Contents:

Product Features

Installing Your Modem

Using the AT Command Set

Upgrading your Modem

Modes of Operation

Dialing, Answering, and Hanging Up

Configuring with DIP Switches

Working with Memory

Controlling Result Code Displays

Controlling EIA-232 Signaling

Accessing and Configuring the Courier 56K Business Modem Remotely

Controlling Data Rates

Dial Security

Flow Control

Handshaking, Error Control, Data Compression, and Throughput

Displaying Querying and Help Screens

Testing the Connection

Dedicated/Lease Line and Synchronous Applications

Troubleshooting

Appendixes

S-Registers

Alphabetic Command Summary

Flow Control Template

Result Code Meanings and Sets

Technical Information

V.25 bis Reference

ASCII Chart

Fax Information for Programmers

Viewing LEDs

Regulatory Information and Limited Warranty

Glossary

Courier 56K Business Modem Command Reference

Dialing, Answering, and Hanging Up

This chapter contains information about:

 

Dialing

You can use your modem to dial a specific telephone number and execute dial options by using the following commands.

Dial options

For your modem to
Command
Dial the specified phone number and execute dial options (DO NOT use spaces or dashes).
ATD phone number
Tone dial.
ATDT
Pulse dial.
ATDP
Pause for the length of time specified by S-Register 8. The default is 2 seconds.
ATD, (Comma)
Pause for 125 milliseconds.
ATD/ (Slash)

Wait for a second dial tone before continuing dialing.

This command only works if the X3 (or higher) command has been issued (see the Controlling Result Code Displays chapter and the Result Code Meanings and Sets appendix in this guide). If the modem is set to X2 or lower, it interprets the W as a two-second pause.

ATDW
Wait for an answer (with X3 or higher).
Some online services answer the phone and return a tape recorded request for information before processing transactions.
Use the AT@ command to tell the modem to detect at least one ring, wait for five seconds of silence at the other end of the call, and then continue.
To use the AT@ command, set the modem to X3, X4, or X7.
If set X2 or lower, the modem will return an ERROR message when it encounters the @ character. If set to X5 or X6, the modem hangs up when it detects a voice answer.
ATD@
Return to Command mode after dialing.
ATD; (Semicolon)
Dial the letters that follow (in an alphabetical phone number).
ATD"
If you are including another command after the phone number, use closing quotation marks before the additional command.
Note: With the exception of the above Dial options, your modem will ignore any commands issued after the D in the same command string.
Display different sets of result codes. See the Controlling Result Code Displays chapter and the Result Code Meanings and Sets appendix in this guide.
ATX2D..... X7D
Dial the last-dialed number. Use ATDL instead of using A/ if you wish to send the modem non-Dial commands before dialing again.
ATDL
Display the last-dialed number.
ATDL?
Dial the number stored in nonvolatile random access memory at position n, where n = 0-9. See the Working with Memory chapter in this guide, for instructions about saving phone numbers to memory.
Digits 0 through 9, * and # are accepted.
ATDSn
Stop dialing or stop repeating.
Type any key

Reissue the last command (Don’t type AT or press <ENTER>).
A/
Dial a number, wait 60 seconds for a connection, and then hang up. Wait two seconds, then redial. Make a maximum of 10 attempts.
To stop the repeating, press any key during the pause between dial attempts. If you press any key while the modem is dialing, that dial attempt is canceled but the cycle will continue
>
Dial the last-dialed number and repeat it just as the > command does. Also can be used to repeat any command.
A>


 

Carrier Loss Redial

You can set the Courier 56K Business Modem to redial the last-dialed number after it loses carrier (carrier is the signal maintained between two modems while they are on line). This feature is useful for dialed-line connections that operate unattended.

 
For your modem to
Command
Disable carrier loss redial
ATS69.1=0
Enable carrier loss redial
ATS69.1=1

Wait n seconds between losing the connection and redialing.

This command also defines the interval (in seconds) between dialing attempts if the first attempt is not successful.

ATS44=n

Example: Sending ATS44=20 sets a 20-second interval between losing the connection and redialing.

 

Answering Calls

Your modem can be configured to answer calls. By default, your Courier 56K Business Modem will not automatically answers calls.

Force Answer Mode

For your modem to
Command
Go through the answer sequence when it hasn't received an incoming call

Or

Manually answer a call
ATA



Auto Answer

You can set your modem to Auto Answer using the ATS0 command.

For all Courier 56K Business Modems except the PC card version, DIP switch 5 overrides the ATS0=n setting.

For your modem to
Command
Receive calls unattended (Auto answer enabled)

Remember to set your communications software to save incoming messages and/or files.
ATS0=1 (this instructs the modem to answer on the first ring)
NOT receive calls unattended (Auto answer disabled) ATS0=0

Example: Sending ATS0=0 will not allow your modem to receive calls when you are not present.

Note: See the S-Register summary in the S-Registers chapter of the Appendixes section for more information about instructing the modem to answer after more than 1 ring.

When your modem senses a call coming in, it sends the result code RING to your computer, goes off hook, and negotiates for a connection. If there is no response within 60 seconds, the Courier 56K Business Modem hangs up.

For more information about adjusting the 60-second wait-for-connection time using S-Register 7, refer to the S-Registers chapter of the Appendixes section.

When a call is disconnected, the Courier 56K Business Modem hangs up and returns the NO CARRIER result code.

Note: If S0=0, Auto Answer is disabled. To determine if Auto Answer is NOT disabled send the command ATI4 and be sure that S0=1-255.

Hanging up

If you want to end a connection with a remote device do the following:

  1. Enter Online Command Mode by typing +++
  2. Wait for OK from the modem
  3. Type ATH


 

Making International Calls

Guard tone

The AT&Gn command only applies to analogue international calls at 2400 or 1200 bps.

To set your modem for
Command
Required in these countries
No guard tone AT&G0 (Default) United States and Canada
550-Hz guard tone AT&G1 Some European countries
1800-Hz guard tone AT&G2 The U.K. and some Commonwealth countries


Note: If you set &G2 you must also send ATB0 to the modem. This setting allows the Courier 56K Business Modem to answer all calls from overseas.

 

Call Detection

Call Detection allows the modem to recognise whether an incoming call is analogue data or fax.

Call Detection is an optional Service Class 2.0 feature and is also implemented by U.S. Robotics for Fax Class 1 applications.

 

Caller ID Functions

Caller ID is a service provided by local telephone companies. When you subscribe to Caller ID, your phone company begins providing you real-time information about incoming calls.

The Caller ID signal includes the date and time of the call, the phone number of the calling device, and, optionally, the name of the calling party. The signal is sent between the first and second rings and must be decoded and displayed by a device connected to your phone line. The Courier 56K Business Modem has the ability to decode and display the Caller ID information.

Service Types

You can subscribe to Basic or Extended Caller ID service. Basic service offers you the date and time of the call and the calling party’s telephone number. Extended service provides the billing name associated with the calling party’s telephone number in addition to the Basic service information.

The information the Courier 56K Business Modem actually receives depends on the service type to which you’ve subscribed, the information that the calling party’s telephone company provides, and whether the equipment in between supports Caller ID. At minimum, you will always receive the date and time that a call arrived.

If a call arrives without a Caller ID signal, the modem will send OUT OF AREA in place of the phone number and name. If the Caller ID information has been blocked by the user at the other end, the Courier 56K Business Modem will send PRIVATE in place of the phone number and name.

Applications of Caller ID Technology

You can use Caller ID to screen calls, keep a record of calls, or prevent unauthorised access to your network. Third-party database and telephony applications such as security, call logging, and black-listing applications exploit the Caller ID information provided by the Courier 56K Business Modem.

How the Courier 56K Business Modem Handles Caller ID

When the modem receives the Caller ID signal, it stores the information in memory. You can access the information at any time by sending ATI15 to the modem.

ati15
U.S. Robotics V.Everything Corporate CID Status…
80 1E 01 08 31 30 31 35 32 30 33 38 02 0A 37 30
38 35 35 35 30 30 30 31 07 0C 55 2E 53 2E 52 4F
42 4F 54 49 43 53 22
DATE
=
1015
TIME
=
2038
NMBR
=
8475550001
NAME
=
U.S. Robotics
OK


Using the #CID command (described below), you can have the Courier 56K Business Modem send the information to your computer between the first and second RING messages. The Caller ID information is displayed only once.

RING
DATE
=
1015
TIME
=
2038
NMBR
=
8475550001
NAME
=
U.S. Robotics
RING

The information remains in memory until either you reset the modem or until it receives another valid Caller ID signal.

Note: To be sure that the Courier 56K Business Modem receives the Caller ID signal when auto-answer is enabled, set S0=2 or higher or make sure your communications software is set to answer on 2 or more rings.

Presentation Formats

The Courier 56K Business Modem sends the Caller ID information to your computer formatted or unformatted. Formatted presentation is a translation of the Caller ID signal into ASCII text. Unformatted presentation is a hexadecimal representation of the Caller ID signal.

An Example of Formatted Caller ID presentation:

RING

DATE = 1015
TIME = 2038
NMBR = 8475550001
NAME = U.S. Robotics

RING

An Example of Unformatted Caller ID presentation:

RING

801E01083130313532303338020A37303835353530303031070
C552E532E524F424F5449435322

RING

Commands

The following table describes the AT#CID=n settings.

Caller ID Action Command
Disable Caller ID detection and reporting AT#CID=0
(Default)
Enable Caller ID with formatted output AT#CID=1
Enable Caller ID with unformatted output AT#CID=2
Enable Caller ID with formatted output and name suppressed AT#CID=3
Enable Caller ID but do not transmit the information to your computer—retain it in the Courier’s memory AT#CID=4
Display the current caller ID setting AT#CID?
Display the Caller ID settings that are available AT#CID=?

 

 

Distinctive Ring Support

Distinctive ring is a service provided by local telephone companies that permits the assignment of multiple phone numbers to one line. Each phone number is associated with a different ring pattern, and devices that recognise distinctive ring, like the Courier 56K Business Modem, can be set to answer only on certain incoming ring patterns.

For example, a fax machine, answering machine, telephone, and modem could all share the same line. Each device would have its own phone number and respond only to calls intended for that number.

There are four ring patterns in common use:

Ring
Description
A
1.2 to 2.0 seconds on, 4.0 seconds off.
B
0.8 second on, 0.4 second off, 0.8 second on, 4.0 seconds off.
C
0.4 second on, 0.2 second off, 0.4 second on, 0.2 second off, 0.8 second on, 4.0 seconds off.
D
0.3 second on, 0.2 second off, 1.0 second on, 0.2 second off, 0.3 second on, 4.0 seconds off.

 

Commands

For your modem to
Command
Enable recognition of Ring A
ATS70.0=1
Disable recognition of Ring A
ATS70.0=0
Enable recognition of Ring B
ATS70.1=1
Disable recognition of Ring B
ATS70.1=0
Enable recognition of Ring C
ATS70.2=1
Disable recognition of Ring C
ATS70.2=0
Enable recognition of Ring D
ATS70.3=1
Disable recognition of Ring D
ATS70.3=0


Example: Sending ATS70.0=1.3=1 to your modem enables the recognition of ring types A and D only.

When a call comes in with a ring type A or D, the Courier 56K Business Modem will send the result code RING A or RING D, respectively. The Courier 56K Business Modem will ignore other ring types.

If S70 is set to 0 (the default) the Courier 56K Business Modem detects ring types A and B, sending the result code RING for either ring type. This function is identical to that of other U.S. Robotics modems that do not support distinctive ring.

If only one ring type is enabled, the Courier 56K Business Modem will recognise only the enabled ring type and ignore all others. It will send the result code RING only when it detects the ring type that's enabled.

If more than one ring type is enabled, the Courier 56K Business Modem will recognise only the enabled ring types and ignore the others. When a call arrives, the Courier 56K Business Modem will send its ring type in the result code, for example, RING C.

Australia distinctive ring patterns:

Ring
Description
A (Telstra “DR0”)
0.4 second on, 0.2 second off, 0.4 second on.
B (Telstra “DR3”)
0.2 second on, 0.2 second off, 0.4 second on.
C (Telstra “DR6”)
0.2 second on, 0.2 second off, 0.2 second on, 0.2 second off, 0.4 second on.
D (Telstra “DR7”)
0.2 second on, 0.2 second off, 0.2 second on, 0.2 second off, 0.2 second on.


UK distinctive ring patterns:

Ring
Description
A
0.4 second on, 0.2 second off, 0.4 second on.
B
0.4 second on, 0.2 second off, 1.0 second on.
OR
1.0 second on.
C
0.25 second on, 0.25 second off, 0.25 second on, 0.25 second off, 0.25 second on.
D
0.4 second on.
E
2.0 seconds on.


Result Codes

Verbal
Numeric
RING A
170
RING B
171
RING C
172
RING D
173
RING E
174



 


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