Symbol CRD 1500 Manual

CRD 1500
Modem/Charging Cradle
Programmer’s Guide

2
72E-52775-01
Revision A — May 2001
Symbol Technologies, Inc. One Symbol Plaza, Holtsville N.Y. 11742
CRD 1500 Modem/Charging Cradle Programmer’s Guide

CRD 1500 Modem/Charging Cradle
Programmer’s Guide
72E-52775-01
Revision A
May 2001

ii
2001 by Symbol Technologies, Inc. All rights reserved.
No part of this publication may be reproduced or used in any form, or by any electrical or
mechanical means, without permission in writing from Symbol. This includes electronic or
mechanical means, such as photocopying, recording, or information storage and retrieval
systems. The material in this manual is subject to change without notice.
The software is provided strictly on an “as is” basis. All software, including firmware,
furnished to the user is on a licensed basis. Symbol grants to the user a non-transferable
and non-exclusive license to use each software or firmware program delivered hereunder
(licensed program). Except as noted below, such license may not be assigned,
sublicensed, or otherwise transferred by the user without prior written consent of Symbol.
Noright to copyalicensed program inwhole or in part is granted, except as permitted under
copyright law. The user shall not modify, merge, or incorporate any form or portion of a
licensed program with other program material, create a derivative work from a licensed
program, or use a licensed program in a network without written permission from Symbol.
The user agrees to maintain Symbol’s copyright notice on the licensed programs delivered
hereunder, and to include the same on any authorized copies it makes, in whole or in part.
The user agrees not to decompile, disassemble, decode, or reverse engineer any licensed
program delivered to the user or any portion thereof.
Symbol reserves the right to make changes to any software or product to improve reliability,
function, or design.
Symbol does not assume any product liability arising out of, or in connection with, the
application or use of any product, circuit, or application described herein.
No license is granted, either expressly or by implication, estoppel, or otherwise under any
Symbol Technologies, Inc., intellectual property rights. An implied license only exists for
equipment, circuits, and subsystems contained in Symbol products.
Symbol is a registeredtrademarksofSymbol Technologies, Inc.InetisatrademarkofINET,
Inc. Other product names mentioned in this document may be trademarks or registered
trademarks of their respective companies and are hereby acknowledged.
Symbol Technologies, Inc.
One Symbol Plaza
Holtsville, N.Y. 11742-1300
WWW: http://www.symbol.com

iii
Contents
About This Guide
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
Notational Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
Service Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii
Symbol Support Centers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .viii
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xi
Warranty Coverage and Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xi
General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xi
Chapter 1. AT Command Set
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
AT Commands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
A/, Re-execute Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
AT= x, Write to Selected S-Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
AT?, Read Selected S-Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
A, Answer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Bn, CCITT or Bell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Cn, Carrier Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
En, Command Echo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Fn, Select Line Modulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Hn, Disconnect (Hang-Up) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
P, Set Pulse Dial Default . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
Sn, Read/Write S-Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
T, Set Tone Dial Default. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
Vn, Result Code Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
Xn, Extended Result Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
Zn, Soft Reset and Restore Profile. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16
AT& Commands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17
&Dn, DTR Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17
&Fn, Restore Factory Configuration (Profile) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-18

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CRD 1500 Modem/Charging Cradle Programmer’s Guide
&Gn, Select Guard Tone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-18
&Mn, Asynchronous/Synchronous Mode Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-19
&Rn, RTS/CTS Option. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-21
&Tn, Test and Diagnostics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-21
&Wn, Store Current Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-24
&Yn, Designate a Default Reset Profile. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-25
&Zn=x, Store Telephone Number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-25
AT% Commands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-26
%C, Enable/Disable Data Compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-26
%En - Enable/Disable Line Quality Monitor and Auto-Retrain or Fallback/Fall Forward. . . .1-26
%L, Line Signal Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-27
%Q, Line Signal Quality. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-27
AT\ Commands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-28
\An, Select Maximum MNP Block Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-28
\Bn, Transmit Break to Remote . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-28
\Kn, Break Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-29
AT+ Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-33
+GCI, Country Profiles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-33
+MS, Select Modulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-34
Chapter 2. S-Registers
Factory Defaults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
S-Register Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4
S0, Number of Rings to Auto-Answer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
S1, Ring Counter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4
S3, Carriage Return Character . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
S4, Line Feed Character . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
S6, Wait Time for Dial Tone Before Blind Dialing, or After “W” Dial Modifier. . . . . . . . . . . . . . 2-6
S8, Pause Time For Dial Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7
S9, Carrier Detect Response Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7
S10, Lost Carrier To Hang Up Delay. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-8
S12, Escape Prompt Delay (EPD). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
S13, Check Line Quiet before Line Seize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-8
S14, General Bit Mapped Options Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-9
S15, Reserved. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-9
S16, General Bit Mapped Test Options Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-10
S17, Reserved. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-10
S18, Test Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
S19, AutoSync Bit Mapped Options. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-11
S20, AutoSync HDLC Address or BSC Sync Character . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-12
S21, V.24/General Bit Mapped Options Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-12
S22, Speaker/Results Bit Mapped Options Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-13
S25, Delay To DTR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-15

v
Contents
S26, RTS to CTS Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15
S28, Bit Mapped Options Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
S30, Disconnect Inactivity Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
S31, Bit Mapped Options Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
S32, XON Character. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
S33, XOFF Character. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
S34-S35, Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
S36, LAPM Failure Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
S37, Desired Line Connection Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
S38, Delay Before Forced Hang Up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-20
S40, General Bit Mapped Options Status. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-21
S41, General Bit Mapped Options Status. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-22
S48, V.42 Negotiation Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23
S82, Break Handling Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23
S86, Call Failure Reason Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-24
S95, Extended Result Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-24
Index
Feedback

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CRD 1500 Modem/Charging Cradle Programmer’s Guide

vii
About This Guide
Introduction
The CRD 1500 Modem/Charging Cradle Programmer’s Guide provides information
necessary for developing applications for the SPT 1500/1550 using the SPT 1500 Modem/
Charging Cradle.
Notational Conventions
This document uses these conventions:
• “terminal” refers to both the SPT 1500 and SPT 1550.
• “User” refers to anyone using an application on the SPT 1500 or SPT 1550.
• “You” refers to the developer or other person using this manual as a reference to
develop applications for the SPT 1500 or SPT 1550.
• Italics are used to highlight specific items in the general text, and to identify
chapters and sections in this and related documents. It also identifies names of
dialog boxes and tabs within dialog boxes.
• Bullets (•) indicate:
• lists of alternatives or action items.
• lists of required steps that are not necessarily sequential.
• Numbered lists indicate a set of sequential steps, i.e., those that describe step-by-
step procedures.

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CRD 1500 Modem/Charging Cradle Programmer’s Guide
Service Information
If you have a problem with your equipment, contact the Symbol Support Center. If your
problem cannot be resolved over the phone, you may need to return your equipment for
servicing. If that is necessary, you will be given special directions.
Note:Symbol Technologies is not responsible for any damages incurred
during shipment if the approved shipping container is not used.
Shipping the units improperly can possibly void the warranty. If the
original shipping container has not been kept, contact Symbol to
have another sent to you.
Symbol Support Centers
For service information, warranty information or technical assistance contact or call the
Symbol Support Center in:
United States
Symbol Technologies, Inc.
One Symbol Plaza
Holtsville, New York 11742-1300
1-800-659-2240
Canada
Symbol Technologies Canada, Inc.
2540 Matheson Boulevard East
Mississauga, Ontario, Canada L4W 4Z2
905-629-7226
United Kingdom
Symbol Technologies
Symbol Place
Winnersh Triangle, Berkshire RG41 5TP
United Kingdom
0800 328 2424 (Inside UK)
[phone] (Outside UK)
Asia/Pacific
Symbol Technologies Asia, Inc.
230 Victoria Street #04-05
Bugis Junction Office Tower
Singapore 188024
337-6588 (Inside Singapore)
[phone] (Outside Singapore)

ix
About This Guide
Australia
Symbol Technologies Pty. Ltd.
432 St. Kilda Road
Melbourne, Victoria 3004
1-800-672-906 (Inside Australia)
[phone] (Outside Australia)
Austria
Symbol Technologies Austria GmbH
Prinz-Eugen Strasse 70
Suite 3
2.Haus, 5.Stock
1040 Vienna, Austria
1-505-5794 (Inside Austria)
[phone] (Outside Austria)
Denmark
Symbol Technologies AS
Gydevang 2,
DK-3450 Allerod, Denmark
7020-1718 (Inside Denmark)
[phone] (Outside Denmark)
Europe/Mid-East Distributor Operations
Contact your local distributor or call
[phone]
Finland
Oy Symbol Technologies
Kaupintie 8 A 6
FIN-00440 Helsinki, Finland
9 5407 580 (Inside Finland)
[phone] (Outside Finland)
France
Symbol Technologies France
Centre d'Affaire d'Antony
3 Rue de la Renaissance
92184 Antony Cedex, France
01-40-96-52-21 (Inside France)
[phone] (Outside France)
Germany
Symbol Technologies GmbH
Waldstrasse 68
D-63128 Dietzenbach, Germany
6074-49020 (Inside Germany)
[phone] (Outside Germany)
Italy
Symbol Technologies Italia S.R.L.
Via Cristoforo Columbo, 49
20090 Trezzano S/N Navigilo
Milano, Italy
2-484441 (Inside Italy)
[phone] (Outside Italy)

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CRD 1500 Modem/Charging Cradle Programmer’s Guide
If you purchased your Symbol product from a Symbol Business Partner, contact that
Business Partner for service.
Latin America Sales Support
7900 Glades Road
Suite 340
Boca Raton, Florida 33434 USA
1-800-347-0178 (Inside United States)
[phone] (Outside United States)
Mexico
Symbol Technologies Mexico Ltd.
Torre Picasso
Boulevard Manuel Avila Camacho No 88
Lomas de Chapultepec CP 11000
Mexico City, DF, Mexico
5-520-1835 (Inside Mexico)
[phone] (Outside Mexico)
Netherlands
Symbol Technologies
Kerkplein 2, 7051 CX
Postbus 24 7050 AA
Varsseveld, Netherlands
315-271700 (Inside Netherlands)
[phone] (Outside Netherlands)
Norway
Symbol Technologies
Trollasveien 36
Postboks 72
1414 Trollasen, Norway
66810600 (Inside Norway)
[phone] (Outside Norway)
South Africa
Symbol Technologies Africa Inc.
Block B2
Rutherford Estate
1 Scott Street
Waverly 2090 Johannesburg
Republic of South Africa
11-4405668 (Inside South Africa)
[phone] (Outside South Africa)
Spain
Symbol Technologies S.A.
Edificioi la Piovera Azul
C. Peonias, No. 2 - Sexta Planta
28042 Madrid, Spain
9-1-320-39-09 (Inside Spain)
[phone] (Outside Spain)
Sweden
Symbol Technologies AB
Albygatan 109D
Solna
Sweden
84452900 (Inside Sweden)
[phone] (Outside Sweden)

xi
About This Guide
Warranty
Symbol Technologies, Inc (“Symbol”) manufactures its hardware products in accordance with
industry-standard practices. Symbol warrants that for a period of twelve (12) months from date of
shipment, products will be free from defects in materials and workmanship.
This warranty is provided to the original owner only and is not transferable to any third party. It shall
not apply to any product (i) which has been repaired or altered unless done or approved by Symbol,
(ii) which has not been maintained in accordance with any operating or handling instructions supplied
by Symbol, (iii) which has been subjected to unusual physical or electrical stress, misuse, abuse,
power shortage, negligence or accident or (iv) which has been used other than in accordance with
the product operating and handling instructions. Preventive maintenance is the responsibility of
customer and is not covered under this warranty.
Wear items andaccessories having a Symbol serial number, will carry a 90-day limited warranty. Non-
serialized items will carry a 30-day limited warranty.
Warranty Coverage and Procedure
During the warranty period, Symbol will repair or replace defective products returned to Symbol’s
manufacturing plant in theUS. For warrantyservice in NorthAmerica, call the Symbol Support Center
at 1-800-653-5350. International customers should contact the local Symbol office or support center.
If warranty service is required, Symbol will issue a Return Material Authorization Number. Products
must be shipped in the original or comparable packaging, shipping and insurance charges prepaid.
Symbol will ship the repaired or replacement product freight and insurance prepaid in North America.
Shipments from the US or other locations will be made F.O.B. Symbol’s manufacturing plant.
Symbol will use new or refurbished parts at its discretion and will own all parts removed from repaired
products. Customer will pay for the replacement product in case it does not return the replaced
product to Symbol within 3 days of receipt of the replacement product. The process for return and
customer’s charges will be in accordance with Symbol’s Exchange Policy in effect at the time of the
exchange.
Customer accepts full responsibility for its software and data including the appropriate backup
thereof.
Repair or replacement of a product during warranty will not extend the original warranty term.
Symbol’s Customer Service organization offers an array of service plans, such as on-site, depot, or
phone support, that can be implemented to meet customer’s special operational requirements and
are available at a substantial discount during warranty period.
General
Except for the warranties stated above, Symbol disclaims all warranties, express or implied, on
products furnished hereunder, including without limitation implied warranties of merchantability and
fitnessfor a particular purpose. The stated expresswarranties are inlieu of all obligations or liabilities
on part of Symbol for damages, including without limitation, special, indirect, or consequential
damages arising out of or in connection with the use or performance of the product.

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CRD 1500 Modem/Charging Cradle Programmer’s Guide
Seller’s liability for damages to buyer or others resulting from the use of any product, shall in no way
exceed the purchase price of said product, except in instances of injury to persons or property.
Some states (or jurisdictions) do not allow the exclusion or limitation of incidental or consequential
damages, so the proceeding exclusion or limitation may not apply to you.

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Chapter 1
AT Command Set
Introduction
The Symbol MCDA Modem Card is used internally within the CRD1500-1000MC and
CRD1500-1000EU.
The 14.400kbps (V32bis) modem has additional Data Compression (MNP5, V42bis) for
faster throughput to take advantage of the higher serial port speeds to the SPT1500. Error
Correction (MNP4, V42) is also included.
This chapter describes AT commands for the modem, along with parameters applicable to
each command. The defaults for each configuration command are those used in the factory
profile 0.

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CRD 1500 Modem/Charging Cradle Programmer’s Guide
AT Commands
A/, Re-execute Command
Description
The modem behaves as if the DTE has re-sent the last command line. “A/” repeats all
commands in the command buffer.
This command re-executes a call (using the Dial command) that failed to connect due to a
busy line, no answer, or a wrong number, and must appear alone on a command line. Do
not terminate with a carriage return.
AT= x, Write to Selected S-Register
Description
Writes the value x to the currently selected S-Register. Use the ATSn command to select
an S-Register. All S-Registers return OK if xis a number. Some registers may not be written
due to country-specific PTT limitations.
Result Codes
OK For all arguments
AT?, Read Selected S-Register
Description
Reads and displays the selected S-Register. Use the ATSn command to select an S-
Register.
Result Codes
OK For all arguments
A, Answer
Description
The modem goes off-hook and attempts to answer an incoming call if proper conditions are
met. When answer handshake is complete, the modem goes on-line in answer mode.

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AT Command Set
Bn, CCITT or Bell
Description
When configured to allow either option, the modem selects Bell or CCITT modulation for a
line speed connection of 300 or 1200 bps according to the parameter supplied. Any other
line speed uses a CCITT modulation standard. The parameter value, if valid, is written to
S27 bit 6. (See Fn, Select Line Modulation on page 1-6.)
B0 Selects CCITT operation at 300 or 1200 bps during Call Establishment and a
subsequent connection.
B1 Selects BELL operation at 300 or 1200 bps during Call Establishment and a
subsequent connection.
Result Codes
OK n= 0 or 1
ERROR Otherwise
Cn, Carrier Control
Description
Included for compatibility only,andhas no effect other thanreturninga result code. Theonly
valid parameter is 1.
Result Codes
OK n = 1
ERROR Otherwise

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CRD 1500 Modem/Charging Cradle Programmer’s Guide
Dn, Dial
Description
Directs the modem to go on-line, dial according to the string entered, and attempt to
establish a connection. If no dial string is supplied, the modem goes on-line and attempts
the handshake in originate mode.
Note
If the ATD command is issued before the S1 register clears, the modem responds with the
NO CARRIER result code.
Dial Modifiers
Valid dial string parameters follow. Punctuation characters may be used for clarity;
parentheses, hyphen, and spaces are ignored.
0-9 DTMF digits 0 to 9.
* The 'star' digit (tone dialing only).
# The 'gate' digit (tone dialing only).
A-D DTMF digits A, B, C, and D.
LRe-dial last number: the modem re-dials the last valid telephone number.
The L appears immediately after the D; characters that follow are ignored.
PSelect pulse dialing: pulse dial the numbers that follow until “T” is
encountered. Affects currentand subsequent dialing.Pulse dialing is not fitted
on standard European model CRD1500-100M-01.
TSelect tone dialing:tonedial the numbersthat follow until“P”isencountered.
Affects current and subsequent dialing.
R This command is accepted but not acted on.
S=n Dial the number stored in the directory (n = 0 to 3) (see &Zn=x, Store
Telephone Number on page 1-25).
WWait for dial tone: the modem waits for a dial tone before dialing the digits
following “W”. If a dial tone is not detected within the time specified by S6, the
modem aborts the sequence, returns on-hook, and generates an error
message.

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AT Command Set
@Wait for silence: the modem waits for at least 5 seconds of silence in the call
progress frequency band beforecontinuing withthe nextdialstringparameter.
If the modem does not detect the silence before the expiration of the call abort
timer (S7), the modem terminates the call attempt with a NO ANSWER
message. If busy detection is enabled, the modem may terminate the call with
the BUSY result code. If an answer tone arrives during execution of this
parameter, the modem handshakes.
,Dial pause: the modem pauses for a time specified by S8 before dialing the
digits following “,”.
;Return to command state: Added to the end of a dial string, returns the
modem to the command state after processing the portion of the dial string
preceding the “;”. This allows you to issue additional AT commands while
remaining off-hook. Place these commands in the original command line
following the “;” and/or on subsequent command lines. The modem enters call
progress only after an additional dial command is issued without the “;”
terminator. Use “H” to abort the dial in progress, and go back on-hook.
( ) Ignored: may be used to format the dial string.
-Ignored: may be used to format the dial string.
<space> Ignored: may be used to format the dial string.
<i> Invalid character: ignored.
En, Command Echo
Description
Enables or disables the echo of characters to the DTE according to the parameter supplied.
The parameter value, if valid, is written to S14 bit 1.
E0 Disables command echo
E1 Enables command echo (default)
Result Codes
OK n= 0 or 1
ERROR Otherwise

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CRD 1500 Modem/Charging Cradle Programmer’s Guide
Fn, Select Line Modulation
Description
Selects the line modulation according to the parameter supplied. The line modulation is
fixed unless Automode is selected. This command interacts with the S37 and the N
command. The parameter value, if valid, is written to S37 bits 0-4.
To select line modulation, we recommend that either the F command, or a combination of
the S37 and the N command be used, but not both.
F0 Selects auto-detect mode. Sets N1 and sets S31 bit 1. In this mode, the
modem configures for automode operation. All connect speeds supported by
the modem are possible according to the remote modem's preference. The
contents of S37 are ignored, as well as the sensed DTE speed.
F1 Selects V.21 or Bell 103 according to the B setting as the only acceptable line
speed resulting in a subsequent connection. Sets N0, sets S37 to 1, and
clears S31 bit 1. This command is equivalent to command string ATN0S37=1.
F2 Not supported.
F3 Selects V.23 as the only acceptable line modulation for a subsequent
connection. Originator is at 75 bps and answerer is at 1200 bps. Sets N0, sets
S37 to 7, and clears S31 bit 1. This command is equivalent to command string
ATN0S37=7.
F4 Selects V.22 1200 or Bell 212A according to the B command setting as the
only acceptable line speed for a subsequent connection. Sets N0, sets S37 to
5, and clears S31 bit 1. This command is equivalent to command string
ATN0S37=5.
F5 Selects V.22 bis as the only acceptable line modulation for a subsequent
connection. Sets N0, sets S37 to 6, and clears S31 bit 1. This command is
equivalent to command string ATN0S37=6.
F6 Select V.32 bis 4800 or V.32 4800 as the only acceptable line modulation for
a subsequent connection. Sets N0, sets S37 to 8, and clears S31 bit 1. This
command is equivalent to command string ATN0S37=8.
F7 Selects V.32 bis 7200 as the only acceptable line modulation for a subsequent
connection. Sets N0, sets S37 to 12, and clears S31 bit 1. This command is
equivalent to command string ATN0S37=12. This setting also allows