Telenetics Global Carrier 56 User manual

Global Carrier 56 Modem
User’s Guide
0049-2200-001 Rev.A

Page ii
The products and programs described in this User’s Guide are licensed products of Telenetics
Corporation. This User’s Guide contains proprietary information protected by copyright, and
this User’s Guide and all accompanying hardware and documentation are copyrighted.
Telenetics Corporation does not warrant that the hardware will work properly in all
environments and applications, and makes no warranty and representation, either implied or
expressed, with respect to the quality, performance, merchantability, or fitness for a particular
purpose.
Information in this User’s Guide is subject to change without notice and does not represent a
commitment on the part of Telenetics Corporation. Telenetics Corporation assumes no
responsibility for any inaccuracies that may be contained in this User’s Guide.
Telenetics Corporation makes no commitment to update or keep current the information in
this User’s Guide, and reserves the right to make changes to this User’s Guide and/or product
without notice.
No part of this manual may be reproduced or transmitted in any form or by any means,
electronic or mechanical, including photocopying, recording, or information storage and
retrieval systems, for any purpose other than the purchaser’s personal use, without the
express written permission of Telenetics Corporation.
Copyright 2002 Telenetics Corporation.
25111 Arctic Ocean
Lake Forest, California 92630
Tel: [phone]
Fax: [phone]
Web site: www.telenetics.com

Page iii
Contact Information
Please contact Telenetics for help, information, sales inquiries, or to join the Telenetics Mailing
List.
Technical Support
e-mail: [email protected]
WebPage: http://www.telenetics.com
Phone: [phone]
Fax: [phone]
Mailing List
For the latest sales and technical information, subscribe to the Telenetics Mailing List by sending
an e-mail to:
[email protected]

Page iv
Contents
Introduction ....................................................................................................................................8
Installation ......................................................................................................................................9
Unpacking Your Hardware .....................................................................................................9
Additional Items You Need ......................................................................................................9
Hardware Overview.............................................................................................................10
InstallationSummary ............................................................................................................. 11
Connecting the Cables..........................................................................................................12
Driver Installation...................................................................................................................13
...............................................................................................................................................13
ModemLEDDisplay...............................................................................................................14
FrontPanel Mode LEDs.........................................................................................................15
TheATCommands ................................................................................................................16
Selecting Speeds ..................................................................................................................22
Flow Control ..........................................................................................................................26
Configuring the Modem .........................................................................................................28
Error Correction...........................................................................................................................29
Error Correction Protocols ....................................................................................................29
Security & Encryption..................................................................................................................34
Encryption .............................................................................................................................41
Synchronous Modes ...................................................................................................................49
Leased Line Operations .......................................................................................................53
DumbMode Operation .................................................................................................................56
The Option Switches ............................................................................................................62
V.25bis Operations......................................................................................................................63
Distinctive Ring ............................................................................................................................71
CallerID ........................................................................................................................................72
CallLogging ...........................................................................................................................75
Commands ...................................................................................................................................76
+++ Escape Sequence .........................................................................................................76
**** Remote Access Sequence ............................................................................................77
AT? Interactive Command Help .............................................................................................79
A/ Repeat Last Command .....................................................................................................80
ATA Answer..........................................................................................................................81
ATBn Select Communications Standard ...............................................................................82
ATD Dial .................................................................................................................................86
Dial Modifiers .........................................................................................................................87
ATE Echo ...............................................................................................................................92
ATH Hang Up .........................................................................................................................93
ATI Identity .............................................................................................................................94
ATL Speaker Volume Control ................................................................................................95
ATMMonitor ..........................................................................................................................96
ATO Return to On-line State..................................................................................................97
ATQ Quiet (Suppress Response Codes).............................................................................99
ATR Set Terminal Speed......................................................................................................100
ATSn? Display S Register Value ........................................................................................102
ATSn= Set S Register Value ...............................................................................................103
ATV Verbal Response Codes.............................................................................................104
ATW Connection Speed Information ...................................................................................105

Page v
ATX Extended Response Codes ........................................................................................106
ATZn Restore Configuration Profile....................................................................................108
AT&B Character Length......................................................................................................109
AT&C Controlling Data Carrier Detect ................................................................................. 110
AT&DControlling Data Terminal Ready ............................................................................... 111
AT&F.Reinitialise Modem .................................................................................................... 112
AT&F Restore Factory Defaults ......................................................................................... 113
AT&G Guard Tone ............................................................................................................... 114
AT&HClock Control ............................................................................................................. 115
AT&K Flow Control..............................................................................................................116
AT&L Leased Line............................................................................................................... 118
AT&M Synchronous/Asynchronous Mode ........................................................................ 119
AT&N Abort Connection ......................................................................................................121
AT&RRTS/CTSControl .......................................................................................................122
AT&SControlling DSR .........................................................................................................123
AT&Vn View Active Configuration Profile ..........................................................................124
AT&Wn Write Configuration Parameters ............................................................................125
AT&X Transmit Clock...........................................................................................................126
AT&Yn Select Stored Profile on Power Up ........................................................................127
AT&Z Stored Phone Number ...............................................................................................128
AT#A Universal Remote Access ........................................................................................129
AT#B 1200bps Originate Mode ...........................................................................................131
AT#C V.25 Calling Tones.....................................................................................................132
AT#CIDCallerID ..................................................................................................................133
AT#D V.25bis Direct Calling ................................................................................................135
AT#E Encryption..................................................................................................................136
AT#HDisplay Help...............................................................................................................137
AT#I V.22bis Leased Line ...................................................................................................138
AT#J V.42 Capability Checking ...........................................................................................139
AT#KMNP10 mode.............................................................................................................140
AT#MCommand Mode Selection ........................................................................................141
AT#N V.25bis Character Encoding .....................................................................................142
AT#O Buffer Overflow .......................................................................................................143
AT#Q V.25bis Terminal Speed.............................................................................................144
AT#REnable Remote Control ..............................................................................................145
AT#S Security Menu ...........................................................................................................146
AT#U V.25bis Character Set...............................................................................................147
AT#V Verifier ......................................................................................................................148
AT%B AutoAnswer Setting ................................................................................................149
AT%C Compression Control ...............................................................................................150
AT%D Set Disconnect Delay ..............................................................................................151
AT%EAutoEQM Retrain .....................................................................................................152
AT%FDTR/DSR override ....................................................................................................153
AT%HMNP10 Negotiation Speed.......................................................................................154
AT%K CTS During Dial and Handshake..............................................................................155
AT%L Display Line Signal Level .........................................................................................156
AT%Ln Transmit Level (Data Mode)...................................................................................157
AT%MMode LED Indication ................................................................................................158
AT%N Non-Standard Terminal Speeds ...............................................................................159
AT%PCONNECTMessageTiming ......................................................................................160
AT%Q Line Signal Quality ...................................................................................................161
AT%R CTS Override ...........................................................................................................162
AT%S DSR Override ...........................................................................................................163

Page vi
AT%T DCD Override ...........................................................................................................164
AT%U V.42 Response Codes.............................................................................................165
AT%W Welcome Message .................................................................................................166
AT\AMNP Block Size...........................................................................................................167
AT\Bn Generate Break ........................................................................................................168
AT\JAuto-Reliable Fallback.................................................................................................169
AT\K Break Control..............................................................................................................170
AT\N Asynchronous Operating Mode.................................................................................172
AT\Q Extended Flow Control ..............................................................................................174
AT\S Display Active Configuration......................................................................................175
AT\Tn Inactivity Timer (Data Mode).....................................................................................176
AT\V Error Correction Response Codes ............................................................................177
AT\X XON/XOFF Pass Through ..........................................................................................178
AT*K Select Primary DES KEY from Stored Keys ..............................................................179
AT*RV.13 RemoteRTSSignalling ......................................................................................180
AT*S Change Current User Password...............................................................................181
AT*TAuto Call Redial...........................................................................................................182
AT*V Maximum V.42bis Dictionary Size .............................................................................183
AT*W Welcome Message Text............................................................................................184
AT*Y Escape Seq. Detection in Sync.................................................................................185
AT+ICF Character Framing and Parity Select .....................................................................186
AT+MSSelect Modulation ...................................................................................................187
AT+MS=? Reporting Supports Options...............................................................................191
AT-Q MNP10 Fallback to V.22bis ........................................................................................192
AT-DATETime& Date ..........................................................................................................193
AT-LOGCall Log..................................................................................................................194
AT:E V.32 compromise Equaliser ........................................................................................195
V.25BIS- CICConnect Incoming Call ..................................................................................196
V.25BIS- CRNDial ..............................................................................................................197
V.25BIS - CRS Dial Stored Number .....................................................................................199
V.25BIS- DICDisregard Incoming Call................................................................................200
V.25BIS - PRN StoredPhone Number .................................................................................201
V.25BIS - RST Reset ...........................................................................................................202
S Registers ................................................................................................................................203
ATS0 Rings Before Answer ...............................................................................................205
ATS1 Ring Count .................................................................................................................206
ATS2 Escape Sequence Character ...................................................................................207
ATS3 Carriage Return Character .......................................................................................208
ATS4 Line Feed Character .................................................................................................209
ATS5 Backspace Character ...............................................................................................210
ATS6 Dial Tone Wait Time ................................................................................................... 211
ATS7 Wait for Carrier .........................................................................................................212
ATS8 Pause Dial Modifier Delay .........................................................................................213
ATS9 Carrier Detect Response Time..................................................................................214
ATS10 Lost Carrier/Hang Up Delay ....................................................................................215
ATS11DTMFToneTiming ....................................................................................................216
ATS12 Escape Sequence Guard Time ...............................................................................217
ATS16 Test in Progress (read only) ...................................................................................218
ATS18 Test Timer ................................................................................................................219
ATS25 DTR Loss Detection ................................................................................................220
ATS26RTS/CTSDelay ........................................................................................................221
ATS27 Delay Before Dial ....................................................................................................222
ATS29 Hook Flash Duration ................................................................................................223

Page vii
ATS30 Inactivity Timer ........................................................................................................224
ATS33 EQM Threshold Value..............................................................................................226
ATS38 Disconnect Delay ....................................................................................................227
ATS42 Modem Disconnect Reason ....................................................................................228
ATS43 Break Sequence Length .........................................................................................229
ATS45 V.22bis EQM Threshold Value ................................................................................230
ATS57 DTR HighDetection .................................................................................................231
ATS62 V.42 Detection Timer ...............................................................................................232
ATS66 Remote Access Guard Time ...................................................................................233
ATS67 Remote Access Character .....................................................................................234
ATS69 Command LineTime-out..........................................................................................235
ATS71 Ignore IncomingCall ................................................................................................236
ATS74 Disconnect Reason for Prev. Call...........................................................................237
ATS80 Flow Control High Water Mark ................................................................................238
ATS81 Flow Control Low Water Mark................................................................................239
ATS82 Failsafe Flow Control Overrun ...............................................................................240
ATS95 Extended Response Codes ....................................................................................241
ATS96 Help Page Width ......................................................................................................242
ATS97 Help Page Length ....................................................................................................243
ATS105 Voice ‘Dead Man’Timer .........................................................................................244
ATS122 AutoRateChange ...................................................................................................245
ATS123 AutoRateChange ...................................................................................................246
ATS124 DurationEQM ........................................................................................................247
Modem Response Codes ..........................................................................................................248
RS-232 Signals ..........................................................................................................................250
Abbreviated Command List .......................................................................................................253
Glossary ....................................................................................................................................263
Specifications ............................................................................................................................284

Page 8
Introduction
Welcome to the Global Carrier 56 User Guide, a comprehensive guide to the efficient use of your
modem. Together with the Read Me First Guide supplied with your modem, this reference
manual provides all the information needed to make maximum use of your equipment and
software. The Global Carrier 56 User Guide is divided into the following sections:
Getting Started
❏A complete description about how to get started using your equipment, including basic
details and more advanced topics.
Error Correction
❏Examines and explains the error correction features, includingV.42bis data
compression, of your equipment.
Security
❏Examines and explains the data security and encryption features of your equipment.
Synchronous Modes
❏Full details on how to use your modem for synchronous operations.
Dumb Mode
❏Provides product specified information on Dumb Mode operation.
V.25bis Operations
❏Describes how your modem implements V.25bis and how it interacts with AT
commands.
Distinctive Ring
❏Explains how to use Distinctive Ring and its associated commands.
Caller Id
❏Explains how to use Caller Id and its associated commands.
AT Commands
❏Provides a complete description of all commands available in your modem.
S Registers
❏Introduces you to S Registers and how to use them.
❏Contains a description of the available S Registers.
Response Codes
❏This section provides information on the response codes supported by your modem.
RS-232 Signals
❏This section provides information on signals supported on the modem’s RS- 232
socket.
Abbreviated Command Listing
❏This section provides a quick reference of the commands for the Global Carrier 56.
Glossary of Communications Terms
❏Provides descriptions of modem, facsimile and other communications terms.

Installation
Page 9
Installation
Unpacking Your Hardware
Your package should include:
• The Global Carrier 56 modem
• An RJ-11 telephone-line cable
• A power supply module
• A DTE DB25 data cable
• This User’s Guide
If your package contents are damaged or missing, please contact your place of
purchase immediately.
Additional Items You Need
To use your mode, you need the following additional items:
• Two- or four-wire transmission line or leased line
• A power source that provides 85 to 265 Volts AC, 50 to 60 Hz, single phase

Page 10
Telco/Dial Line
Telephone
Set DTE RS232
Connector LowVoltage
PowerInput
ON/OFF
Hardware Overview
Back View
The following figure shows the back view of the Global Carrier 56 modem. Starting from
the left side, this view shows:
• A line jack for connecting the modem to the communications line.
• An audio jack for leased-line operation.
• Afemale, 25-pin RS-232 connector for connecting a standard DTE (RTU).
• A power connector.
• An ON/OFF switch.
Front View
The front view of the modem has 10 LED status indicators. For more information about
these indicators, see “Modem LED Display” on page 14 and “Front Panel Mode LEDs”
on page 15.
LEDs (see page 15)
Option DIP Switch
(see page 62)
Data/Talk Switch
(see page 58)
Mode Switch for
Dumb Operation
(see page 56)

Installation
Page 11
Installation Summary
The modem installation involves the following steps:
1. Finding a suitable location for the modem. See the section below.
2. Making the necessary modem connections. See page 12.
3. Installing the modem driver. See page 13.
Finding a Suitable Location
The location you select for your modem should provide easy access to the back panel
communications interfaces and provide a clear view of the front panel LED indicators.

Page 12
Connecting the Cables
1. Turn off your computer.
2. Plug the data cable's male end (pins showing) into the connector marked RS232 at the back
of your Modem and then plug the female end (no pins showing) of the same cable into the
COM port at the back of your computer.
3. Your computer's COM port could be 9 pins or 25 pins. Use the appropriate connector on
the cable suppled to conntect your Modem to your Serial port.
4. Plug the telephone cable into the connector marked LINE at the back of your Modem and
the other end of the cable into your telephone wall socket.
☞☞
☞☞
☞
Your Modem has a Telephone Set connector to allow 4-wire leased-line operation.
Refer to the section on Leased Line Operations for details on this feature.
5. Plug the power cable pin into the POWER connector at the back of your Modem and plug
the power supply into a suitable power point.
6. Use the ON/OFF switch to turn on your Modem. Then check that some of the Modem
lightsilluminate.
7. Restart your computer.
8. Now you need to install your Modem's Driver. Which operating system is your computer
running? Read the next section for driver installation instructions.
Telco/Dial Line
Telephone
Set DTE RS232
Connector LowVoltage
PowerInput
ON/OFF

Installation
Page 13
Windows 98
1. Please insert the driver CD supplied and, when the "Found New Hardware Wizard"
recognises the new Modem, click Next to search for the driver.
2. Select the "Search for the best driver your device. [Recommended]" and click "Next" to
continue.
3. Select the "Specify a location" option and type "D:\" where D:\ is the letter of your CD
ROM drive. Click "Next" to start the search for your driver.
4. Click "Next" to start the installation.
5. Click "Finish".
Windows 2000
Driver Installation
1. Windows will detect the modem automatically. Please insert the Telenetics CD supplied and
click "Next".
2. Select "Search for a suitable driver for my device [recommended]", and then click "Next".
3. Select "Specify a location" and click "Next".
4. Enter the driver location "D:\" where D:\ is the letter of your CD ROM drive and click on
"OK".
5. Windows will find the correct driver for your modem. Click "Next" to continue.
6. When the "Digital Signature Not Found" screen appears, click "Yes" to continue.
7. Click "Finish" to end this procedure.
Windows ME
1. Please insert the Telenetics CD supplied and, when the "Found New Hardware Wizard"
recognises the new Modem, select "Specify the location of the driver [Advanced]" and click
"Next" to search for the driver.
2. Select "Search for the best driver in these locations" and choose "Specify a location".
Type in "D:\" (where D:\ is the letter of your CD ROM drive) and click "Next" to continue.
3. Click "Next" to start the installation.
4. Click "Finish" to end this installation procedure.

Page 14
Modem LED Display
☞ When your modem is using V.90, the Front Panel Mode LEDs will display the speed
closest to the K56flex speed.
Transmit Data (TXD)
LED will flash when the modem is sending data.
Receive Data (RXD)
LED will flash when the modem is transferring data from the remote to the local computer.
Off-Hook
LED will glow when the modem is on-line; ie. dialling or answering
Carrier Detect
LED will glow when the modem detects a valid carrier signal from a remote modem.
Auto-Answer
LED will glow to indicate auto-answering operation. If the Global Carrier is performing a test,
the LED will flash until the test is completed or cancelled.
Terminal Ready
LED indicates the ‘Data Terminal Ready’(DTR) signal is asserted.

Installation
Page 15
Front Panel Mode LEDs
Line Modulation One Two Three Four
K56flex 56000 bps ✺M✺M❍❍
K56flex 54000 bps ✺M✺M●❍
K56flex 52000 bps ✺M❍❍❍
K56flex 50000 bps ✺M●❍❍
K56flex 48000 bps ✺M❍●❍
K56flex 46000 bps ✺M●●❍
K56flex 44000 bps ❍❍❍❍
K56flex 42000 bps ●❍❍❍
K56flex 40000 bps ❍●❍❍
K56flex 38000 bps ●●❍❍
K56flex 36000 bps ✺M✺M❍❍
K56flex 34000 bps ●❍ ●❍
K56flex 32000 bps ❍●●❍
K56flex 30000 bps ●●●❍
33600 bps ✺F✺F❍●
31200 bps ✺F✺F●●
28800 bps ✺F❍❍●
26400 bps ✺F❍●●
24000 bps ✺F●●●
21600 bps ✺M❍❍●
19200 bps ✺M●❍●
16800 bps ✺M❍●●
14400 bps ●●●●
12000 bps ●●❍●
9600 bps ❍●❍●
7200 bps ❍●●●
4800 bps ●❍❍●
2400 bps ✺S❍❍●
1200 bps ZS ❍●●
1200/75 bps ✺S●❍●
300 bps ✺S●●●
Fax 14400 bps ❍✺S✺S●
Fax 9600 bps ❍❍✺S●
Fax 7200 bps ❍●✺S●
Fax 4800 bps ●❍✺S●
Fax 2400 bps ●●✺S●
LED: ● = Off ❍= On
Flashing:✺S = Slow, ✺M = Med, ✺F = Fast

Page 16
The AT Commands
TheAT commands are a group of special commands recognised by your modem. These
commands derive their name from the lettersAT, which are used to prefix commands. Before
continuing:
• Run your communications software and enter local mode (or terminal mode) at 38,400 bps
Refer to your communication software manual for details.
The Attention Code
An AT (sometimes known as the ATtention code) usually precedes all commands being sent to
the modem. It is used to gain the modem’s attention, informing it that you are about to send a
command. For example:
• Type the command: ATI9 <E>
Your modem’s firmware identity message will appear on your computer screen. If you type I9
only, your modem will not respond. If you type AT19, your modem will report an ERROR.
You may enter the attention code in all upper case, or all lower case letters, such as: AT or at
Multiple Commands
You may place multiple modem commands after an AT provided the total number of characters
does not exceed 80. For example, a valid command to display the modem’s firmware identity
twice is:
• Type in the command: ATI9I9 <E>
An AT is not required in front of the second I9 command. You only need one attention code for
each command line. To make this command more readable, you can add spaces between the two
commands:
• Type in the command: AT I9 I9 <E>
The modem will execute the command as if the spaces are not there.
The Escape Sequence
When you issue commands to the modem all dialogue is occurring between your computer and
the modem. This situation is known as local command state.
When you connect to a remote system, dialogue will be occurring between your computer and
the remote system. This is known as on-line state. Because the modem assumes, after it enters
on-line state, all the data you send it is to be sent on to the remote modem, it ignores any AT
commands you give it while in on-line state.
To force the modem to return to local command state, enter an escapesequence. An escape
sequence consists of a one second delay, three + characters typed rapidly and another one
second delay. For example:

ATCommands
Page 17
• Type: AT&T1 <E>
The modem will enter on-line state (this command actually causes the modem to enter test
mode, but is equivalent to entering on-line state).
Now try to view the modem’s firmware identity code:
• Type: ATI9 <E>
Your command will be ignored. This is because the modem assumes you are typing characters to
be sent to a remote system.
Now enter an escape sequence. Do not type any characters for one second, type +++ rapidly
and wait another full second. The modem will respond with an OK message to indicate it has
returned to local command state. You will be able to view the modem’s firmware identity.
Beforecontinuing:
• Type: AT&T0 <E>
This command is used to halt the test.
The Repeat Command
The repeat command is used to re-execute the last command issued to the modem. Issue the
ATI9 command and the modem’s firmware identity code will be displayed on the screen.
• Type: A/
The identity code will appear again.
You don’t have to enter AT before the repeat command. You also do not have to press the
ENTER key. This is the only modem command which does not require you to enter AT before
it, and one of the few commands which does not require you to press the ENTER key. The A/
command is intended primarily for re-dialling a telephone number that was previously engaged.
The Help Command
Your modem will display information about the AT commands it supports if you type a
question mark (?) in your AT command.
Forexample:
• Type: AT? <E>
Your modem will display a list of all the commands it supports.
• Type: AT?DTR <E>
Your modem will display a summary of commands involving DTR.
• Type: AT?\N3%C2&D2 <E>
Your modem will display summaries of the \N, %C and &D commands.

Page 18
Response Codes
Your modem is capable of telling you, with on screen messages, what it is doing. These messages
are known response codes or result codes, and you will see them from time to time.
Forexample:
After a command is successfully executed, the response is: OK After a connection is established,
the response is: CONNECT A complete list of Response Codes can be found in Appendix A.
Dialling
TheAT commands may be used to initiate dialling with the modem. Your modem does not
require a telephone handset to be connected to it in order to dial.
The D (Dial) command is used to initiate a telephone call. The most basic form of the D
commandis:
ATD number where the number is the telephone number you are dialling.
Having set your communications software for 38,400 bps operation:
• Type: ATD01234 <E>
Your modem will begin to dial.
☞☞
☞☞
☞ If your modem receives a character from your computer while dialling is being
performed, it will immediately hang up, send a NO CARRIER response message to
the computer and return to local command state. After a few seconds the message
CONNECT will appear on the screen.
If a NO CARRIER message appears, then your modem has not been able to make a connection.
Check your communications software is set for 38,400 bps operation and your modem is
correctly connected to your computer and the telephone line. You may use the A/ command to
redial.
To hang up the modem, enter an escape sequence (+++). The modem will respond with an OK
message.
• Type: ATH <E>
The modem will hang up.
☞☞
☞☞
☞ Your computer must assert the DTR signal before dialling can start. Usually, this
is done by your communications software. If the DTR signal is lowered at any
stage of communications, after the &D2 command has been issued, the modem
will hang up and return to local command state. Interpretation of the DTR signal
may be changed with the &D command.

ATCommands
Page 19
Dial Modifiers
Dial modifiers are characters than can be included in a phone number to make the modem
perform special tasks while dialling. For example, not all modem users will be using a dedicated
telephone line. Some users will have their modems connected to PABXs. To allow users of
PABXs to operate their modems successfully, dial modifiers are supported on the modem.
Most PABXs require you to dial 0 or 9 (in order to obtain an outside line) and wait for a dial
tone before dialling the actual phone number. Using dial modifiers, you can successfully dial the
phone number 12345 through a PABX using the command:
ATD0,12345
The , (comma) dial modifier causes the modem to pause for a short time after dialling 0. This
allows most PABXs sufficient time to obtain a line before dialling.
The factory default delay for the , modifier is two seconds. You may change the length of this
delay if necessary. Its length is determined by the value in S Register 8.
Another method of making the modem wait for a dial tone is to include the W dial modifier. The
W modifier causes the modem to examine the phone line to ensure a dial tone has been applied
before dialling starts:
ATD0W12345
If the modem cannot detect a dial tone within the time specified by S Register 7, the modem will
return to local command state and send a NO DIALTONE message to the computer (if either the
X2, X4, or X5 commands have been issued).
Due to differences with some older telephone exchanges, dial tone detection may not be possible
with your modem. Your modem will only recognise dial tones between 200 Hz and 600 Hz.
If your telephone line supports tone dialling then a useful dial modifier is the T modifier.
Inserting a T modifier before the number you are dialling causes the modem to tone dial that
number. For example:
ATDT12345
This will cause the modem to dial the phone number 12345.
These modifiers may be placed at any point in the number you are dialling and they may be
intermingled in the same number. More information about dial modifiers can be found in the
Command Descriptions chapter of this guide.

Page 20
Hanging Up
The H command is used to hang up the modem.After you have finished communicating with
another computer you must hang up your modem. Similarly, you must hang up the phone after
calling another person. If you don’t, no one will be able to call you and you may even be charged
for the length of time the phone was off the hook.
To hang up your modem:
• Type: ATH <E>
The modem will return an OK response message.
Stored Number Dialling
Your modem has the ability to store phone numbers which may be dialed at a later time. This is
similar to ‘abbreviated dialling’, which may be supported by your telephone.
To store a phone number use the &Z command. For example:
• Type: AT&Z1=012345 <E>
The phone number 012345 will be stored as phone number one. The S dial modifier is used to
dial a phone number that has been stored in your modem:
• Type: ATDS=1 <E>
The modem will dial stored phone number one.
☞☞
☞☞
☞ Do not include an AT, D command, or S dial modifier in the stored phone number.
If synchronous mode 2 is being used, the ; (semi-colon) dial modifier should not
be included.
Answering Calls
As well as dialling other modems, your modem can answer calls made to it by other modems.