that is transmitted across the telephone line to the remote
modem's receiver, looped through to the remote modem's transmitter,
and sent back across the telephone line to the local modem's receiver
for analysis. The pattern is made up of alternate ones and zeros for
speeds of 1200 and 2400 bps. For all other speeds the modem generates
a 511 test pattern. The number of errors is displayed on the LCD
screen. This test checks both modems and the telephone line.
This test is not operational when the modems are passing data at 300
bps.
Note
054R207-000
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This test cannot be performed if the remote modem is commanded
to ignore a remote digital loopback command.
V.F 28.8/33.6 ModemDeskTop Platform
Installation and Operation
6-7
Table 6-5
Step
Remote Digital Loopback With Self-Test
Front Panel
AT Command Mode
1.
Establish data communications with a remote modem.
2.
Check with the remote attendant that the remote modem will accept Remote
Digital Loopback commands.
3.
To start the test, press DIAG, then
scroll to RDL SELFTEST and press
ENTER.
To start the test, type the escape
sequence (+++) and, after the modem
is in command mode, type: AT&T7
(enter). If modem responds with an
error message, type: AT%T0 (enter),
which resets the test mode, then reenter the command.
4.
The modem flashes the TM LED
and displays the test names (RL
and ST) while it is setting up the
test, then lights the TM LED and
displays four digits of the error
count (0000 to 9999) while the test
is running. It indicates larger
numbers by lighting decimal point
one and displaying the four least
significant digits of the actual count
(for example, the actual error count
is 12345, but the modem displays
2.345).
The modem flashes the TM LED while
it is setting up the test, then lights the
TM LED while the test is running.
When the test is terminated, the
screen displays a four-digit number
corresponding to the number of errors
detected during the test, followed by
the OK message.
5.
If the timer, S-Register 18, is set to a value between 1 and 60, the test ends
automatically after that value (in 10-second increments) is reached. The
factory default for S-Register 18 is 000, meaning that the test will continue
indefinitely.
6.
To end the test manually, press
To end the test manually, type the
DIAG, then scroll to CANCEL TEST escape sequence (+++) and, after the
and press ENTER.
modem is in the command mode,
type: AT&T0 (enter) then type ATO
(enter) to go back on line.
6-8
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
End-to-End Self-Test
End-to-End Self Test requires operators at both the local and remote
modem. It can be commanded from the front panels or with AT
commands. The commands can only be entered after the call is
established and both ends are in the data mode. The test causes each
modem to generate a pattern and to transmit it to the other modem. The
modem receiving the pattern checks it for errors. The patterns are made
up of alternate ones and zeros for speeds of 1200 and 2400 bps. For all
other speeds the modems generate a 511 test pattern. The number of
errors received is displayed on the screen. This test checks the
operation of both modems and the communications line.
This test is not operational when the modems are passing data at 300
bps.
Table 6-6
Step
End-To-End Self-Test
Front Panel
AT Command Mode
1.
To start the test at each modem,
press DIAG, then scroll to
SELFTEST and press ENTER.
To start the test, at each modem type:
AT&T9 (enter). If modem responds
with an error message, type: AT%T0
(enter), which resets the test mode,
then re-enter the command.
2.
The modem flashes the TM LED
and displays the test name (ST)
while it is setting up the test, then
lights the TM LED and displays four
digits of the error count (0000 to
9999) while the test is running. It indicates larger numbers by lighting
decimal point one and displaying
the four least significant digits of the
actual count (for example, the
actual error count is 12345, but the
modem displays 2.345).
The modem flashes the TM LED while
it is setting up the test, then lights the
TM LED while the test is running.
When the test is terminated, the
screen displays a four-digit number
corresponding to the number of errors
detected during the test, followed by
the OK message. Any number greater
than 0 indicates the modem has failed
the test.
3.
If the timer, S-Register 18, is set to a value between 1 and 60, the test ends
automatically after that value (in 10-second increments) is reached. The
factory default for S-Register 18 is 000, meaning that the test will continue
indefinitely.
4.
To end the test manually at each
modem, press DIAG, then scroll to
CANCEL TEST and press ENTER.
054R207-000
Issue 11
To end the test, type the escape
sequence (+++) at each modem and,
after the modem is in the command
mode, type: AT&T0 (enter).
V.F 28.8/33.6 ModemDeskTop Platform
Installation and Operation
6-9
RDLB Requests
Your modem is factory set to acknowledge a remote modem’s request
to participate in a remote digital loopback test initiated from the remote
location. If you do not want to acknowledge such requests, enter
AT&T5&W.
If you later decide to acknowledge such requests enter AT&T4&W.
Maintenance
The V.F 28.8/33.6 modem is designed to operate without maintenance.
Certain steps should, however, be taken in order to assure that the
modem will continue to operate without problem.
Connections
Periodically check to make sure that all of the modem connections are
secure.
Cleaning
If the modem enclosure becomes dirty, it should be cleaned with a
damp cloth. If necessary, add a drop of liquid soap to the cloth, but do
not use cleansers, ammonia, or cleaning solvents as they can harm the
enclosure.
054R207-000
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V.F 28.8/33.6 ModemDeskTop Platform
Installation and Operation
6-10
Appendix A: Technical
Characteristics
Item
Specification
VF Data Rate
33.6 kbps (ITU-T V.34)
Synchronous/asynchronous
31.2 kbps (ITU-T V.34)
Synchronous/asynchronous
28.8 kbps (ITU-T V.34)
Synchronous/asynchronous
26.4 kbps (ITU-T V.34
Synchronous/asynchronous
24.0 kbps (ITU-T V.34)
Synchronous/asynchronous
21.6 kbps (ITU-T V.34)
Synchronous/asynchronous
19.2 kbps (ITU-T V.34)
Synchronous/asynchronous
16.8 kbps (ITU-T V.34)
Synchronous/asynchronous
14.4 kbps (ITU-T V.34 or V.32 bis)
Synchronous/asynchronous
12.0 kbps (ITU-T V.34 or V.32 bis)
Synchronous/asynchronous
9600 bps (ITU-T V.34, V.32 bis, or V.32)
Synchronous/asynchronous
7200 bps (ITU-T V.34, V.32 bis)
Synchronous/asynchronous
4800 bps (ITU-T V.34, V.32 bis, or V.32)
Synchronous/asynchronous
2400 bps (ITU-T V.34 or V.22 bis)
Synchronous/asynchronous
1200 bps (ITU-T V.22 or Bell 212A)
Synchronous/asynchronous
300 bps (ITU-T V.21 or Bell 103))
Asynchronous only
Data Format
Bit synchronous
Bit asynchronous
Selectable 8, 9, 10, or 11 bits per
character
Transmit Clock
Internal, External, or Receive Wrap
Compatibility
ITU-T V.34, V.32 bis, V.32, V.22 bis,
V.22, V.21, Bell 212A, and Bell 103
Operating Mode
Switched network
Two-wire full duplex
Private line
Two-wire or four-wire
Modulation
Above 14.4 kbps
Proprietary
14.4 kbps
128-level TCM/2400 Baud ±0.01%
12.0 kbps
64-level TCM/2400 Baud ±0.01%
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
A-1
Item
Specification
Modulation (cont.)
9600 bps
32-level TCM/2400 Baud ±0.01%
9600 bps
16-level QAM/2400 Baud ±0.01%
7200 bps
16-level TCM/2400 Baud ±0.01%
4800 bps
4-level QAM/2400 Baud ±0.01%
2400 bps
16-level QAM/600 Baud ±0.01%
1200 bps
4-level PSK/600 Baud ±0.01%
0-300 bps
FSK 0-300 Baud ±0.01%
Answer Tone
ITU-T V.32 bis, V.32, V.22 bis, V.22 and V.21
modes
2100 Hz ±3 Hz
ITU-T V.34
As specified by ITU-T
Bell 212A and 103 modes
2225 Hz ±3 H
Transmit Carrier
ITU-T V.34
As specified by ITU-T
ITU-T V.32 bis
As specified by ITU-T
ITU-T V.32
As specified by ITU-T
ITU-T V.22, V.22 bis/Bell 212A
Originate Mode
1200 Hz ±0.5 Hz
Answer Mode
2400 Hz ±1 Hz
ITU-T V.21
Originate Mode
Mark
Space
1180 Hz ±12 Hz 980 Hz ±12 Hz
Answer Mode
Mark
Space
1850 ±12 Hz
1650 ±12 Hz
Mark
Space
Bell 103
Originate Mode
1270 Hz ±12 Hz 1070 Hz ±12 Hz
Answer Mode
Mark
Space
2225 Hz ±12 Hz 2025 Hz ±12 Hz
Output Level
Permissive
-9 dBm maximum or per country requirements.
Programmable
-6 to -12 dBm (U.S. Only)
Note: Receiver performance in ITU-T V.34, V.32 bis, and V.32 modes may be
degraded when transmitting above -6 dBm.
A-2
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Item
Specification
Receive Carrier
ITU-T V.34
As specified by ITU-T
ITU-T V.32 bis
As specified by ITU-T
ITU-T V.32
As specified by ITU-T
Note: ITU-T V.34/V.32/V.32 bis, being echo canceling protocols, use signal quality
as criteria for maintaining connection. They also provide for self-training
detection to force disconnect.
ITU-T V.22 bis/Bell 212A
Originate Mode
2400 Hz ±7 Hz
Answer Mode
1200 Hz ±7 Hz
ITU-T V.21
Originate Mode
Answer Mode
Mark
Space
1850 ±12 Hz
1650 ±12 Hz
Mark
Space
1180 Hz ±12 Hz1650 Hz ±12 Hz
Bell 103
Originate Mode
Mark
Space
2225 Hz ±12 Hz2025 Hz ±12 Hz
Answer Mode
Mark
Space
1270 Hz ±12 Hz1070 Hz ±12 Hz
Receive Level
Switched Network
-6 to -43 dBm
Two-wire Private Line
-6 to -33 dBm
Four-wire Private Line
0 to -26 dBm
Carrier Detect (Level for ITU-T V.22 bis,
V.22, V.21, 212, 103) in Switched Network
Acquisition
-43 dBm
Hysteresis
2 dBm minimum
Release
-48 dBm
Note: ITU-T V.32/V.32 bis/V.34, being echo canceling protocols, use signal quality
as criteria for maintaining connection. They also provide for self-training detection
to force disconnect.
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
A-3
Item
Specification
DTE Interface
Standard
EIA/TIA-232-E (ITU-T V.24/V.28/ISO
2110)
Optional
EIA/TIA-530-A (ITU-T V.10/V.11/V.24/
ISO 2110 Amendment 1)
ITU-T V.35 (ITU-T V.24/V.28/V.35/ISO
2593)
ITU-T V.36 (requires a special
optional cable)
Line Requirements
Switched Network
Two-wire
Private Line
Two-wire or four-wire
Line Connection
Switched Network
8-position modular jack (US RJ45)
Phone
6-position modular jack (US RJ11)
Private Line
8-position modular jack (US RJ45)
Line Impedance
600 ohms or 900 ohms
Line Equalization
Automatic Adaptive
Connection Options
One second Line Break Holdover in
four-wire private line mode only.
Loss of Carrier in ITU-T V.22 bis and
lower.
Loop Current Disconnect.
Phone Types
500 (rotary dial), 2500 (DTMF dial),
and no phone
Dialing
Pulse and Tone
DTMF Output Level
USA
Per Part 68
International
per country requirements
Pulse Dial Ratio
USA
Make/Break: 39/61%
International
per country requirements
Ring Cadence
USA
On 2 seconds; Off 4 seconds
International
per country requirements
A-4
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Item
Specification
DC Loop Current
USA
20-80 milliamps
International
per country requirements
Call Progress Monitor
BUSY
CONNECT (rate) (see ITU-T V.42
options for delay)
CONNECT (see ITU-T V.42 options
for delay)
NO ANSWER
NO CARRIER
NO DIALTONE
OK (character abort)
RING
RINGING
UNOBTAINABLE NUMBER
Power Requirements
Voltage
99 to 129 V ac
Frequency
50 to 60 Hz
Dissipation
13.5 W ac maximum (line cord)
DC Voltage (Typical)
+5V
+5V ±5% at 1A
+12V
+12V ±5% at 0.2A
-12V
-12V ±5% at 0.2A
Dimensions (Printed circuit board with
DeskTop Enclosure)
Height
36 mm (1.4 in)
Width
188 mm (7.4 in)
Depth
279 mm (11 in)
Temperature
Operating
0 to 45×C (32× to 113×F)
Non-operating
-40 to 70×C (-40× to 158×F)
Humidity, operating
Up to 95 % humidity (noncondensing)
Altitude, operating
0 m to 3,047 m (0 to 10,000 ft)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
A-5
A-6
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Appendix B: Business Equipment
Interface (EIA/TIA-232-E,
ITU-T V.24/V.28/ISO 2110)
Circuit
232-E
V.24
Name
Pin No.
2
Direction
Function
Description
BA
103
SD
To DCE
Transmitted Data
The data signals originated by the DTE to be transmitted via a data
channel to remote data stations, or to be passed to the DCE for
maintenance test purposes under control of the DTE, are transferred on
this circuit to the DCE.
3
BB
104
RD
From DCE
Received Data
The data signals generated by the DCE in response to data channel line
signals received from a remote data station, or in response to the DTE
maintenance test signals, are transferred on this circuit to the DTE.
4
CA
105
RTS
To DCE
Request to Send
Signals on this circuit control the data transmit function of the DCE. The
On condition causes the DCE to assume the data channel transmit mode.
The Off condition causes the DCE to assume the data channel nontransmit mode when all data transferred on circuit 103 has been
transmitted.
5
CB
106
CTS
From DCE
Clear to Send
Signals on this circuit indicate whether the DCE is ready to operate. The
On condition indicates that the signal converter or similar equipment is
connected to the line and that the DCE is ready to exchange further
control signals with the DTE to initiate transfer of data. The Off condition
indicates that the DCE is not ready to operate.
6
CC
107
DSR
From DCE
Data Set Ready
Signals on this circuit indicate whether the DCE is ready to operate. The
On condition indicates that the signal converter or similar equipment is
connected to the line and that the DCE is ready to exchange further
control signals with the DTE to initiate transfer of data. The Off condition
indicates that the DCE is not ready to operate.
7
AB
102
SIG GND
Signal Ground
This pin is the signal ground reference for the V.24 interface circuits.
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
B-1
Circuit
232-E
V.24
Name
Function
Description
Pin No.
8
Direction
CF
109
CO/DCD
From DCE
Data Channel
Receive Line Signal
Detect
Signals on this circuit indicate whether the receive data channel line
signal is within appropriate limits, as specified in the relevant
recommendation for DCE. The On condition indicates that the received
signal is within appropriate limits. The Off condition indicates that the
received signal is not within the appropriate limits.
15
DB
114
SC
From DCE
Transmit Clock DCE
Source
Signals on this circuit are used to provide the data terminal equipment
with signal element timing information. The data terminal equipment shall
provide a data signal on the Transmit Data line in which the transitions
between signal elements nominally occur at the time of the Off-to-On
transitions of the signal on the DB circuit.
17
DD
115
RC
From DCE
Received Clock
Signals on this circuit are used to provide the data terminal equipment
with received signal element timing information. The On-to-Off transition
shall nominally indicate the center of each signal element on the BB
(Received Data) circuit.
18
LL
141
ALE
To DCE
Local Loopback
Signals on this circuit are used to provide test mode control of the local
loop 3.
20
CD
108/1
To DCE
Connect Data Set to
Line
Signals on this circuit control switching of the signal-conversion or other
similar equipment to or from the line. The On condition causes the DCE to
dial a stored phone number and connect the signal-conversion or similar
equipment to the line. The Off condition causes the DCE to remove the
signal-conversion or similar equipment from the line.
20
CD
108/2
DTR
To DCE
Data Terminal
Ready
Signals on this circuit control switching of the signal-conversion or similar
equipment to or from the line. The On condition, indicating that the DTE is
ready to operate, prepares the DCE to connect the signal conversion or
similar equipment to the line and maintains this connection after it has
been established by supplementary means. The DTE is permitted to
present the On condition on circuit 108.2 whenever it is ready to transmit
or receive data. The Off condition causes the DCE to remove the signalconversion or similar equipment from the line.
B-2
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Circuit
232-E
V.24
Name
Function
Description
Pin No.
21
Direction
2.5
140
RLE
To DCE
Remote Digital
loopback
The On condition in this circuit will initiate a Remote digital loopback test.
22
CE
125
RI
From DCE
Ring Indicator
The On condition of this circuit indicates that a ringing signal is being
received on the communication channel. The On signal shall appear
approximately coincident with the On segment of the ringing cycle (during
rings) on the communication channel.
23
CI
112
TC
From DCE
Speed Indicator
The On condition indicates that the modem is operating at the highest
speed within the selected handshake mode. The Off condition indicates
that a speed lower than the maximum was selected.
24
DA
113
TC
To DCE
Transmit Clock DTE
Source
Signals on this circuit are used to provide the transmitting signal
converter with signal element timing information. The On-to-Off transition
shall nominally indicate the center of each signal element on the BA
(Transmit Data) line.
25
TM
142
TME
From DCE
Test Mode Indicator
The On condition in this circuit indicates that a maintenance condition in
the DCE, precluding reception or transmission of data signals from or to a
remote DTE. The Off condition indicates that the DCE is not in
maintenance test condition.
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
B-3
B-4
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Appendix C: Business Equipment
Interface (EIA/TIA-530-A,
ITU-T V.10/V.11/V.24/ISO 2110)
Circuit
Name
Pin No.
530
Direction
Function
V.11
Description
2
BA-A
103-A
SD
To DCE
Transmitted Data
The data signals originated by the DTE to be transmitted via a data
channel to remote data stations, or to be passed to the DCE for
maintenance test purposes under control of the DTE, are transferred on
this circuit to the DCE.
3
BB-A
104-A
RD
From DCE
Received Data
The data signals generated by the DCE in response to data channel line
signals received from a remote data station, or in response to the DTE
maintenance test signals, are transferred on this circuit to the DTE.
4
CA-A
105-A
RTS
To DCE
Request to Send
Signals on this circuit control the data transmit function of the DCE. The
On condition causes the DCE to assume the data channel transmit mode.
The Off condition causes the DCE to assume the data channel nontransmit mode when all data transferred on circuit 103 has been
transmitted.
5
CB-A
106-A
CTS
From DCE
Clear to Send
Signals on this circuit indicate whether the DCE is ready to operate. The
On condition indicates that the signal converter or similar equipment is
connected to the line and that the DCE is ready to exchange further
control signals with the DTE to initiate transfer of data. The Off condition
indicates that the DCE is not ready to operate.
6
CC
107
DSR
From DCE
Data Set Ready
Signals on this circuit indicate whether the DCE is ready to operate. The
On condition indicates that the signal converter or similar equipment is
connected to the line and that the DCE is ready to exchange further
control signals with the DTE to initiate transfer of data. The Off condition
indicates that the DCE is not ready to operate.
7
AB
102-A
SIG GND
Signal Ground
This pin is the signal ground reference for the V.11 interface circuits.
(Sheet 1 of 4)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
C-1
Circuit
Name
Pin No.
530
Direction
Function
V.11
Description
8
CF-A
109-A
CO/DCD
From DCE
Data Channel Receive
Line Signal Detect
Signals on this circuit indicate whether the receive data channel line signal
is within appropriate limits, as specified in the relevant recommendation for
DCE. The On condition indicates that the received signal is within
appropriate limits. The Off condition indicates that the received signal is
not within the appropriate limits.
9
DD-B
10
CF-B
115-B
RC
From DCE
Received Clock
From DCE
Data Channel Receive
Line Signal Detect
To DCE
Transmit Clock DTE
Source
From DCE
Transmit Clock DCE
Source
From DCE
Clear to Send
To DCE
Transmitted Data
From DCE
Transmit Clock DCE
Source
See pin 17, circuit DD-A.
109-B
CO/DCD
See pin 8, circuit CF-A.
11
DA-B
12
DB-B
113-B
TC
See pin 24, circuit DA-A.
114-B
SC
See pin 15, circuit DB-A.
13
CB-B
106-B
CTS
See pin 5, circuit CB-A.
14
BA-B
103-B
SD
See pin 2, circuit BA-A.
15
DB-A
114-A
SC
Signals on this circuit are used to provide the DTE with signal element
timing information. The data terminal equipment shall provide a data
signal on the Transmit Data line in which the transitions between signal
elements nominally occur at the time of the Off-to-On transitions of the
signal on the DB circuit.
16
BB-B
17
DD-A
104-B
RD
From DCE
Received Data
From DCE
Received Clock
See pin 3, circuit BB-A.
115-A
RC
Signals on this circuit are used to provide the DTE with received signal
element timing information. The On-to-Off transition shall nominally
indicate the center of each signal element on the BB (Received Data)
circuit.
(Sheet 2 of 4)
C-2
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Circuit
Name
Pin No.
530
Direction
Function
V.11
Description
18
LL
141
ALE
To DCE
Local Loopback
Signals on this circuit are used to provide test mode control of the local
loop 3.
19
CA-B
20
CD
105-B
RTS
To DCE
Request to Send
To DCE
Connect Data Set to
Line
See pin 4, circuit CA-A.
108.1
Signals on this circuit control switching of the signal-conversion or other
similar equipment to or from the line. The On condition causes the DCE to
dial a stored phone number and connect the signal-conversion or similar
equipment to the line. The Off condition causes the DCE to remove the
signal-conversion or similar equipment from the line.
20
CD
108.2
DTR
To DCE
Data Terminal Ready
Signals on this circuit control switching of the signal-conversion or similar
equipment to or from the line. The On condition, indicating that the DTE is
ready to operate, prepares the DCE to connect the signal conversion or
similar equipment to the line and maintains this connection after it has
been established by supplementary means. The DTE is permitted to
present the On condition on circuit 108.2 whenever it is ready to transmit
or receive data. The Off condition causes the DCE to remove the signalconversion or similar equipment from the line.
21
RL
140
RLE
To DCE
Remote Digital
loopback
The On condition in this circuit will initiate a Remote digital loopback test.
22
CE
125
RI
From DCE
Ring Indicator
The On condition of this circuit indicates that a ringing signal is being
received on the communication channel. The On signal shall appear
approximately coincident with the On segment of the ringing cycle (during
rings) on the communication channel.
23
CI
112
TC
From DCE
Speed Indicator
The On condition indicates that the modem is operating at the highest
speed within the selected handshake mode. The Off condition indicates
that a speed lower than the maximum was selected.
(Sheet 3 of 4)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
C-3
Circuit
Name
Pin No.
530
Direction
Function
V.11
Description
24
DA-A
113-A
TC
To DCE
Transmit Clock DTE
Source
Signals on this circuit are used to provide the transmitting signal converter
with signal element timing information. The On-to-Off transition shall
nominally indicate the center of each signal element on the BA (Transmit
Data) line.
25
TM
142
TME
From DCE
Test Mode Indicator
The On condition in this circuit indicates that a maintenance condition in
the DCE, precluding reception or transmission of data signals from or to a
remote DTE. The Off condition indicates that the DCE is not in
maintenance test condition.
(Sheet 4 of 4)
C-4
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Appendix D: Business Equipment
Interface
(ITU-T V.35/V.24/V.28/ISO 2593)
Pin No.
V.35
B
Circuit
Name
DB25
7
Direction
Function
Description
102
SIG GND
Signal ground
Establishes a common ground reference for all interface circuits
except protective ground.
C
4
105
RTS
To DCE
Request to send
Signals on this circuit control the data transmit function of the DCE.
The On condition causes the DCE to assume the data channel
transmit mode. The Off condition causes the DCE to assume the
data channel non-transmit mode when all data transferred on circuit
103 has been transmitted.
D
5
106
CTS
From DCE
Clear to send
Signals on this circuit indicate whether the DCE is ready to transfer
data. The On condition indicates that the signal converter or similar
equipment is connected to the line and that the DCE is ready to
initiate transfer of data. The Off condition indicates that the DCE is
not ready to transfer data.
E
6
107
DSR
From DCE
Data set ready
Signals on this circuit indicate whether the DCE is ready to operate.
The On condition indicates that the signal converter or similar
equipment is connected to the line and that the DCE is ready to
exchange further control signals with the DTE to initiate transfer of
data. The Off condition indicates that the DCE is not ready to
operate.
F
8
109
CO/DCD
From DCE
Receive line signal detect
Signals on this circuit indicate whether the receive data channel line
signal is within appropriate limits, as specified in the relevant
recommendation for DCE. The On condition indicates that the
received signal is within appropriate limits. The Off condition
indicates that the received signal is not within the appropriate limits.
054R207-000
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V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
D-1
Pin No.
V.35
H
Circuit
Name
DB25
20
Direction
Function
Description
108.1
To DCE
Connect Data Set to Line
Signals on this circuit control switching of the signal-conversion or
other similar equipment to or from the line. The On condition causes
the DCE to dial a stored phone number and connect the signalconversion or similar equipment to the line. The On condition
following Ring Indicator causes the DCE to perform automatic
answer. The Off condition causes the DCE to remove the signalconversion or similar equipment from the line.
H
20
108.2
DTR
To DCE
Data terminal ready
Signals on this circuit control switching of the signal-conversion or
similar equipment to or from the line. The On condition, indicating
that the DTE is ready to operate, prepares the DCE to connect the
signal conversion or similar equipment to the line and maintains this
connection after it has been established by supplementary means.
The DTE is permitted to present the On condition on circuit 108.2
whenever it is ready to transmit or receive data. The Off condition
causes the DCE to remove the signal-conversion or similar
equipment from the line.
NN
25
142
TME
From DCE
Test mode
The On condition in this circuit indicates a test mode in the DCE,
precluding reception or transmission of data signals from or to a
remote DTE. The Off condition indicates the DCE is not in test mode.
L
18
P
2
141
ALE
To DCE
Analog Loopback enable
Signals on this circuit are used to control Analog Loopback test.
103
SD-A
To DCE
Transmitted data
Data signals originated by the DTE - to be transmitted to a remote
data station via a data channel, or to be passed to the DCE for
maintenance test purposes under control of the DTE - are
transferred to the DCE on this circuit.
R
3
104
RD-A
From DCE
Received data
Data signals generated by the DCE - in response to data channel
line signals received from a remote modem, or in response to DTE
maintenance test signals - are transferred to the DTE on this circuit.
S
14
103
SD-B
To DCE
Transmitted data
From DCE
Received data
See pin P/2, SD-A.
T
16
104
RD-B
See pin R/3, RD-A.
D-2
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Pin No.
V.35
U
Circuit
Name
DB25
24
Direction
Function
Description
113
TT-A
To DCE
Terminal timing
Signals on this circuit are used to provide the transmitting signal
converter with signal element timing information. The On-to-Off
transition shall nominally indicate the center of each signal element
on the Transmit Data line.
V
17
115
RT-A
From DCE
Receive timing
Signals on this circuit are used to provide the data terminal
equipment with received signal element timing information. The Onto-Off transition shall nominally indicate the center of each signal
element on the Received Data circuit.
W
11
X
9
Y
15
113
TT-B
To DCE
Terminal timing
From DCE
Receive timing
From DCE
Transmit timing
See pin U/24, TT-A.
115
RT-B
See pin V/17, RT-A.
114
ST-A
Signals on this circuit are used to provide the data terminal
equipment with signal element timing information. The data terminal
equipment shall provide a data signal on the Transmit Data line in
which the transitions between signal elements nominally occur at the
time of the Off-to-On transitions of the signal on this circuit.
AA/a
12
N
21
J
22
114
ST-B
From DCE
Transmit timing
To DCE
ReDigital Loopback enable
See pin Y/15, ST-A.
140
RLE
Transfers signal from DTE to control RDL test mode.
125
RI
From DCE
Ring Indicator
The On condition of this circuit indicates that a ringing signal is being
received on the communication channel. The On signal shall appear
approximately coincident with the On segment of the ringing cycle
(during rings) on the communication channel.
-
23
112
CI
From DCE
Speed Indicator
The On condition indicates that the modem is operating at the
highest speed within the selected handshake mode. The Off
condition indicates that a speed lower than the maximum was
selected.
054R207-000
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V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
D-3
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
D-4
Appendix E: ASCII/EBCDIC
Character Sets And
Hexadecimal/Binary Conversions
ASCII Character
EBCDIC
Character
Decimal
Hexadecimal
Binary
NUL
NUL
0
00
00000000
CTRL A (SOH)
SOH
1
01
00000001
CTRL B (STX)
STX
2
02
00000010
CTRL C (ETX)
ETX
3
03
00000011
CTRL D (EOT)
PF
4
04
00000100
CTRL E (ENO)
HT
5
05
00000101
CTRL F (ACK)
LC
6
06
00000110
CTRL G (BEL)
DEL
CTRL H (BS)
7
07
00000111
8
08
00001000
CTRL I (HT)
RLF
9
09
00001001
CTRL J (LF)
SMM
10
0A
00001010
CTRL K (VT)
VT
11
0B
00001011
CTRL L (FF)
FF
12
0C
00001100
CTRL M (CR)
CR
13
0D
00001101
CTRL N (SO)
SC
14
0E
00001110
CTRL O (SI)
SI
15
0F
00001111
CTRL P (DLE)
DLE
16
10
00010000
CTRL Q (XON)
DC1
17
11
00010001
CTRL R (DC2)
DC2
18
12
00010010
CTRL S (XOFF)
DC3
19
13
00010011
CTRL T (DC4)
RES
20
14
00010100
CTRL U (NAK)
NL
21
15
00010101
CTRL V (SYN)
BS
22
16
00010110
CTRL W (ETB)
IL
23
17
00010111
CTRL X (CAN)
CAN
24
18
00011000
CTRL Y (EM)
EM
25
19
00011001
(Sheet 1 of 5)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
E-1
ASCII Character
EBCDIC
Character
Decimal
Hexadecimal
Binary
CTRL Z (SUB)
CC
26
1A
00011010
27
1B
00011011
FS
ITS
28
1C
00011100
GS
IGS
29
1D
00011101
RS
IRS
30
1E
00011110
US
IUS
31
1F
00011111
SP
DS
32
20
00100000
!
SOS
33
21
00100001
"
FS
34
22
00100010
ESC
#
35
23
00100011
BYP
36
24
00100100
%
LF
37
25
00100101
&
EOB
38
26
00100110
'
ESC
$
(
)
*
39
27
00100111
40
28
00101000
41
29
00101001
3M
42
2A
00101010
43
2B
00101011
'
44
2C
00101100
+
-
ENR
45
2D
00101101
.
ACK
46
2E
00101110
/
BEL
0
1
2
SYN
3
47
2F
00101111
48
30
00110000
49
31
00110001
50
32
00110010
51
33
00110011
PN
52
34
00110100
5
RS
53
35
00110101
6
UC
54
36
00110110
7
EOT
4
55
37
00110111
8
56
38
00111000
9
57
39
00111001
:
58
3A
00111010
(Sheet 2 of 5)
E-2
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
ASCII Character
EBCDIC
Character
;
Decimal
Hexadecimal
Binary
59
3B
00111011
<
DC4
60
3C
00111100
=
NAK
61
3D
00111101
62
3E
00111110
?
SUB
63
3F
00111111
@
SP
>
64
40
01000000
A
65
41
01000001
B
66
42
01000010
C
67
43
01000011
D
68
44
01000100
E
69
45
01000101
F
70
46
01000110
G
71
47
01000111
H
72
48
01001000
I
73
49
01001001
J
¢
74
4A
01001010
K
.
75
4B
01001011
L
<
76
4C
01001100
M
(
77
4D
01001101
N
+
78
4E
01001110
O
|
79
4F
01001111
P
&
80
50
01010000
Q
81
51
01010001
R
82
52
01010010
S
83
53
01010011
T
84
54
01010100
U
85
55
01010101
V
86
56
01010110
W
87
57
01010111
X
88
58
01011000
Y
89
59
01011001
Z
!
90
5A
01011010
[
$
91
5B
01011011
(Sheet 3 of 5)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
E-3
ASCII Character
EBCDIC
Character
Decimal
Hexadecimal
Binary
\
#
92
5C
01011100
]
)
93
5D
01011101
^
;
94
5E
01011110
-
95
5F
01011111
`
-
96
60
01100000
a
/
97
61
01100001
98
62
01100010
b
c
99
63
01100011
d
100
64
01100100
e
101
65
01100101
f
102
66
01100110
g
103
67
01100111
h
104
68
01101000
i
/
105
69
01101001
j
|
106
6A
01101010
k
'
107
6B
01101011
l
%
108
6C
01101100
m
109
6D
01101101
n
110
6E
01101110
111
6F
01101111
112
70
01110000
o
?
p
q
113
71
01110001
r
114
72
01110010
s
115
73
01110011
t
116
74
01110100
u
117
75
01110101
v
118
76
01110110
w
119
77
01110111
x
120
78
01111000
y
121
79
01111001
:
122
7A
01111010
{
#
123
7B
01111011
|
@
124
7C
01111100
z
(Sheet 4 of 5)
E-4
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
ASCII Character
EBCDIC
Character
Decimal
Hexadecimal
Binary
}
'
125
7D
01111101
~
=
126
7E
01111110
DEL
"
127
7F
01111111
(Sheet 5 of 5)
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
E-5
EBCDIC
Char.
Decimal
128
80
10000000
160
A0
10100000
a
129
81
10000001
161
A1
10100001
b
130
82
10000010
s
162
A2
10100010
c
131
83
10000011
t
163
A3
10100011
d
132
84
10000100
u
164
A4
10100100
e
133
85
10000101
v
165
A5
10100101
g
135
87
10000111
x
167
A7
10100111
h
136
88
10001000
y
168
A8
10101000
i
137
89
10001001
z
169
A9
10101001
138
8A
10001010
170
AA
10101010
139
8B
10001011
171
AB
10101011
140
8C
10001100
172
AC
10101100
141
8D
10001101
173
AD
10101101
142
8E
10001110
174
AE
10101110
143
8F
10001111
175
AF
10101111
144
90
10010000
176
B0
10110000
E-6
Hex
Binary
EBCDIC
Char.
Decimal
Hex
Binary
j
145
91
10010001
177
B1
10110001
k
146
92
10010010
178
B2
10110010
l
147
93
10010011
179
B3
10110011
m
148
94
10010100
180
B4
10110100
n
149
95
10010101
181
B5
10110101
o
150
96
10010110
182
B6
10110110
p
151
97
10010111
183
B7
10110111
q
152
98
10011000
184
B8
10111000
r
153
99
10011001
185
B9
10111001
154
9A
10011010
186
BA
10111010
155
9B
10011011
187
BB
10111011
156
9C
10011100
188
BC
10111100
157
9D
10011101
189
BD
10111101
158
9E
10011110
190
BE
10111110
159
9F
10011111
191
BF
10111111
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
EBCDIC
Char.
Decimal
Hex
Binary
EBCDIC
Char.
'
{
192
C0
11000000
A
193
C1
11000001
Decimal
Hex
Binary
224
E0
11100000
225
E1
11100001
B
194
C2
11000010
S
226
E2
11100010
C
195
C3
11000011
T
227
E3
11100011
D
196
C4
11000100
U
228
E4
11100100
E
197
C5
11000101
V
229
E5
11100101
F
198
C6
11000110
W
230
E6
11100110
G
199
C7
11000111
X
231
E7
11100111
H
200
C8
11001000
Y
232
E8
11101000
I
201
C9
11001001
Z
233
E9
11101001
202
CA
11001010
234
EA
11101010
203
CB
11001011
235
EB
11101011
204
CC
11001100
236
EC
11101100
205
CD
11001101
237
ED
11101101
206
CE
11001110
238
EE
11101110
207
CF
11001111
239
EF
11101111
}
208
D0
11010000
0
240
F0
11110000
J
209
D1
11010001
1
241
F1
11110001
K
210
D2
11010010
2
242
F2
11110010
L
211
D3
11010011
3
243
F3
11110011
M
212
D4
11010100
4
244
F4
11110100
N
213
D5
11010101
5
245
F5
11110101
O
214
D6
11010110
6
246
F6
11110110
P
215
D7
11010111
7
247
F7
11110111
Q
216
D8
11011000
8
248
F8
11111000
R
217
D9
11011001
9
249
F9
11111001
218
DA
11011010
250
FA
11111010
219
DB
11011011
251
FB
11111011
220
DC
11011100
252
FC
11111100
221
DD
11011101
253
FD
11111101
222
DE
11011110
254
FE
11111110
223
DF
11011111
255
FF
11111111
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
E-7
ASCII CHARACTER PARITY SELECTION
BITS
E-8
START
DATA
PARITY
STOP
1
8
None
1
1
7
Even
1
1
7
Odd
1
1
7
Mark
1
1
7
Space
1
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Index
Numerics
108 Modes 5-1
108.1 Mode 5-2
108.1 Mode Operating Procedures 5-14
108.2 Call Establishment Procedure 5-13
108.2 Mode 5-1
108.2 Mode Operating Procedures 5-11
A
Analog Loopback 6-3
Analog Loopback With Self-test 6-4
Answer call command (A) 4-25
Asynchronous Dialing with Synchronous Transmission 3-32
Asynchronous Operation 3-28
AT Command Mode 3-23
AT Command Reference 4-24
$ 4-24
%$ 4-24
%An 4-25
%Bn 4-26
%Cn 4-27
%Dn 4-29
%En 4-29
%Fn 4-33
%Fn=x 4-33
%Kn 4-36
%On 4-39
%Pn=nnn 4-40
%Qn 4-40
%Rn 4-42
%Sn 4-49
%Vn 4-52
%Zn 4-58
&$ 4-24
&An 4-25
&Bn 4-26
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
IX-1
Index
&Cn 4-26
&Dn 4-29
&En 4-29
&Fn 4-30
&Gn 4-34
&Hn 4-35
&In 4-36
&Ln 4-37
&Mn 4-38
&Pn 4-39
&Rn 4-41
&Sn 4-48
&Tn 4-49
&Un 4-51
&V 4-52
&Wn 4-56
&Xn 4-56
&Yn 4-57
&Zn=nnn 4-57
*$ 4-24
*Pn 4-40
*Rn 4-43
*Wn 4-56
*Xn 4-57
:$ 4-24
:Pn 4-40
\$ 4-24
\An 4-25
\Bn 4-26
\Cn 4-27
\Kn 4-37
\Mn 4-38
\Pn 4-40
\Qn 4-41
\Tn 4-50
\Vn 4-52
A 4-25
A/ 4-26
An 4-25
Dn 4-28
En 4-29
Gn 4-34
Hn 4-35
IX-2
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Index
In 4-36
Ln 4-37
Mn 4-37
N? 4-38
P 4-39
Qn 4-40
S$ 4-25, 4-43
Sn 4-43
S-Register 4-45
T 4-49
Vn 4-52
Xn 4-56
Yn 4-57
Zn 4-57
AT Command Set Operation 4-1
AT Commands 3-22
AT Commands Listed by Function 4-6
Automatic DTE Speed 3-25
C
Call Control 3-15
Answering - Automatic 3-18
Answering - Manual 3-18
Automatic Initiation in Response to DTR 3-16
Disconnecting a Call 3-19
Manual Initiation 3-15
Manual Initiation with a Stored Number 3-16
Clock Selection 3-35
Command Buffer 3-25
Command Mode 3-22
Command Set Summaries
Extended AT 4-21
Extended AT% 4-18
Extended AT& 4-15
Extended AT* 4-23
Extended AT: 4-23
Command Syntax 3-24
Commanding The Modem 4-1, 5-2
Communication Operation 3-22
Configuration Profiles 3-23
Cover Removal And Replacement 2-5
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
IX-3
Index
D
Data Mode 3-22, 3-27
Description 1-2
Digital Loopback 6-5
Direct V.14 Asynchronous Mode 3-30
DTE Cables 1-3
DTE Interface Card 2-6
E
End-to-End Self-Test 6-9
Error Correcting Modes 3-29
F
Fax 1-3
Features 1-1
Flow Control 3-30
Hardware 3-31
Software 3-31
Front Panel, Using 3-1
H
High Data Rates, Special Considerations 2-3
I
Installation 2-1
Interface Connections 5-16
ITU-T V.25 bis Command Set Operating Procedures 5-11
K
Keypad, Using 3-1
M
Modem Equipment 1-2
Modem Test Modes 5-18
N
Non-Error Correcting Modes 3-29
IX-4
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
054R207-000
Issue 11
Index
O
On-line Password Callback Extensions 3-21
Operating Procedures 5-2
Option Jumpers 2-5
Option Plug-in Cards 2-6
P
Parity Detection 3-25
Passwords 3-19
Private Line Operation
Auto Dial Restoral 3-39
Automatic and Manual Handshaking 3-38
Four-wire 3-37
Other Configuration 3-37
Transmit Level 3-38
Two-wire 3-37
PRS DR 5-6
PRS HM 5-8
R
Remote Configuration Using AT Commands 3-26
Remote Digital Loopback 6-6
Remote Digital Loopback With Self-Test 6-7
S
Security Callback 3-20
Software Selection 1-3
Switched Network Operation 3-36
Synchronous Compression Mode 3-34
Synchronous Format Selection 5-17
Synchronous Operating Modes 3-32
Direct Dialing 3-33
Normal 3-33
V.13 3-33
Synchronous Operation 3-32
T
Telephone Lines 3-36
Testing The Modem 3-40
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
IX-5
Index
U
Unpacking Your Modem 2-1
V
V.13 Mode 3-30
V.25 bis 108.2 Mode Interface Specifications 5-16
V.25 bis Configuration Commands 5-5
V.42 (LAPM) Reliable Mode Error Correction 3-29
Verifying Your Connections 2-4
VF Card 2-6
W
Wire Mode 3-30
054R207-000
Issue 11
V.F 28.8/33.6 Modem DeskTop Platform
Installation and Operation
IX-6
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