Simpletech 28.8 Communicator User Manual

28.8 Communicator

V.34 Data/Fax Modem

Plug n’ Play PC Card

User Guide

Document Part Number 61000-00228-000

i

1-800-367-7330

3001 Daimler Street, Santa Ana, California 92705

[phone] [phone] fax

ii

28.8 Communicator

V.34 Data/Fax Modem

Plug n’ Play PC Card

User Guide

iii

Limited Warranty

Simple Technology Incorporated guarantees its products to be of
the highest quality, and to be free of defects in material, design
and workmanship. STI will repair or replace this product,
without charge for either parts or labor, if it is returned due to
defects in material, design, and/or workmanship only. This
guarantee applies only if the product has not been misused,
modified, repaired, neglected, improperly installed, abused, or
otherwise damaged as has not been mentioned above.

Copyright

© Copyright 1995 Simple Technology Inc., all rights reserved.
No part of this publication may be reproduced, transmitted,
transcribed, stored in a retrieval system, or translated into any
language or computer language, in any form, by any means,
electronic, mechanical, magnetic, optical, chemical, manual or
otherwise, without expressed written consent of STI.

Disclaimer

Specifications subject to change without notice. Simple Technology
Inc. makes no representations or warranties with respect to the
contents hereof and specifically disclaims any implied warranties
of merchantability or fitness for any particular purpose. Further,
STI reserves the right to revise this publication and to make
changes from time to time in the content hereof without obligation
of STI to notify any person of such revision.

Products and brand names are trademarks and/or registered
trademarks of their respective companies.

iv

Contents

1 Introduction ..........................................................1

Using the Guides ...................................................2

Installation Requirements.......................................3

Unpacking the Card ...............................................4

Technical Support..................................................4

2 Describing the Kit ..................................................5

The Hardware........................................................5

The Software .........................................................7

Specifications ........................................................7

3 Installing the Card ..................................................9

Checking for Card and Socket Services..................9

Attaching the Card ..............................................10

Installing the Communication Software................10

Configuring the Communication Software ......11

4 Using the Card .....................................................13

Inserting or Removing Your Card..........................13

About Call Waiting...............................................13

Connecting to Cell Phones...................................14

Protecting the Card .............................................14

v

5 Using AT Commands.............................................15

Some Notes About AT Commands.......................17

Configuring the Modem .......................................18

Sample Configuration 1 ..................................18

Sample Configuration 2 ..................................19

Sample Configuration 3 ..................................20

AT Commands......................................................21

AT& Commands..............................................27

AT% Commands .............................................35

AT\ Commands ...............................................36

AT) Commands...............................................40

AT@ Commands..............................................40

AT* Commands...............................................41

AT: Commands................................................41

AT- Commands ...............................................41

6 Fax and Voice Commands ....................................43

7 Result Codes and Messages .................................45

8 S-Registers ...........................................................49

Example: Writing to an S-Register.........................53

Bit-Mapped Options S-Registers ..........................53

Example: Setting an S-Register.............................54

Example: Interpreting an S-Register .....................55

vi

FCC and DOC Compliance

The following statements are provided in accordance with
Federal Communications Commission (FCC) and Canadian
Department of Communications (DOC). Please read these
statements carefully before installing or operating your modem.

FCC Part 68 Requirements

This equipment complies with Part 68 of the FCC Rules. On
the bottom of this equipment is a label that contains, among
other information, the FCC Registration Number and Ringer
Equivalence Number (REN) for this equipment. If requested,
this information must be given to the telephone company.

The REN is used to determine the maximum number of devices
connected to your telephone line that will ring in response to an
incoming call. In most, but not all, areas, the total REN of
devices connected to a line should not exceed five (5.0). To find
out the total permitted in your area, contact your local telephone
company.

If your telephone equipment causes harm to the telephone network,
the telephone company may discontinue your service temporarily.
If possible, the company will notify you in advance. But if advance
notice isn’t practical, you will be notified as soon as possible. You
will also be informed of your right to file a complaint with the FCC.
If your equipment is the cause of the problem, you will be given the
opportunity to correct the problem.

Your telephone company can make changes in its facilities,
equipment, operations, or procedures that could affect the
operation of your equipment. If so, you will be notified in
advance so you can make the changes needed to maintain
uninterrupted service.

vii

If you experience trouble with this telephone equipment,
please contact Simple Technology at 1-800-367-7330 for
information on obtaining service or repairs. The telephone
company may ask that you disconnect this equipment from
the network until the problem has been corrected or until you
are sure that the equipment is not malfunctioning.

This equipment contains no user serviceable parts.
This equipment may not be used on public coin service or party

lines.

FCC Part 15 Requirements

This equipment has been tested and found to comply with the limits
for a class B digital device, pursuant to part 15 of the FCC Rules.
These limits are designed to provide reasonable pr otection against
harmful interference in a residential installation. This equipment
generates, uses and can radiate radio frequency energy and if not
installed and used in accordance with the instructions, may cause
harmful interference to radio communications. However , there is no
guarantee that interference will not occur in a particular installation.
If this equipment does cause harmful interference to radio or
television reception, which can be determined by turning the
equipment off and on, the user is encouraged to try to correct the
interference by one or more of the following measur es:

• Reorient or relocate the receiving antenna.

• Increase the separation between the equipment and
receiver.

• Connect the equipment into an outlet on a circuit different
from that to which the receiver is connected.

• Consult the dealer or an experienced radio/TV technician
for help.

The user is cautioned that changes and modifications made to
this equipment without the approval of the manufacturer could
void the user’s authority to operate this equipment. There are no
user-serviceable parts in this equipment. The unit must be
returned to the manufacturer for any repairs.

viii

DOC Certification Label

The Canadian Department of Communications (DOC) label
identifies certified equipment. This certification means that the
equipment meets certain telecommunications network protective,
operational, and safety requirements. The Department does not
guarantee the equipment will operate to the user’s satisfaction.

Before installing this equipment, users should ensure that it
is permissible to be connected to the facilities of the local
telecommunications company. The equipment must also be
installed using an acceptable method of connection. In some
cases, the company’s inside wiring associated with a single
line individual service may be extended by means of a
certified connector assembly (telephone extension cord). The
customer should be aware that compliance with the above
conditions may not prevent degradation of service in some
situations.

Repairs to certified equipment should be made by an authorized
Canadian maintenance facility designated by the supplier. Any
repairs or alterations made by the user to this equipment, or
equipment malfunctions, may give the telecommunications
company cause to request the user to disconnect the equipment.

Users should ensure for their own protection that the electrical
ground connections of the power utility, telephone lines, and
internal metallic water pipe system, if present, are connected
together. This precaution may be particularly important in rural
areas.

CAUTION: Do not attempt to make electrical ground

connections yourself; contact the
appropriate electric inspection authority
or an electrician.

ix

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

Warranty and Repair Service in Canada

Target Electronics
1111 Flint Rd. #28
Downview ONT M3J 3C7
[phone]

DOC ICES-003 Compliance

This digital apparatus does not exceed the class B limits for radio
noise emissions from digital apparatus as set out in the interfer­ence-causing equipment entitled “Digital Apparatus,” ICES-003
of the Department of Communications.

Cet appareil numerique respecte les limites de bruits radio­electriques applicables aux appareils numeriques de Classe B
prescrites dans la norme sur le materiell brouilleur “Appareils
Numeriques,” NMB-003 edictee par le ministre des Communica­tions.

Etiquette D’Homologation du Ministere
des Communications du Canada

AVIS : L’etiquette du ministere des Communications du Canada
identifie le materiel homologue. Cette etiquette certifie que le
materiel est conforme a certaines normes de protection,
d’exploitation et de securite des reseaux de telecommunications.
Le ministere n’assure toutefois pas que le materiel fonctionnera a
la satisfaction de l’utilisateur.

x

Avant d’installer ce materiel, l’utilisateur doit s’assurer qu’il est
permis de le raccorder aux installations de l’entreprise locale de
telecommunications. Le materiel doit egalement etre installe en
suivant une methode acceptee de raccordement. L’abonne ne
doit pas oublier qu’il est possible que la conformite aux condi­tions enoncees ci-dessus n’empechent pas la degradation du
service dans certaines situations.

Les reparations de materiel homologue doivent etre effectuees
par un centre d’entretien canadien autorise designe par le
fournisseur. La compagnie de telecommunications peut de­mander a l’utilisateur de debrancher un appareil a la suite de
reparations ou de modifications effectuees par l’utilisateur ou a
cause d’un mauvais fonctionnement.

Pour sa propre protection, l’utilisateur doit s’assurer que tous les
fils de mise a la terre de la source d’energie electrique, des lignes
telephoniques et des canalisations d’eau metalliques, s’il y en a,
sont raccordes ensemble. Cette precaution est particulierement
importante dans les regions rurales.

AVERTISSEMENT : l’utilisateur ne doit pas tenter de faire ces
raccordements lui-meme, il doit avoir recours a un service
d’inspection des installations electriques ou a un electricien,
selon le cas.

AVIS : L’INDICE DE CHARGE (IC) assigne a chaque dispositif
terminal indique, pour eviter toute surcharge, le pourcentage de
la charge totale qui peut etre raccorde a un circuit telephonique
boucle utilise par ce dispositif.

L’extremite du circuit boucle peut consister en n’importe quelle
combinaison de dispositifs pourvu que la somme des INDICES
DE CHARGE de l’ensemble des dispositifs ne depasse pas 100.

xi

Notes:

xii

1. Introduction

This is a User Guide for the 28.8 Communicator PC Card
manufactured by Simple Technology. The 28.8 Communicator
is a modem PC Card that features 28.8 Kbps data transfer,

14.4 Kbs fax, cellular-ready, and voice capabilities.
The card allows you to send and receive data and fax. Also, the

card is cellular ready. With an optional cell phone cable, you can
use the data, fax, and voice features of the card with a cellular
phone. The voice capabilities of the card allow you to use your
computer as an answering machine.

The PC Card works with PCMCIA Release 2.1 Type II specifica­tions, standard on most laptop and notebook computers.

The PCMCIA standard allows for easy hardware installation—
just plug the card into your computer card socket. The card
features Plug n’ Play, allowing you to install the card with your
computer power turned on.

The credit-card size and easy installation of the card makes it
ideal for carrying the modem between computers. This allows
you to buy one modem for use with several computers.

Also included with the card is communication software for
Windows and its User Guide. The communication software
provides a software user interface for the modem.

1

Using the Guides

Read the rest of this chapter for information about the Installation
Requirements, Unpacking the Card, and Technical Support. Then,

read the following chapters as follows:

1. Refer to Chapter 2 for an overview description of the kit
components.

2. Refer to Chapter 3 for instructions on installing the card.

3. Refer to Chapter 4 for further information on using the
card.

4. Refer to the guide that is provided with the communica­tion software for instructions on installation and start-up
of the communication software.

5. Refer to the Chapters 5 to 8 for technical information on
the modem AT commands and S-Registers.

6. Refer to the Connecting the STI Modem to Cell Phones flyer
for information on obtaining a cable for your cell phone.

2

Installation Requirements

The following are the minimum requirements for installing the
card:

• A computer with the following features:

- An available PC Card Type II socket

- 80386 or higher microprocessor

- 2 MB of RAM

- An internal hard drive

- A 3.5-inch floppy drive

• The following operating systems:

- MS-DOS v5.0 or later, and Windows v3.1

- Card and Socket Services compatible to PCMCIA
Release 2.1 specifications

• An available phone line

• A handset (optional)

NOTE: There is no industry standard for the signal

polarity of handsets; therefore, the modem does
not work with all handsets.

3

Unpacking the Card

The following items are included with your kit:

• 28.8 Communicator

• Line Access Cable

• User Guide
(this document)

• Simple Installation Instructions

• Connecting the STI Modem to Cell Phones flyer
(P/N 61000-00062-xxx)

• Communications Software and User Guide.

If any item is missing or damaged, contact your dealer immedi­ately.

Technical Support

If you experience any difficulties with the installation of the card,
call Technical Support at the following telephone numbers:

• [phone]

• 1-800-367-7330

4

2. Describing the Kit

Use the descriptions and illustrations in this chapter to become
familiar with your kit.

The Hardware

Refer to the figures and the descriptions below and on the next
page to become familiar with the hardware:

• The 28.8 Communicator (see Figure 2-1). The Type II PC Car d
contains a connector for a PC Card socket, and a connector
for the Line Access Cable. The card is encased in metal,
allowing for safe handling. With Card and Socket Services
provided with your computer, the card features Plug n’ Play
capability, i.e., the ability to insert or remove the card with
the computer power turned on. The card is keyed and will
install only in the proper orientation.

Connector for PC Card
Socket on Top Edge

Figure 2-1. The 28.8 Communicator

Identification of Card
(28.8 Communicator)

0153

Connector for Line Access Cable
on Bottom Edge

5

• The Line Access Cable (see Figure 2-2). This cable contains a
connector for the card, a standard jack for a phone line,
and a jack for a handset. The connector and the jacks are
keyed and will install in only the proper orientation.

The connector for the card latches to the card to ensure
continuous connection during use. To remove the cable
from the card, press on the latch-release buttons on both
sides of the connector.

The standard jack for the phone line is the wider jack
connection with only two wires.

The jack for the optional handset is the narrower jack
connection with four wires. The handset is for use with the
modem’s voice capabilities.

NOTE: There is no industry standard for the signal

polarity of handsets; therefore, the handset
jack does not work with all handsets.

To Handset

Connector for a Card

Latch Release
Buttons

Figure 2-2. The Line Access Cable

To phone line

0109

6

The Software

• Communication Software. The communication software
provides the user interface to send and receive data and fax,
and to use the computer as an answering machine. Refer to
the guide that is provided with the communication software
for instructions about the installation and start-up of the
software.

Specifications

The card has the following specifications:

Form Factor

Data Rates

Fax Rates

Data Compression

Error Correction

Data Command Set

Fax Command Set

PCMCIA Type II

CCITT V.34 (28800bps)
CCITT V.32bis (14400bps)
CCITT V.32 (9600bps)
CCITT V.22bis (2400bps)
CCITT V.21 (300bps)
CCITT V.23

(1200/600bps forward, 75bps backward)
Bell 212A (1200bps)
Bell 103 (0-300bps)

CCITT V.17 (14400bps)
CCITT V.29 (9600bps)
CCITT V.27ter (4800bps)

CCITT V.42bis (up to 4:1 compression ratio)
MNP 5 (up to 2:1 compression ratio)

CCITT V.42
MNP 2-4

Enhanced AT command set

CCITT Group 3
Class 1 (EIA-578)
Class 2 (EIA-592)

7

Voice Features

The voice capabilities of the modem allow

you to use your computer as an
answering machine

Diagnostics

Power Consumption

Software Features

16550 UART

Cellular Capability

Power-on self test
Local digital loop test
Local analog loop and analog loop self test
Remote digital loop and digital loop self test

Active mode (off-hook): 975mW
Standby mode (on-hook): 40mW

Operates on systems with:

• PC DOS 5.0 or higher, or
MS-DOS 5.0 or higher

• Windows 3.1

• Card and Socket Services conforming to
PCMCIA Car d and Socket Services
Release 2.1 or higher.

Enhanced UART interface provides

buffering of data. This feature is
essential in providing reliable high
speed communication, when used in
multi-tasking environments like
Windows.

MNP10-EC error correction/data

compression

Simple Technology can reference OEM
cellular interface cables which can connect
the modem to cell phones.

8

3. Installing the Card

This chapter describes checking for Card and Socket Services,
attaching the card, and installing the communication software.

Checking for Card and Socket Services

You must have Card and Socket Services Release 2.1 provided
with your computer installed before using the modem.

Card and Socket Services Release 2.1 are device drivers that handle
all of the detecting, configuring, and enabling of any compatible
PC Card inserted into the system. These device drivers are not
specific to the Simple Technology 28.8 Communicator and will
support other PC Cards as well.

If you know that you already have Card and Socket Services
Release 2.1 installed, proceed to Attaching the Card.

If you do not know if you already have Card and Socket Services
installed, perform the following:

1. While booting your computer, press <F8>. With DOS 6
or higher, this will load the drivers in CONFIG.SYS one
line at a time.

2. When prompted, press “Y” to load each driver and look
for messages indicating that Socket Services Release 2.1
and Card Services Release 2.1 are loading.

NOTE: If Card and Socket Services Release 2.1 did not

load, fill out and mail the enclose coupon for a
free copy. Card and Socket Services Release 2.1
must be installed before proceeding.

If there are existing Card and Socket Services, proceed to

Attaching the Card.

9

Attaching the Card

Perform the following:

1. Orient the modem card with the 68-pin female connector
facing the PC Card socket. Insert the card into the PC
Card socket. The card is keyed and will insert in only the
proper orientation. Some computers will beep when the
computer recognizes the card.

2. Attach the Line Access Cable to the card. The cable
connector is keyed and will only attach in the proper
orientation.

3. Attach a phone line to the wider, two-wire jack in the
Line Access Cable.

4. If you want to use the voice features with local record
and playback, attach a handset to the narrower, four­wire jack in the Line Access Cable.

NOTE: There is no industry standard for the signal

polarity of handsets; therefore, the handset
jack does not work with all handsets.

Proceed to Installing the Communication Software.

Installing the Communication Software

Once you have installed your modem, you can use the
communications software to connect to remote computers,
dial bulletin boards, send electronic mail, send or receive
faxes. Also, the communications software supports the voice
features of the modem. This allows you to use the computer
as an answering machine.

Refer to the User Guide supplied with the communications
software for installation and start-up. Then refer to Configuring
the Communication Software for instructions on setting the com­munication software to the correct IRQ.

10

Configuring the Communication Software

While some expansion slot adapters and built-in COM ports can
share IRQs, PC Cards cannot share IRQs. To avoid sharing IRQs,
the IRQ assigned to your modem by Card and Socket Services may
be set differently than Windows and the communication software
expects. You may have to re-configure the software as follows:

1. Refer to the documentation that came with Card and
Socket Services, and determine the COM port and IRQ
that Card and Socket Services assigns to your modem.

2. You may have to edit the SYSTEM.INI file of Win­dows. Before editing SYSTEM.INI, make a backup of
SYSTEM.INI.

Open SYSTEM.INI with your favorite editor. Find the
same COM port that your modem uses as determined in
Step 1. Then change the IRQ associated with that COM
port so that it is the same as that determined in Step 1.
Save the new SYSTEM.INI, then restart Windows.

3. Next, refer to the guide included with the communication
software and make sure your the communication software
is set to the same COM port and IRQ as determined in
Step 1.

Installation is complete. Proceed to Chapter 4.

11

Notes:

12

4. Using the Card

This chapter provides information on the following topics:

• Inserting and Removing the Card

• About Call Waiting

• Connecting to Cell Phones

• Protecting the Card

Inserting or Removing Your Card

You can insert or remove the card any time the computer is not
accessing the card. Some computers will beep when the computer
recognizes the change in status of the PC Card socket.

About Call Waiting

To ensure that your communications are not interrupted while
using your modem, you should disable call waiting if you have
call waiting. The methods for disabling call waiting vary in
different locations. Instructions for disabling call waiting can
usually be found in the front section of the local telephone
directory.

If disabling call waiting is required, you may want to incorporate
the disabling feature into the standard dialing prefix. For example,
the standard dialing prefix might be ATX4DT. If the call waiting
feature is disabled by ✱70, you may want to change the dial prefix
to ATX4DT ✱70.

Call waiting is normally re-enabled after each call.

13

Connecting to Cell Phones

The card features MNP10-EC standard. This standard provides
the level of error correction needed to reliably connect to the
noisy cell phone environments.

To use the card with a cell phone, you need to purchase a cable
compatible to your brand of cell phone. Refer to the Connecting
the STI Modem to Cell Phones flyer included with the card for
instructions on how to purchase a cable for your cell phone.

To connect the card to a cell phone, substitute the cell phone
cable for the line access cable and follow the instructions in

Chapter 3.

Protecting the Card

Observe the following points:

• Do not drop the card.

• Do not open the card.

• Never remove the card when the computer is accessing the
card.

• Place the computer and peripherals out of direct sunlight,
high or low temperatures, and high humidity.

• Do not turn the computer or peripherals on and off in
rapid succession.

• Keep all vents in the computer and peripherals free from
obstruction, e.g., books, papers, etc.

• Use a power line conditioner in environments where
power surges are likely, e.g., near heavy machinery,
fluorescent lights, etc.

14

5. Using AT Commands

Communications programs control your modem by issuing
modem instructions called AT commands. While it is usually
easiest to let the communication software handle the task of
issuing AT commands, there may be occasions when you will
want to control a series of commands yourself. The information
that follows is included to allow you to tailor your modem for
specific needs.

If you want to send AT commands to your modem directly, you
must be running a data communication program. (You cannot
send AT commands from your operating system prompt.) Once
the communication program is started, you must put it into
terminal mode. Many programs do this automatically. Your
modem must also be in command mode (see Some Notes About
AT Commands) to accept AT command strings. To verify whether
your modem is in the proper mode, type AT <Enter>. If the
modem responds with an OK message, you are all set.

AT commands must:

1. Start with the command string AT

2. Contain one or more of the commands listed in this
chapter

3. End with a carriage return (shown in this book as
<Enter>).

The following notation conventions are used in this chapter:

• AT commands and messages are shown in italics, like so:
AT &F0 <Enter>.

• Factory default settings for commands are shown in bold.
These settings are in effect until you issue a command
altering the setting. For instance, the default setting for Bn
is B1. To return the modem to its factory default settings at
any time, type AT &F0 <Enter>.

• S-registers affected by, or related to, particular AT com­mands are listed in brackets at the end of the command

15

descriptions. Similarly, the AT commands that affect, or are
related to, the contents of an S-register are listed at the end
of each S-register description.

Refer to Table 5-1 for a summary of the basic AT commands.
Refer to AT Commands for the complete list of AT commands

Table 5-1. AT Command Summary

AT Command prefix used to begin almost all commands.
Commands preceded by AT and followed by <Enter>
D Dial the following number using the default or

previous method (tone or pulse).

DT Dial the following number using tones.
DP Dial the following number using pulses.
DS=n Dial stored number n.
W Wait for dial tone before dialing.
H Hang up the phone.
O Go on-line (switch from command mode to data

mode). Used to resume interrupted communications
when the remote modem is still on-line.

Sr? Read S-register r.
Sr=n Write value n to S-register r.
Zn Reset and recall saved profile n.
&Fn Recall factory configuration n.
&V Display current configuration and stored profiles.
&Wn Save current configuration as profile n.
&Zn=x Save x as stored telephone number n.

Command not preceded by AT and not followed by <Enter>
A/ Repeat the previous command.

16

Some Notes About AT Commands

• Some AT commands override other AT commands. For
example, issuing AT &K3 &K4 <Enter> will not enable
both hardware flow control (&K3) and software flow
control (&K4), it will only enable software flow control.
The latter command overrides the former.

• If you do not specify a number on commands that end in a
number, the modem will take the number to be 0. So, for
example, AT B and AT B0 achieve the same effect: setting
communications to the CCITT standard. This feature can
be useful if you wish to save space when issuing com­mands.

• If your modem is on-line and you want to issue an AT
command string to your modem without disrupting your
connection, you can bring your modem into command
mode by typing a special escape sequence. To issue the
escape sequence you must first not transmit any data for a
period equal to the guard time, which by default is one
second. Then type +++ quickly. Do NOT press <Enter>.
Instead, wait for another second. The modem will respond
to this step with an OK message. Now your modem is
ready to accept AT command strings. When you want to
resume your on-line connection, type ATO <Enter>.

17

Configuring the Modem

By default, your modem is set up to automatically detect the
appropriate line speed, use hardwar e flow control, and connect
using error correction and data compression protocols, if possible.
These settings are stored in read-only memory (ROM) at the
factory and can be recovered at any time by issuing the &F0
command, described later in the chapter . If the factory settings do
not meet your needs, (say for instance, your software does not
support hardware flow control), you can define and stor e your
own configurations into nonvolatile memory using the &Wn
command. You can then recover these configurations at any time
with the Zn command. Both &Wn and Zn are described more fully
later in the chapter .

These stored configurations are called profiles. Not all AT
command settings and S-registers can be stored as a part of a
profile. The ones that can be stored are so noted. Several sample
modem configurations are shown below. These are examples of
profiles you might store in memory as your user-definable
profiles. You can store two user-defined profiles.

Sample Configuration 1

One useful configuration is obtained by typing AT &F0 &C1
&D2 &W0 <Enter>. These commands have the following effect:

• &F0 restores the factory default configuration, turning on
line speed detection, hardware flow control, error correction,
and data compression. In other words, if the r emote modem
will allow it, your modem will use all of its most advanced
features.

• &C1 forces the carrier detect (CD) signal to follow the state
of the carrier. This allows your communications software
to properly determine whether the modem is on-line or
off-line.

18

• &D2 instructs your modem to hang up when the data
terminal ready (DTR) signal drops. This will speed up the
hang-up process for most communications software
packages.

• &W0 stores this configuration as profile 0. Now whenever
you type ATZ <Enter>, you will restore this profile.

NOTE: Since your modem will be using hardware flow

control, your communications software must
also be set for hardware flow control. In
addition, to take advantage of the possible 4:1
data compression provided by V.42bis, you
should set your communications package to
lock the DTE rate to the highest speed pos­sible: up to 115200 bps.

Sample Configuration 2

If you are using software that does not support hardware flow
control, then you might use the following configuration: AT &F0
&C1 &D2 &K4 <Enter>.

This configuration is identical to that of the previous example,
except that &K4 is used to enable software flow control rather
than hardware flow control. Note that software flow control
must be used with caution. Do NOT use software flow control
when you are transferring files that might naturally contain
XON and XOFF characters, such as binary files. Also, do not use
software flow control when you are transferring files using
protocols like XMODEM or ZMODEM.

NOTE: If your modem is configured to use software

flow control, then you must also set your
communications software to use software flow
control.

19

Sample Configuration 3

If your software does not support hardware flow control, but
you would like to transfer files with a protocol like XMODEM or
ZMODEM, you should try configuring your modem as follows:
AT &F0 &C1 &D2 &K0 &Q0 \J1 <Enter>.

The first three commands are the same as described in the first
example. &K0 turns off all flow control. &Q0 specifies a direct
connection, which is a connection without flow control, data
compression, or error correction. \J1 forces the data terminal
equipment (DTE) rate to match the data communication equip­ment (DCE) rate, which is required when all flow control is
disabled. In this case, you must set your terminal speed to match
the line speed, e.g., 14.4 Kbps.

This configuration is not reliable for high-speed connections
unless transferring files with newer XMODEM or ZMODEM
protocols: XMODEM and ZMODEM protocols have error
correction built into them. Also, to ensure that file transfer is
reliable, make sure that the protocol does not use packet sizes
that are too large.

20

AT Commands

This section list the AT commands that the modem uses. This
listing is organised by the nonalphabetic first character after
“AT” (i.e., no letter, &, %, \, ), @, *, :, and -), and then in
alphanumeric order. The default settings are listed in bold.

A Answer Command. This command causes the modem

to attempt to answer an incoming call. The modem will
make its attempt regardless of whether the modem is in
auto-answer mode or not. This command should be
issued after the RING result code is seen (when another
modem is attempting to connect).

A/ Re-executes the previous command line. This command is

NOT preceded by AT or followed by <Enter>.

Bn CCITT/Bell Setting. This command selects either the

CCITT standard or the Bell standard for 300 and 1200 bps
communications. (See S27.)

B0 CCITT V.22 for 1200bps, CCITT V.21 for 300bps.

B1 BELL 212A FOR 1200BPS, BELL 103 FOR 300BPS.

C1 Carrier Control Command. This command is included for

compatibility only and performs no function other than to
return an OK message.

21

Dn Dial Command. This command directs the modem to

go off-hook, wait for a dialtone, and dial the number
indicated in the dial string, n. The dial string may
contain the characters 0-9 for pulse-mode dialing or 0-9,
A-D, *, and # for touch-tone dialing. Spaces, hyphens,
and parentheses can be included in the command to
improve readability. For example, D [phone] and
D1234567890 are equivalent.

In addition, the dial string may contain these dial com­mand modifiers:

L Redial the last valid number entered.
P Pulse-mode dialing. (See S14.)
T Touch-tone dialing. (See S14.)
S=n Dial 1 of 4 stored telephone number, where n is 0, 1,

2, or 3. (See &Zn)
W Wait for a second dialtone. (See S7.)
, Pause before dialing the digits that follow. (See S8.)
@ Wait for quiet answer. Wait for one or more rings

followed by at least five seconds of silence before

continuing with execution of the dial string. This is

useful for transferring calls on some PBX systems.
; Return the modem to command state. When placed

at the end of the dial string, this puts the modem

into command mode. While in command mode, the

modem will not attempt to connect with the remote

modem.

22

! Put the modem briefly on-hook. This can be useful

for transferring calls on some telephone systems.

(See S29.)
^ Turn off calling tone while originating this call only.
J Perform MNP10 link negotiation at 1200 bps for this

call only (see *H).

K Enable power level adjustment during MNP 10 link

negotiation for this call only (see “)Mn”).
& Wait for credit card bong before continuing with the

dial string. If the bong is not detected within the

time specified in S7, the dial string will be aborted,

dialing terminated, and an error message generated.

En Local Echo Setting. This command determines whether the

commands you type are echoed to the screen. (See S14.)
E0 Disable command echo.

E1 ENABLE COMMAND ECHO.

NOTE: If you see duplicate characters, then both your

modem’s local echo and your application
software’s local echo are enabled.

23

Fn Line Connection Speed Setting. This command is not

supported. Use N0 and S37 to force connect mode.

Hn Hang-up Command.

H0 On-hook (hang up).
H1 Off-hook.

In Identification Command.

I0 Report product code (e. g. 28800).
I1 Report read-only memory (ROM) checksum. This

number should always remain the same.

I2 Reports OK.
I3 Report ROM revision level.
I4 Report modem identifier string.
I5 Report country code (e.g. 022 for U.S.).
I6 Report data pump model and code revision.
I7 Reports DAA code for external DAA (if not in-

stalled, reports 255)

Ln Speaker Volume Setting. (See also register S22.) On

PCMCIA modems, there may be no discernable difference
between volume levels.

L0 Off.
L1 Low.
L2 Medium.

L3 High.

Mn Speaker Control Setting. This command controls when the

speaker will be on or off. (See also S22.)
M0 Always off.

M1 On during call establishment, off after receiving

carrier.

M2 Always on, even during data transmission.
M3 On between dialing and carrier detection.

24

Nn Automatic Line Speed Detection Setting. (See also S31,

S37, and Fn.)
N0 Automatic line speed detection disabled. Handshak-

ing will be conducted according to the contents of

S37.

N1 Automatic line speed detection enabled.

On On-line Command. This command switches the modem

from command mode to on-line mode. If there is no
established connection, ERROR is returned.

O0 Go back on-line without a retrain.
O1 Go back on-line after initiating a retrain.

P Pulse-mode Dial Setting. This setting specifies pulse-mode

dialing for all subsequent connections. (See S14, contrast
with T.)

Qn Result Code On/Off Setting. This command determines

whether or not the modem returns result codes such as
OK, ERROR, or CONNECT. (See S14, S95, Vn, Wn, Xn.)

Q0 Display result codes.

Q1 Do not display result codes.

Sn? Read S-register. This command enables you to read the S-

register specified by the number n. For example, typing

ATS0? <Enter> will allow you to view the contents of the
S0 register.

Sn=x Write to an S-register. This command allows you to change

the contents of an S-register. For example ATS0=2 <Enter>
writes the value 2 to the S0 register. Note that the modem
does not perform error checking on values written to S­registers. It will always return the OK message. (See S-
Registers for details on the contents of each S-register.)

T Touch-tone Dial Setting. This setting specifies touch-

tone dialing for all subsequent connections. (See S14,

contrast with P.)

25

Vn Result Code Format Setting. (See S14, S95, Qn, Wn, Xn.)

V0 Numeric result codes.

V1 Verbose result codes.

Wn Connection Message Setting. If you change the value of

S95, it may override the Wn setting. (See S31, Vn, Qn.)

W0 Report DTE rate only. For example:

CONNECT 57600
W1 Report DCE rate, error correction protocol, and DTE

rate. For example:

CARRIER 14400

PROTOCOL: LAPM

CONNECT 57600
W2 Report DCE rate only. For example:

CONNECT 14400

Xn Extended Result Code Setting. This command selects

which call progress result codes are reported. (See S22,

S95, Qn, Vn, Wn, and “Result Codes and Messages.”)
X0 Send basic call progress result codes: OK, CONNECT,

RING, NO CARRIER, ERROR, NO ANSWER.
X1 Same as X0 but also report rate-specific CONNECT

messages.
X2 Same as X1 but also report NO DIALTONE detec-

tion.
X3 Same as X2 but also report BUSY signal detection.

X4 Send all call progress messages.

26

Yn Long Space Disconnect Setting. This command determines

whether the modem hangs up when it receives a long
space signal (greater than 1.6 seconds) from the remote
modem. If enabled, the modem will send a 4 second space
signal to the remote modem before hanging up. (See S21.)

Y0 Disable long space disconnect.

Y1 Enable long space disconnect.

Zn Modem Reset/Restore Profile Command.

Z0 Perform modem reset and restore configuration

profile 0.
Z1 Perform modem reset and restore configuration

profile 1.

AT& Commands

&Cn Carrier Detect (CD) Signal Setting. (See S21.)

&C0 CD always on.

&C1 CD follows state of carrier.

&Dn Data Terminal Ready (DTR) Signal Setting. This com-

mand affects the interpretation of the DTR signal. Note
that when the modem is on-line, it ignores a DTR drop
that lasts less than the value in S25, .05 seconds by
default. (See also S21.)

&D0 DTR is ignored.
&D1 A DTR drop causes the modem to go into command

mode.

&D2 Auto-answer is inhibited and a DTR drop causes

the modem to hang up.

&D3 a DTR drop causes the modem to perform a soft

reset.

27

&Fn Restore Factory Profile Command. This command will

restore one of the two preset factory profiles. These
profiles enable automatic line speed detection, hardware
flow control, error correction, and data compression.

You can also define and store your own specialized
profiles. See the &Wn, &Yn, and Zn commands for details.

&Gn Guard Tone Setting. This command sets the guard tone for

V.22 and V.22bis connections. (See S23.)

&G0 No guard tone.

&G1 No guard tone.
&G2 1800 Hz guard tone. Used in the U.K. and some

other Commonwealth countries.

&Jn Telephone Jack Setting. The &J0 and &J1 commands are

included for compatibility only and perform no function
other than to return an OK message.

&Kn Flow Control Setting. If your communications software

does not support hardware flow control, you will need to
specify &K0 or &K4 (see below). (See S39.)

&K0 Disable flow control.

&K3 Enable hardware flow control only.

&K4 Enable software flow control only.
&K5 Enable transparent software flow control.
&K6 Enable both hardware and software flow control.

&L Leased Line Setting. The &L0 command is included for

compatibility only and performs no function other than to
return an OK message. This modem does not support
leased line operation.

&M Selects a direct connection. This command is equivalent to

&Q0.

28

&Pn Pulse Dial Make/Break Ratio Setting. Enabled on a per

country basis. If enabled the dial make/break ratio is as
follows:

&P0 39%-61% dial ratio at 10 pulses per second.

&P1 33%-67% dial ratio at 10 pulses per second.
&P2 39%-61% dial ratio at 20 pulses per second.
&P3 33%-67% dial ratio at 20 pulses per second.

&Qn Asynchronous Mode Setting. (See S27 and S36.)

&Q0 Selects a direct connection.
&Q1 Reserved.
&Q2 Reserved.
&Q3 Reserved.
&Q4 Reserved.

&Q5 Selects a reliable connection. The value in S36 will

determine whether or not a failure to establish a

particular error correction link will result in the

modem hanging up or trying to make another type

of connection. (See also \N2, \N3, \N4, and \N5.)

&Q6 Selects normal connection. (Equivalent to \N0.)

&Rn Hardware Flow Control Setting. This command selects

how the modem controls its Clear to Send (CTS) signal if
hardware flow control is selected. (See S21.)

&R0 CTS always on.

&R1 CTS will drop only if required by flow control.

&Sn Data Set Ready (DSR) Signal Setting. (See S21.)

&S0 DSR always on.

&S1 DSR is active after an answer tone has been detected

and inactive after the carrier has been lost. Very few

communications packages require this setting.

29

&Tn Diagnostic Test Commands. This set of commands

provides diagnostic tests that comply with the CCITT
V.54 recommendations. All connections established
during testing must be normal or direct connections.
(See S16, S18.)

&T0 Terminate test in progress. Generally during a test the

modem is on-line. Therefore to issue this command

you will need to type the escape sequence +++ and

wait for the OK message. You can then type A T&T0

<Enter> to terminate the test. Alternatively, if S18 is

nonzero, a test will terminate automatically after the

number of seconds specified in S18.
&T1 Local analog loopback test. This test checks the

operation of your modem’s transmitter and re-

ceiver.

For example:

1. Your modem should be on-hook and in
command mode. Type AT\N0 <Enter>. This
specifies a normal connection.

2. Type AT S18=10 <Enter>. This specifies a test
period of 10 seconds.

3. Type AT &T1 <Enter>. This initiates the local
analog loopback test.

4. Type a simple character pattern. If your
modem is working properly, you will see this
character pattern echoed to the screen.

5. The test will end automatically after 10
seconds.

6. Return your modem to its original state by
typing ATZ <Enter>.

&T2 Reserved.

30

&T3 Local digital loopback test. This test verifies the

operation of two connected modems and the phone
channel.

For example:

1. Your modem should be on-hook and in
command mode. Type AT\N0 <Enter>. This
specifies a normal connection.

2. Type AT S18=10 <Enter>. This specifies a test
period of 10 seconds.

3. Establish a connection with the remote
modem by typing ATDnnn-nnnn <Enter>.
Wait for the CONNECT message.

4. Issue the escape sequence to put the modem
back into command mode (type +++ without
pressing <Enter>). When you see the OK
message, your modem is in command mode.

5. Issue the command AT &T3 <Enter>. This
initiates the local digital loopback test.

6. Have someone at the remote modem type a
simple character pattern. This character
pattern then loops through your modem back
to the remote modem. Everything is working
properly if the original character pattern is
echoed back to the remote user’s screen.

7. The test will end automatically after 10
seconds.

8. When your testing is complete, hang up the
line and return your modem to its original
state by typing ATHZ <Enter>.

&T4 Allows local modem to accept a request from the

remote modem for a remote digital loopback test.
(See S23.)

31

&T5 Prohibits local modem from accepting a request

from the remote modem for a remote digital
loopback test. (See S23.)

&T6 Remote digital loopback test. This test verifies the

operation of two connected modems and the phone
channel.

For example:

1. Your modem should be on-hook and in
command mode. Type AT\N0 <Enter>.

2. Type AT S18=10 <Enter>. This specifies a test
period of 10 seconds.

3. Establish a connection with the remote
modem by typing AT Dnnn-nnnn <Enter> .
Wait for the CONNECT message.

4. Issue the escape sequence to put the modem
back into command mode (type +++ without
pressing <Enter>). When you see the OK
message, your modem is in command mode.

5. Issue the command AT &T6 <Enter>. This
initiates the remote digital loopback test. Note
that the remote modem must support CCITT
V.54 and must be prepared to accept the
request for this test. (See &T4.)

6. Type a simple character pattern and verify that
what you type is echoed correctly to your
screen.

7. The test will end automatically after 10
seconds.

8. When your testing is complete, hang up the
line and return your modem to its original
state by typing ATHZ <Enter>.

32

&T7 Remote digital loopback with self-test. This test

verifies the operation of two connected modems and
the phone channel. It sends an internal test pattern
through the loop and returns a numeric message
that indicates the number of errors that were
counted during the test period. (See &T6.)

For example:

1. Your modem should be on-hook and in
command mode. Type AT \N0 <Enter>.

2. Type AT S18=10 <Enter>. This specifies a test
period of 10 seconds.

3. Establish a connection with the remote
modem by typing AT Dnnn-nnnn <Enter> .
Wait for the CONNECT message.

4. Issue the escape sequence to put the modem
back into command mode (type +++ without
pressing <Enter>). When you see the OK
message, your modem is in command mode.

5. Issue the command AT &T7 <Enter>. This
initiates the remote digital loopback with
self-test. Note that the remote modem must
support CCITT V.54 and must be prepared
to accept the request for this test. (See &T4.)

6. The test will end automatically after 10
seconds. The number of errors that were
counted are displayed on your screen at the
end of the test. 000 means that there were no
errors. 255 means that there were 255 or more
errors.

7. When your testing is complete, hang up the
line and return your modem to its original
state by typing ATHZ <Enter>.

33