Sierra Wireless MP 700 Series Command Reference Manual

MP 700 Series GPS
Rugged Wireless Modem

AT Command Reference

2130309

Rev 3.2

Preface

Important Notice

Safety and Hazards

Because of the nature of wireless communications, trans­mission and reception of data can never be guaranteed. Data
may be delayed, corrupted (i.e., have errors) or be totally lost.
Although significant delays or losses of data are rare when
wireless devices such as the Sierra Wireless modem are used in
a normal manner with a well-constructed network, the Sierra
Wireless modem should not be used in situations where
failure to transmit or receive data could result in damage of
any kind to the user or any other party, including but not
limited to personal injury, death, or loss of property. Sierra
Wireless, accepts no responsibility for damages of any kind
resulting from delays or errors in data transmitted or received
using the Sierra Wireless modem, or for failure of the Sierra
Wireless modem to transmit or receive such data.

Do not operate the Sierra Wireless modem in areas where
blasting is in progress, where explosive atmospheres may be
present, near medical equipment, near life support equipment,
or any equipment which may be susceptible to any form of
radio interference. In such areas, the Sierra Wireless modem
MUST BE POWERED OFF. The Sierra Wireless modem can
transmit signals that could interfere with this equipment.

Do not operate the Sierra Wireless modem in any aircraft,
whether the aircraft is on the ground or in flight. In aircraft, the
Sierra Wireless modem MUST BE POWERED OFF. When
operating, the Sierra Wireless modem can transmit signals that
could interfere with various onboard systems.

Note: Some airlines may permit the use of cellular phones while the
aircraft is on the ground and the door is open. Sierra Wireless
modems may be used at this time.

The driver or operator of any vehicle should not operate a
computer or any other device connected to the Sierra Wireless
modem while in control of a vehicle. Doing so will detract
from the driver or operator's control and operation of that
vehicle. In some states and provinces, operating such commu­nications devices while in control of a vehicle is an offence.

Limitation of
Liability

Rev 3.2 Oct.05 1

The information in this manual is subject to change without
notice and does not represent a commitment on the part of
Sierra Wireless. SIERRA WIRELESS AND ITS AFFILIATES
SPECIFICALLY DISCLAIM LIABILITY FOR ANY AND ALL
DIRECT, INDIRECT, SPECIAL, GENERAL, INCIDENTAL,
CONSEQUENTIAL, PUNITIVE OR EXEMPLARY DAMAGES
INCLUDING, BUT NOT LIMITED TO, LOSS OF PROFITS OR

MP 700 Series GPS AT Command Reference

REVENUE OR ANTICIPATED PROFITS OR REVENUE
ARISING OUT OF THE USE OR INABILITY TO USE ANY
SIERRA WIRELESS PRODUCT, EVEN IF SIERRA WIRELESS
AND/OR ITS AFFILIATES HAS BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES OR THEY ARE
FORESEEABLE OR FOR CLAIMS BY ANY THIRD PARTY.

Notwithstanding the foregoing, in no event shall Sierra
Wireless and/or its affiliates aggregate liability arising under
or in connection with the Sierra Wireless product, regardless of
the number of events, occurrences, or claims giving rise to
liability, be in excess of the price paid by the purchaser for the
Sierra Wireless product.

Patents

Copyright

Trademarks

Portions of this product may be covered by some or all of the
following US patents:
5,515,013 5,629,960 5,845,216 5,847,553 5,878,234
5,890,057 5,929,815 6,169,884 6,191,741 6,199,168
6,339,405 6,359,591 6,400,336 6,643,501 6,516,204
6,561,851 6,653,979 6,697,030 6,785,830 6,845,249
6,847,830 6,876,697 6,879,585 6,886,049 D442,170
D459,303 and other patents pending.

Manufactured or sold by Sierra Wireless or its licensees under
one or more patents licensed from InterDigital Group.

Licensed under the following Nortel Networks Limited
patents:
United States patent numbers: 5128925, 5398247
France patent numbers: 2665993, 2653959, 2659812, 2745091

© 2005 Sierra Wireless. All rights reserved.

AirCard and “Heart of the Wireless Machine” are registered
trademarks of Sierra Wireless.
Sierra Wireless, the Sierra Wireless logo, the red wave design,
the red-tipped antenna, and Watcher are trademarks of Sierra
Wireless.

Windows® is a registered trademark of Microsoft Corporation.

Other trademarks are the property of the respective owners.

2 2130309

Contact
Information

Preface

Sales Desk: Phone: [phone]

Hours: 8:00 AM to 5:00 PM Pacific Time
e-mail: [e-mail]

Technical Support: e-mail: [e-mail]

Web: www.sierrawireless.com/

developers

Post: Sierra Wireless, Inc.

13811 Wireless Way,
Richmond, BC
Canada V6V 3A4

Fax: [phone]

Web: www.sierrawireless.com

Your comments and suggestions on improving this documen­tation are welcome and appreciated. Please e-mail your
feedback to

[e-mail]. Thank you.

Consult our website for up-to-date product descriptions,
documentation, application notes, firmware upgrades, trouble­shooting tips, and press releases:

www.sierrawireless.com

Rev 3.2 Oct.05 3

MP 700 Series GPS AT Command Reference

4 2130309

Table of Contents

About This Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Terminology and acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Currency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Upgrading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Document Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Modem Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

GSM, GPRS, and EDGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Establishing a communication session. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Host connection basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Hardware structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Host and network connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Modem modes, states, and conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Connection Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

State Transitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Command to data state . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Data to command state . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Modem Buffers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Command buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Data buffers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Command Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Concatenation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Rev 3.2 Oct.05 5

MP 700 Series GPS AT Command Reference

Responses and Result Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Possible result codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Human vs. machine interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Response and Result Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Response framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Result code framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

GPS data format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Command Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Command Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Standard Modem Commands (V.25ter) . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

GSM Voice and Circuit-Switched Data Commands (GSM 07.07) . . . . . . 26

SMS Commands (GSM 07.05) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

GPRS Packet Data Commands (GSM 07.07) . . . . . . . . . . . . . . . . . . . . . . . 28

EDGE Data Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Modem Control Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Command Reference Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Status Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

Result Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

Basic Result Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

Factory Default Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

6 2130309

1: About This Guide

• Introduction

• References

• Currency

• Document Structure

• Conventions

Introduction

This reference details the Attention (AT) command set
supported by the MP 700 Series GPS rugged wireless modem.

1

Note: For additional background
on the use of modems and AT
commands generally you may
consult the University of
Manitoba web site at:

www.umanitoba.ca/campus/acn/
remote/faq/at-cmds.html.

You should be familiar with the use of AT commands with
standard wireline modems to use this document.

The Sierra Wireless GSM products present two methods of
controlling the modem: AT commands and CnS (Control and
Status) language. Some features or capabilities of the modem
require the use of CnS. This document presumes that the AT
interface is the only interface available to you; features
requiring CnS are not discussed.

References

This guide covers only the command set used by the
MP 700 Series GPS and does not deal with operational use.
Refer to the product documentation for instructions on using
your modem.

Not all commands include detailed descriptions. Commands
are implemented to be compliant with industry standards and
reference is often made to the following standards:

• IS-131 (Data Transmission Systems and Equipment -

Extensions to Serial Asynchronous dialing and Control)

• EIA/TIA-592 (Asynchronous Facsimile DCE Control

Standard, Service Class 2)

• EIA/TIA/IS-134 (Amendments to TIA-592 to Support T.30-

1993 (Facsimile protocol standard))

Electronic copies of these standards can be purchased at the
ANSI Electronic Standards Store at:
Customer Service will respond to inquiries about standards
information at:

Requests for hard copies of standards should be directed to the
Global Engineering Documents Division of Information
Handling Services:

voice: 800-854-7179 or 303-397-7956

Rev 3.2 Oct.05 7

[e-mail].

webstore.ansi.org. ANSI

MP 700 Series GPS AT Command Reference

fax: [phone]

e-mail: [e-mail]

web: http://global.ihs.com

post: Global Engineering Documents,

Global Engineering operates offices around the world. Consult
the web site above for locations.

Other standards referenced in this document are available
through the 3rd Generation Partnership Project (3GPP) web
site at
Union Standards Division (ITU-T) at

• ETSI TS 100 916 V7.5.0 (1999-12) (AT Command Set for

• V. 2 5 ter (ITU-T recommendation V.250), GSM 07.07, and

• 3GPP TS 24.008: 3rd Generation Partnership Project; Mobile

15 Inverness Way East,
Englewood, CO 80112

www.3gpp.org, and the International Telecommunications

www.itu.int. They include:

GSM Mobile Equipment)

GSM 07.05 standards

Radio Interface Layer 3 specification; Core Network Protocols­Stage 3

Note: For additional background
on the use of modems and AT
commands generally you may
consult the University of
Manitoba web site at:

www.umanitoba.ca/campus/acn/
remote/faq/at-cmds.html.

You may also want to consult the other documents available
on the Sierra Wireless web site at

www.sierrawireless.com.

Terminology and acronyms

This document makes wide use of acronyms that are in
common use in data communications and cellular technology.
Our Internet site provides a Glossary (document #2110032)
that may be helpful in understanding some acronyms and
terminology used in this guide.

Currency

This document is current with version R2_2_7ap of the
MP 750 GPS firmware and version R3_1_2ap of the
MP 775 GPS firmware.

Upgrading

If your modem firmware is an earlier version, you can acquire
updated firmware from our web site
(www.sierrawireless.com) or by contacting your wireless
carrier.

8 2130309

About This Guide

Document Structure

Following this introduction is a section on basic elements
important to understanding and communicating with the
MP 700 Series GPS. This includes notes on the connection
between the host computer and the modem.

The document then presents the commands, registers, result
codes, and defaults provided in the command state of the
modem.

Commands are often termed AT commands. Hayes™ origi­nated the convention of prefixing commands with an
“ATtention” string for wireline modems.

In addition to the commands, this document also describes the
definitions and use of status registers.

Commands are referenced in strict alphabetical order. This
facilitates searches for the syntax, parameters, and operation of
specific commands. To help locate whether or not a command
exists to perform a desired function, there are tables
organizing the commands into groups.

Descriptions of the definitions and use of status registers, as
well as a table of the factory/reset defaults, follow, along with
result codes, both numeric and verbose.

Conventions

The following format conventions are used in this reference:

• Character codes or keystrokes which are described with

words or standard abbreviations are shown within angle
brackets using a different font: such as
Return and

• Numeric values are decimal unless prefixed as noted

below.

• Hexadecimal values are shown with a prefix of 0x, i.e. in

the form 0x3D.

• Binary values are shown with a prefix of 0b, i.e. in the form

0b00111101.

• Command and register syntax is noted using an alternate

font:

Note: The AT characters must be included before all commands,
except as noted in the reference tables.

<space> for a blank space (spacebar) character.

ATD6045559010.

<CR> for Carriage

Rev 3.2 Oct.05 9

MP 700 Series GPS AT Command Reference

• Characters that are required are shown in uppercase;

• Supported parameter values (either set or returned) are

Note: The brackets shown with parameters are not to be included in
the command string.

The default settings are noted in the command tables. Note
that these are the factory default settings and not the default
parameter value assumed if no parameter is specified. The
factory defaults are also noted in a section at the end of the
Commands chapter, on page 107.

Result Code This is a numeric or text code that is returned
after all commands (except resets). Only one result code is
returned for a command line regardless of the number of
individual commands contained on the line.

parameters are noted in lowercase. Parameters are
enclosed in angle brackets (

<i>) to indicate that they should

be replaced with a value. Optional parameters are
described in the text, and may also be enclosed in square
brackets (

[<m>]) for clarity.

described in the text.

Response This term indicates a response from the modem
that is issued prior to a result code. Reading registers or
issuing commands that report information will provide a
response followed by a result code unless the command
generates an error.

See page 20 for a discussion of how the modem frames these
two elements.

In this document, responses and result codes from the modem,
or host system software prompts, are shown in this font:

CONNECT 14400
OK

10 2130309

2: Modem Basics

• GSM, GPRS, and
EDGE

• Modem modes, states,
and conditions

• State Transitions

• Modem Buffers

• Command Handling

• Responses and Result
Codes

• Response and Result
Framing

• GPS data format This section provides the information required to:

• Establish a communications session with the modem that

will allow you to enter AT commands

• Understand the operating modes and states of the modem

and what causes the modem to transition between them

• Understand which commands are available during

connections and which are not

• Understand how the modem’s results and responses are

framed and change the framing where required

2

GSM, GPRS, and EDGE

The MP 700 Series GPS operates on GSM network technology.
GSM (Global System for Mobile communications) is a type of
wireless communications network designed for mobile phones
that is widely deployed throughout the world. GPRS (General
Packet Radio Service) and EDGE (Enhanced Data rates for
GSM Evolution) are add-on data services to GSM networks.
GPRS provides a maximum data transmission speed of
56 kbps while EDGE provides a maximum data transmission
speed of 216 kbps. The MP 750 GPS supports GPRS while the
MP 775 GPS supports GPRS and EDGE service.

GPRS service has been implemented on most GSM networks
but there are a few areas (mainly rural areas in Europe) with
GSM coverage but no GPRS service. EDGE is less widely
implemented. The MP 700 Series GPS modem is primarily
designed to provide GPRS/EDGE data connections but the
modem can also be configured (using the Fallback feature) to

Rev 3.2 Oct.05 11

MP 700 Series GPS AT Command Reference

establish CSD (Circuit-Switched Data) connections in areas
that have GSM but no GPRS/EDGE service (assuming CSD is
supported by your service provider).

Establishing a communication session

Any terminal emulation program can be used to create a
communications session that will allow you to issue AT
commands to the modem. This section describes how to use
HyperTerminal, a program typically installed with Windows,
to establish a session with the modem.

To establish the communications session:

1. If the modem is not already connected to a serial port on

2. If open, close Watcher (or any other program that commu-

3. Launch HyperTerminal. (Depending on your version of

4. Enter any name and select any icon in the Connection

5. Select the COM port to which the modem is connected

6. Select these port settings:

your computer, connect it.

nicates with the modem).

Windows and how it was installed, you can launch the
program by selecting

Communications > HyperTerminal

Description window and click

(usually

· Bits per second 115,200

· Data bits 8

· Parity None

· Stop bits 1

· Flow control Hardware

Click OK.

COM1) in the Connect using field, and click OK.

Start > Programs > Accessories >

.)

OK.

To verify that the communications session is functional, enter

AT. The modem should respond with OK.

12 2130309

Modem Basics

Host connection basics

Hardware structure

The MP 700 Series GPS has two main components: the
AirCard® wireless network card and the controller board.
Each of these components has its own firmware (resident
software). There is a serial link between the AirCard and the
controller board.

All AT commands that begin with AT!MP are handled by the
controller board and all others are handled by the AirCard.

Host-to-modem

connection

It is important to recognize these two command types because
during modem-to-network connections, the MP 700 Series GPS
does not respond to AirCard AT commands. (That is, only

AT!MP commands will work.) This means that it is not possible

to, for example, check the signal strength using the command

AT!RSSI? during a modem-to-network connection.

Host and network connections

When the MP 700 Series GPS is used to access Internet services
or retrieve data over a VPN connection, two connections are
required: the host-to-modem connection and the modem-to-

network connection.

Modem-to-network

connection

Rev 3.2 Oct.05 13

MP 700 Series GPS AT Command Reference

Modem-to-network connection

Note: If you are developing a
network application to control or
monitor MP 700 Series GPS
modems installed in a fleet of
vehicles, it is usually best to use
Always On mode. (With On
Demand mode, it can be difficult
to track the modems’ IP
addresses.)

Note: The AT command
AT!MPOPMODE is used to set
the operating mode.

The operating mode determines how the modem-to-network
connection is established. In

Always On mode, the modem-to-

network connection is established whenever the modem is

powered and GPRS/EDGE service is available. In

On Demand

mode, the modem-to-network connection is established only
when the host-to-modem connection is requested.

Regardless of the operating mode, the modem-to-network
connection is established as needed, if the modem has been
configured to send MTP data. (See the

AT!MPMTCONF

command on page 50.)

Host-to-modem connection

The MP 700 Series GPS supports serial and USB host connec­tions. To issue AT commands to the modem, the serial
connection is required. Having a USB connection in addition to
the serial connection has two main advantages:

• USB provides a higher data rate between the host and the

modem

• With a USB connection, the modem connects instantly to

the network on startup. With only a serial connection, you
must establish the connection using Watcher or Windows
DUN (Dial-Up Networking.) With a USB host connection,
and the operating mode set to

Always On, it is not necessary

to run Watcher or DUN to make connections.

If you intend to have both a serial and USB connection, you
must install the modem using the USB option. (When you
install the modem software, you are prompted to indicate
whether you are using a serial or USB connection. When you
select the USB option, both the serial and USB drivers are
installed.) If you install the modem using the serial option and
then connect a USB cable, the host computer will not be able to
communicate with the modem.

Modem modes, states, and conditions

This document uses the words mode (circuit-switched data,
packet-switched data, fax, or voice), state (command or data), and
condition (online or offline)

status.

to describe the modem’s operational

14 2130309

Modem Basics

Connection Modes

The MP 700 Series GPS operates in three modes:

Circuit-switched data (CSD) In Circuit Switched Data
(CSD) mode, the modem operates much like a landline
modem.

The Fallback feature must be configured to allow for this type

of connection. (See

Packet-switched data In this mode the modem establishes a

high-speed packet data connection using GPRS or EDGE service.

Voice If your account allows for it, you can attach a headset to

your modem and use it as a mobile phone. You require a 4-wire
headset with a 2.5 mm connector, to use your modem as a phone.

(This plugs into the Audio connector on the back of the
modem. You may need an extension cable if the modem is
installed in the trunk. Contact your service provider to
determine what extension cables are supported.)

!MPFBSETUP on page 41.)

States

The modem’s state indicates what form of communication is
occurring between the modem and the host computer.

At any time the modem is in one of two states:

Command The modem exchanges data with the host
computer as AT commands and replies. During voice commu­nications the modem is always in command state.

Data The modem exchanges computer data with the host.

Note: The modem cannot be in voice mode and data state. Even
while off-hook with a voice call active, the modem still communicates
over the serial connection in command state. Commands can be
issued and executed while a voice call is in progress.

Conditions

The modem’s condition indicates whether there is a network
connection (airlink). At any time, the modem is in one of two
conditions:

Online Actively connected to a remote terminal or network
(off-hook). In the online condition, the modem can either be in
command state or in data state.

Rev 3.2 Oct.05 15

MP 700 Series GPS AT Command Reference

Offline Disconnected from any remote terminal or network
(on-hook). While in offline condition, the modem can only be
in command state (without an airlink).

The following tables show the possible combinations of
modes, states, and conditions:

Table 2-1: Functional combinations of modem state
and mode

CSD Mode Yes Yes
GPRS Mode Yes Yes
Voice Mode Yes No

Table 2-2: Functional combinations of modem state
and condition

Online Condition Yes Yes
Offline Condition Yes No

Command State Data State

Command State Data State

State Transitions

The auto connect feature (see !MPPADSETUP on page 54) deter­mines what state is established when the modem is powered:

• If autoconnect is enabled, on start-up the modem is in data

state. (A PAD session is established, but not necessarily an
Internet connection.)

• If autoconnect is disabled, on start-up the modem is in

command state.

Command to data state

Note: A transition to command
state from data state does not
require that the session be
closed. This means that DCD will
remain asserted while the
modem is in command state,
online condition.

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The modem changes from command to data state when a
session is opened either by dialing a connection, or by
answering a data call. When a session opens, the modem
issues the
setting (see page 58), asserts the DCD control signal.

CONNECT message and, depending on the DCD

Data to command state

The modem changes from data to command state when:

• The DTR de-asserts (depending on settings made, &D1 or

&D2).

• The modem is reset or power-cycled (if autoconnect is

disabled).

Modem Basics

• If there is an active PAD (Packet Assembler/Disassembler)

session and the PAD is configured to use TIES (Time
Independent Escape Sequence), the modem switches to
command state on receipt of “
in upper case.) The command !MPPADCONF (described
on page 52) is used to enable and disable TIES.

When the modem changes to command state, it will issue an OK
result. This may be preceded by another result (such as

CARRIER

outside the modem. The modem returns to command state when
a session is closed.

) to indicate that the session was closed by an event

AT+++”. (The “AT” must be

NO

Modem Buffers

Communication between the host and modem is buffered
based on the modem’s state.

Command buffer

When in command state, the modem buffers the input from
the host until a
edited using the backspace
enabled) echoes the sequence
readability.

<CR> is entered. The buffered data can be

<BS>. The modem (unless Echo is

<BS><space><BS> for human

There is a limit of 200 characters to one command line,
including the
characters of useful command buffer). If the command buffer
length is exceeded the modem will continue to echo input
(which is not buffered) until the

<CR> is entered, the modem returns the ERROR result code

without executing any commands in the line. Once over the
limit, the

ERROR code is still returned.

The command buffer is distinct from the data receive and
transmit buffers. The command buffer retains the contents of
the last issued command until the
received for the next command. This allows repeating of the
last issued command by entering

AT prefix and the <CR> termination (i.e. 197

<CR> is received. When the

<BS> will not bring you back under the limit; the

AT command prefix is

A/.

Data buffers

Data being transmitted or received is buffered in several ways
depending on the mode and nature of the connection. Some
caution must be taken when disconnecting to ensure that any
buffered data in the modem has been properly processed prior
to breaking the connection.

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MP 700 Series GPS AT Command Reference

Specific settings for buffer controls are described in the
relevant commands and registers. Normal configuration of the
modem will not require you to adjust these settings.

Data flow control The modem’s CTS and RTS lines control
data flow. Where large amounts of data are being exchanged,
local hardware flow control must be used to prevent buffer
overflows; it is required for PPP connections. Hardware flow
control is enabled by default. (See the
page 98).

Command Handling

AT can be issued as a command without parameters. It acts like

a “ping” to the modem and always gives a result code of
(unless quiet mode is enabled).

Commands are not case-sensitive; they may be entered in
upper or lower case, or a combination. Arguments to
commands may be case-sensitive.

+IPR command on

OK

Note: When concatenated
together, AT commands may not
function predictably. It is best to
avoid concatenating commands
without first testing and verifying
the results.

Concatenation

More than one command can be included in a single line,
although some commands or their parameters must be placed
at the end of the line. When concatenating commands, a space
between basic commands is optional. Where extended
commands (those beginning with a non-alphabetic character
after the
semicolon (

Commands are executed in the order entered. If a command
results in the
line is ignored. Only one result code is returned for the entire
command line. The complete concatenated command string
must not exceed the
page 17).

AT) are concatenated, they must be separated by a

;).

ERROR result code the balance of the command

200-character command buffer limit. (See

Parameters

Most AT commands support one or more parameters, usually
a number. Allowed values are specified in this reference.

Commands that normally accept a single numeric option
switch (
assume a value of zero (

[<n>]) and are issued without that parameter will

0).

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Modem Basics

Note: Entering incorrect syntax
or a parameter outside of the
specified range may have
unexpected results.

Defaults shown in the command tables are those for the
factory settings of the modem. They are not the defaults
assumed for a command issued without parameters, which are
noted in the text.

Registers

Some registers are read only. Attempting to write to them
yields an

Some registers store the setting of commands. Changing the
register is equivalent to changing the command setting.

The table for S registers indicates the standard default values.
The factory defaults are also noted in a separate sub-section.

ERROR result code.

Responses and Result Codes

Most commands return only a result code; however, some
commands request information, which is provided by the
modem as a response prior to the result code.

Possible result codes

Result codes are not shown in the command tables unless
special conditions apply. Generally the result code
returned when the command has been executed.
be returned if parameters are out of range, and will be
returned if the command is not recognized, or the command is
not permitted in the current mode, state, or condition of the
modem.

See the table on page 106 for a listing of result codes.

OK is

ERROR may

Human vs. machine interface

The AT command interface was designed for human inter­action. When an intelligent host is managing a modem, the
interface may need to be altered (result code words replaced
with numbers, for example). Framing characters (line feeds
and carriage returns) must be properly understood to ensure
the host system properly parses the responses and result
codes.

As shipped, the modem is configured with these settings:

• Echo enabled (E1) causes the modem to echo characters

received from the host back to it while in command state.
The backspace is echoed as
erase the last character.

<BS> <space> <BS> in order to

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MP 700 Series GPS AT Command Reference

• Quiet off (Q0) enables the modem to issue result codes

• Verbose result codes enabled (V1) provides results in

With Echo on (E1 - the default) data received from the local
host while in command state is echoed back to the host. This
can present problems to machine control, which is not inter­ested in an echo of its own commands to the modem. In some
configurations the echo should be turned off (

Response and Result Framing

Depending on the modem configuration, modem responses
and result codes are framed, typically with the
characters.

If you are designing or customizing software that will interface
with the modem using AT commands, it is necessary to under­stand how the modem frames its responses and result codes.

following commands. Quiet on (
codes entirely; responses remain unaffected.

English text appended with
returns the results as ASCII numeral codes. Numeric codes
are much easier to process using software.

Q1) suppresses result

<CR><LF>. Verbose off (V0)

E0).

<CR> and <LF>

Framing Characters The modem frames its replies with
carriage return and line feed characters as they are defined in
registers
value 13 for carriage return (
(The following discussion assumes that
used.)

S3 and S4 respectively. These are normally the ASCII

<CR>) and 10 for line feed (<LF>).

<CR> and <LF> are

Response framing

Regardless of how the modem is configured, responses to
commands are in the form of ASCII text with a trailing

<CR><LF>. Where a response has more than one line, each line

is terminated with a

When the Verbose setting is on (ATV1, see page 102) each
response has a leading
there are no leading characters prior to the first line of
response.

The setting of Quiet (ATQ, see page 102) has no impact on
responses.

<CR><LF>.

<CR><LF>. If Verbose is off (ATV0),

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Modem Basics

Result code framing

Every command will return a result code unless the Quiet
command is enabled. If Quiet is on (
neither framing characters nor result code is returned.

A leading <CR><LF> is inserted ahead of the result code if
Verbose is on (
leading characters prior to the ASCII numeral result. The result
code is always followed by a
only if Verbose is on. For example, the result code
as:

• <CR><LF>OK<CR><LF>

if verbose is on (ATV1)

• 0<CR>

if verbose is off (ATV0)

When ATV1 is set and there is an error,

<CR><LF>ERROR<CR><LF> is sent to the host computer and no

subsequent commands in the command line are processed. If

ATV0 is set, result code 4<CR> is sent instead.

ATV1, see page 102). Otherwise there are no

<CR>. There is a trailing <LF>

ATQ1, see page 102) then

OK appears

The ERROR (or 4) response may be replaced by +CME ERROR:

<err>

when the command is not processed because of a GSM

radio connection error.

GPS data format

The MP 700 Series GPS sends GPS data out in UDP packets.
The packets contain either:

• TAIP o r NMEA messages

• Data packets framed according to a Sierra Wireless

protocol called RNAP (Remote Network Access Protocol).

RNAP is described in detail in the Software Installation, Configu-
ration, and Integration Guide on the CD that is shipped with the
MP 750 GPS.

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MP 700 Series GPS AT Command Reference

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3: Command Reference

• Introduction

• Command Types

• Command Reference
Table

• Result Codes

• Factory Default
Settings

Introduction

As described in the previous section, AT commands are
available with Sierra Wireless GSM products for users of the
COM serial interface. The commands allow control of Circuit
Switched Data (CSD) calls and data exchange, similar to dial­up modems, but without wires, and with additional
commands available specific to GSM, GPRS, and EDGE.

The AT command set has grown from the original set used
with Hayes™ landline modems to support wireless connec­tions and is now standardized by the Third Generation
Partnership Project (3GPP). The commands are defined in the
standards known as V.25ter (for standard modem commands),
GSM 07.07 (for GSM and GPRS) and GSM 07.05 (for text
messaging, also known as short message service—SMS). The
following sections describe those commands.

AT commands conform by default to the Phase 2 specifications
for GSM 07.07 and GSM 07.05. Some AT commands have been
implemented according to Phase 2+ in order to support
extended features, such as 14.4 kbps CSD connections.

3

Note: Not every GSM/GPRS
product supports all commands.

Rev 3.2 Oct.05 23

The AT commands provide the following features for Sierra
Wireless GSM devices:

• Voice service

• Short Message Service (SMS)

• Circuit switched data service (CSD), including V.42bis data

compression

• GPRS packet data service

• EDGE packet data service

MP 700 Series GPS AT Command Reference

Command Types

Note: The AT prefix does not
appear in the reference tables. It
is, however, required and
assumed for all commands
unless specifically noted
otherwise.

The command reference table (beginning on page 31) details
the available AT commands in strict ASCII alphabetic order
(including character prefixes such as

!, & and +, which in ASCII

fall before the letters of the alphabet). Sections preceding those
tables outline how the commands are organized into
functional groups, including:

• Standard modem commands, beginning on page 24.

• GSM voice and circuit-switched data from page 26.

• SMS commands, page 27.

• GPRS packet data commands, page 28.

• EDGE packet data commands, page 28.

Within each functional section, commands also appear in
ASCII alphabetic order, with a cross-reference to the full
description in the reference table. This format allows quick
lookup of each command to verify syntax, parameters, and
behaviors.

Standard Modem Commands (V.25ter)

Sierra Wireless GSM/GPRS devices support most of the
standard AT commands used by telecommunications software
for over twenty years.

The following commands are derived from the original 1981
Hayes AT landline modem command set, with some
additional commands specific to wireless devices.

These commands have been standardized by the International
Telecommunications Union (ITU) as ITU-T recommendation
V.250 (also known as V.25ter). You can find more information
on the standard at

www.itu.int.

Table 3-3: Standard modem commands

Command Description p.

&C Data carrier detect (DCD) options 58
&D Data terminal ready (DTR) options 58
&F Reset modem to factory default 58
&V Display current modem configuration 58
&W Store user-defined profile 59
+DR V.42bis compression reporting 96

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Command Reference

Table 3-3: Standard modem commands (cont.)

Command Description p.

+DS V.42bis compression control 97
+GMI Modem manufacturer 97
+GMM Modem model 97
+GMR Current modem firmware version 97
+GOI Global object identification 97
+GSN Display IMEI 98
+IFC Local flow control 98
+IPR Fixed local data rate 98
A/ Reissue last AT command 100
A Answer incoming call (or GPRS network

ATD**## Make GPRS connection 100
E<n> Command echo mode 101
H[0] Hang up (disconnect) 101
I<n> Display product identification 101

L

(ignored)

M

(ignored)

O<n> Switch from command state to data state 102

P

(ignored)

Q<n> Quiet—suppress result codes 102

S0=<n>=<x>

S<n>?

T
(ignored)

request)

Set speaker loudness 101

Set speaker mode 101

Pulse dialing 102

Status Register Set/Query 104

Tone dialing 102

100

V<n> Verbose result code format 102
Z Reset modem to user-defined profile 103

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MP 700 Series GPS AT Command Reference

GSM Voice and Circuit-Switched Data
Commands (GSM 07.07)

These commands are specified in the GSM 07.07 standard and
control functions related to GSM voice, and CSD—similar to
those provided by many GSM mobile phones.

Table 3-4: GSM commands

Command Description p.

+CBST Select bearer service type 59
+CCFC Call forwarding number and conditions 60
+CCWA Call waiting control 61
+CEER Extended error report 62
+CGMI Request manufacturer identification 69
+CGMM Request model identification 69
+CGMR Request revision identification 69
+CGSN Display IMEI 72
+CIMI Request international mobile subscriber identity

(IMSI)

+CLCC List current calls 73
+CLCK Facility lock 74
+CLIP Calling line identification presentation 75
+CLIR Calling line identificatio n restriction 75
+CMEE Report mobile equipment error 76
+COPS Operator selectio n 84
+CPAS Modem activity status 86
+CPBF Find phonebook entries 86
+CPBR Read phonebook entries 87
+CPBS Phonebook memory storage 87
+CPBW Write phonebook entry 88
+CPIN Enter PIN 89
+CPWD Cha nge password 89

72

+CR Service reporting control 90
+CRC Cellular result codes for incoming calls 90

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Command Reference

Table 3-4: GSM commands

Command Description p.

+CREG GSM network registration 91
+CRLP Radio link protocol 92
+CSCS Character set 93
+CSTA Type of address 95
+CSQ Signal quality report 95
+VTD Tone duration 99
+VTS DTMF tone generation 99

SMS Commands (GSM 07.05)

The GSM 07.05 standard provides the following commands for
controlling text messaging, also known as Short Message
Service (SMS).

Table 3-5: SMS commands

Command Description p.

+CMGC Send SMS command 77
+CMGD Delete SMS message 77
+CMGF Select SMS message format 78
+CMGL List SMS messages 78
+CMGR Read SMS message 79
+CMGS Send SMS message 80
+CMGW Write SMS message to memory 81
+CMSS Send SMS message from storage 81
+CNMI New SMS message indications 82
+CRES Restore SMS settings 91
+CSAS Save SMS settings 92
+CSCA SMS service center address 93
+CSDH Show SMS text mode parameters 93
+CSMP Set SMS text mode parameters 93
+CSMS SMS message service 94

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MP 700 Series GPS AT Command Reference

GPRS Packet Data Commands
(GSM 07.07)

These commands, specified in the GSM 07.07 standard, control
General Packet Radio Service (GPRS) packet switched data
services.

Table 3-6: GPRS commands

Command Description p.

+CFUN Set phone functionality 62
+CGACT GPRS PDP context activation/deactivation 63
+CGATT GPRS attach or detach 63
+CGCLASS GPRS mobile station class 64
+CGDATA Enter data state 64
+CGDCONT Define Packet Data Protocol (PDP) context 65
+CGEREP Unsolicited GPRS event reporting control 68
+CGPADDR Show PDP address 70
+CGQMIN Set or query minimum acceptable quality of

+CGQREQ Request specified (or query current) quality of

+CGREG GPRS network registration status 72
+CGSMS Select service for SMS messages 72
+CNUM Retrieves the MSISDN from the SIM 83
+COPN Read operator names 84

service

service profile

EDGE Data Commands

These commands are only available on products that support
EDGE

Table 3-7: EDGE commands

Command Description p.

+CGEQMIN Set or Query Minimum Quality of Service Profile 66
+CGEQREQ Set or Query Requested Quality of Service

(Enhanced Data rates for Global Evolution).

Profile

70

71

68

+CTMSET Enable / disable support for CTM / TTY 96

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