CXR V.34bis series Operation And Installation Manual

V.34bis Series

Standalone & Rackmount

Modems

Operation and Installation Manual

This publication contains information that is the property of CXR Telcom Corporation. No part of this publication may be copied, photocopied, reproduced, translated, or reduced to any electronic medium or machine readable form without prior written consent of CXR Telcom Corporation. Information in this publication is subject to change without notice. CXR Telcom assumes no responsibility for errors or omissions in this publication or for the use of this material.

9001

or more information on CXR Telcom products, contact:

ation CXR Telcom Corpor

47233 Fremont Boulevard F

remont, CA 945338-6502

(

510) 657-8810 • (510) 657-1158 • E-Mail: marketing@cxr.com

The V.34bis Series Standalone & Rackmount Modems are products of CXR T

elcom Corporation.

Printed in the USA.

Table of Contents

1. INTRODUCTION ........................................................................ 1

How To Use This Manual................................................................. 1

Product Description........................................................................ 3

Standard Features......................................................................... 3

Standard Features......................................................................... 4

2. INSTALLATION AND CONNECTION............................................ 7

Receiving and Unpacking................................................................ 7

Package Contents....................................................................... 7

Installation Requirements............................................................... 8

Telephone Line Access................................................................ 9

System Start-Up ........................................................................... 9

External Dial-Up Modems...........................................................11

Rackmount Modem Card ............................................................14

Switch Settings ............................................................................16

Power On Test..............................................................................17

3. MODES AND CONFIGURATIONS.............................................. 19

Common Operations .....................................................................19

Selecting a Factory Configuration ...................................................21

Selecting a Configuration By AT Command.......................................22

Special Reset ...............................................................................22

Factory Default Configurations .......................................................26

Originate A Call.........................................................................38

Answer A Call ...........................................................................38

Disconnecting...........................................................................39

Busy-Out.....................................................................................40

Password Security.....................................................................43

Pass-Through Access.................................................................45

Answer back.............................................................................45

V.34bis Series Standalone & Rackmount Modems i

Table of Contents

4. FRONT PANEL CONFIGURATIONS ............................................62

External Front Panel Operation ...................................................... 62

Rackmount Front Panel Operation.................................................. 67

5. LEASED LINE ............................................................................ 73

Originating Modem....................................................................... 74

Answering Modem........................................................................ 74

Manual Dial Back-Up ................................................................... 80

Change Real Time and Date .......................................................... 80

6. AT AND V.25BIS COMMAND SETS ...........................................81

AT Commands by Function............................................................ 81

7. S-REGISTERS........................................................................ 115

S-Register Functions ...................................................................115

8. MAINTENANCE AND TESTING.................................................125

Modem Testing...........................................................................126

Guide To Testing.........................................................................126

AT Test Commands.....................................................................127

APPENDIX A...............................................................................133

Product-line Warranty .................................................................133

APPENDIX B ............................................................................... 135

FCC & Canadian Regulation Info ...................................................135

APPENDIX C ............................................................................... 138

Specifications.............................................................................138

RS-232 Pin Assignments..............................................................142

APPENDIX D............................................................................... 142

INDEX ........................................................................................144

ii V.34bis Series Standalone & Rackmount Modems

Introduction

Thank you for purchasing a CXR Anderson Jacobson high-speed modem with fax capabilities. You have purchased one of the finest modems available. Depending upon the model you have chosen, your modem will provide you with data communication rates up to 33,600 bps. Group III fax communications at 9600 bps is also a feature of your new AJ modem. AJ modems also provide the benefits of error correction and data compression to enhance the reliability and efficiency of the data communications.

AJ modems are compatible with ITU-T V.34, V.32terbo, V.32bis, V.32, V.42, or V.42bis standards, as well as the applicable Bell standards listed in the Product Description of this manual.

How To Use This Manual

This manual consists of eight chapters as well as appendices and an index. The appendices serve as a quick reference for detailed information provided in the chapters. A listing of the chapters with a brief description of their contents follows:

1- Introduction

This chapter provides information on manual organization as well as an introduction and a detailed description of the AJ modem.

2 - Installation & Connection

Installation and connection leads you through the procedures to unpack, inspect, and install your modem. Also included are requirements for minimum PC system configurations and rack systems.

3 - Modes & Configurations

This chapter describes how to control and configure the modem. Descriptions of common operations, and selecting a factory configuration are also included.

4 - Front Panel Operation

Front panel operation describes the operation and function of front rackmount and external panel controls and indicators. Included are descriptions of the DL/DIS operation and a summary of LED indicators and functions.

5 - Leased Line Operation

V.34bis Series Standalone & Rackmount Modems 1

Introduction

Includes information for 2 and 4-wire leased line modes, Unattended and Manual Dial Back-Up.

6 - AT and V.25bis Operation

The operation of the AJ modem using the AT command set is described in this chapter. Listing of the AT commands by function as well as alphabetical order are provided. V.25bis commands are provided at the end of this chapter

7 - S-Registers

This chapter discusses S-registers used to store configuration parameters.

8 - Maintenance and Testing

This chapter covers testing and diagnostic steps used to help isolate communication problems.

Appendix A - Product Line Warranty Appendix B - FCC and Canadian Regulations Appendix C - Specifications

Appendix D - RS-232 Pin Assignments Index

2 V.34bis Series Standalone & Rackmount Modems

Introduction

Product Description

This manual describes the operation of the 3 types of AJ High-Speed Modems; external, internal and rack mountable. These modems also come in either line or dial up configurations. AJ modems provide up to 33.6K bps modem data communications and Group III, Class 1 and 2 leased line fax send/receive at 9600 bps. Both configurations are downward compatible with V.22/V.22bis, Bell 103 and 212A modems operating at speeds as low as 300 bps. Significant non-volatile memory is provided to store and recall multiple operating configurations, telephone numbers and security codes. Remote configuration monitoring and control and extensive security modes are also provided.

Standard Features:

• V.34 Compatible; 33.6K bps full duplex operation

• V.34 Compatible; 28.8K bps full duplex operation

• V.32terbo Compatible; 19.2K bps full duplex operation

• V.32bis Compatible; 14.4K bps full duplex operation

• V.32 Compatible; 9600 bps full duplex operation with trellis coding

• V.23, V.22bis, V.22, V.21, and Bell 212 and 103 compatible; at 2400,

1200 and 300 bps full duplex operation

• 2 and 4-Wire Leased Line Operation with Unattended Automatic Dial

Back-Up (UADBU) (Leased Line models only)

• Group III, Class 1 and 2 Fax Transmission at 9600 bps w/fallback to

7200 or 4800 bps

• Expanded "AT" Commands

• V.42 (LAPM) Error Correction and V.42bis Data Compression

• MNP Class 4 Error Correction/MNP Class 5 Data Compression

• Dial-Up Operation

V.34bis Series Standalone & Rackmount Modems 3

Introduction

Standard Features Continued:

• "Good Connection" feature obtains an acceptable dial line

• Simulated Half-Duplex Operation as Defined by ITU-T V.13

• 10 Stored Configurations

• Remote Configuration Monitoring and Control

• Synchronous and Asynchronous operation

• Non-volatile Memory for storing parameters and phone numbers

Dialer Features

• Asynchronous "AT" expanded command set for dialing

• Alternate ITU-T V.25bis dialer

• Pulse, tone and adaptive dialing

• Second dial tone detection

• Single command redial operation

• Dialing from the PC keyboard

• Automatic redial when the connection provides poor signal quality or

loss of carrier is detected

• Storage of 100 telephone numbers of a maximum of 25 digits each

• Each stored telephone number can have a different user defined

modem configuration

• Dialing from stored numbers by: ◊ location number ◊ link to another number ◊ DTR or front panel switching ◊ name (mnemonic)

4 V.34bis Series Standalone & Rackmount Modems

Introduction

Security Features

• Answerback

• Pass-through Access

• Callback

• Automatic Modem Password Access

• Operator Password

• Supervisor Password

Test Features

• Power-up self-test

• Local digital loopback per ITU-T V.54

• Local Analog Loopback

• Remote Digital Loopback

Power Supplies (External Models Only)

The power supply module for the external model is supplied with the modem. It provides regulated + 5 VDC through a single cable that plugs into the rear of the modem. The standard module is plugged into a dedicated wall receptacle or high quality power strip that must provide a nominal 117 VAC at 60Hz.

V.34bis Series Standalone & Rackmount Modems 5

Introduction

6 V.34bis Series Standalone & Rackmount Modems

Installation and Connection

Receiving and Unpacking

Examine the boxes when the equipment is received. If signs of damage or rough handling are evident, have the carrier's agent present when the equipment is unpacked. Unpack the equipment carefully. Inspect it for scratches, dents, cracks, or any other signs of damage. If the equipment is damaged, save all the packing materials and notify both CXR Anderson Jacobson and the carrier immediately. AJ will arrange for repair or replacement of damaged equipment without waiting for settlement of claims with the carrier. Check your packing list to verify you have received all your equipment. In case of a shortage in any of the items for your particular DSU, please contact your local distributor or CXR AJ Customer Service at (800) 537-5762 .

Package Contents:

Your modem comes in a protective carton along with a number of other items. The contents of the box will depend upon whether you have purchased an internal or external AJ modem model.

External Modem

Rackmount Modem Card

Rackmount Modem Card in Standalone Chassis

In case of a shortage in any of the items for your particular modem, please contact your local distributor, or CXR Customer Service at (510) 657-8810.

• AJ High Speed Modem Manual

• RJ-11 dial-up phone cable

• DC Power Supply

• AJ High Speed Modem Manual

• (1) 4-pin Telco Cable

• (1) 8-pin Telco Cable

• AJ High Speed Modem Manual

• (1) 4-pin Telco Cable

• (1) 8-pin Telco Cable

V.34bis Series Standalone & Rackmount Modems 7

Installation

Installation Requirements

This section explains how to install the AJ High Speed modem in the rackmount chassis or standalone case.

Items Needed to Install a Dial-Up External Modem

√ PC with an RS-232 serial port

√ RJ-11 telephone jack

√ An RS-232 shielded cable with a 25-pin D-type connector for the

modem-to-DTE connection

√ A telephone set (optional) only if voice operation is needed

Items Needed to Install a Leased Line External Modem

√ A DTE, PC or terminal with an RS-232 serial port

√ A RJ-45 telephone line jack, and leased line connections terminated in

a JM-8 jack

√ An RS-232 shielded cable with a 25-pin D-type connector for the

modem-to-DTE connection

√ A telephone set required only for manual dial back-up operation

Items Needed to Install a Rackmount Modem

√ Power Cord (Standalone chassis only)

√ Two telephone cables (one with RJ-11 plug at both ends for dial line

connections, and one with RJ-45 plug at one end and spade lugs at other for leased line connections)

√ DTE (Data Terminal Equipment) with an RS-232 serial port

√ A telephone line jack - either RJ-11 or RJ-45

√ Operator's Manual

√ RS-232 shielded cable with a 25 pin D-type connector for the DTE-to-

modem

√ AJ rackmount chassis or standalone case

Location Factors

8 V.34bis Series Standalone & Rackmount Modems

Installation

Determining the optimum location is the combination of several factors and compromises. For the desktop installation it is a matter of operator convenience and effectiveness, and the modem's proximity to line power, to the telephone wall jack, to the telephone set (if it is to be used with the modem) and to the location of the terminal equipment.

The rackmount chassis is typically located in a cabinet/rack that holds other equipment or other rackmount chassis of modems. Adequate line power for all the equipment in the cabinet must be available or brought to the chosen location. The modem printed circuit assemblies (cards) require about 15 inches in front of the cabinet to be plugged in and out of the rackmount chassis. Since an operator is expected to walk in front of the cabinet to operate and observe the front panel on some occasions the space for passage should at least be the 15 inches needed for the modem.

The rackmount modems and their chassis are designed with free airflow in the vertical direction to provide natural convection cooling. The specifications for the modems require a maximum ambient temperature for the modem card of 122° degrees F. The modem rackmount chassis may be stacked and the air will flow through the stack, but the considerations of the temperature and the flow of the air become more critical. When rackmount modem chassis are located in cabinets with other equipment that would block the convection cooling it is necessary to provide a minimum of one and one-half inches of unobstructed space at the top and bottom so that airflow is not restricted. When the heat generated by the equipment in the cabinet cannot be ventilated by convection cooling then forced airflow is required. This may be done by the addition of a blower assembly to the cabinet to force air through the equipment. In a computer room there may be cooled air moving through ducts that may be vented into the cabinet by only providing the appropriate openings in the floor.

Telephone Line Access

The proximity to the telephone lines must be considered in the planning phase of the installation. The consideration of routing dial lines from a corporate PBX system may be involved and require consultation with the group that maintains the PBX system. The routing of bundles of cables and the consideration of the 50 pin connector termination or the use of multiple RJ-45 type jacks requires analysis. The future expansion or changing requirements of the data communication system may become a part of this decision. The use of digital lines has many of the same considerations, but it is more likely that the Bell Operating Company serving your facility must be consulted for determining the location for the line installation effort and the type of connections that are the most reasonable for now and in the future. The schedule for the planned telephone line installation may become a critical part of completing the installation in a timely manner.

System Start-Up

V.34bis Series Standalone & Rackmount Modems 9

Installation

A common start-up procedure applies after the modem installation is completed through the power on sequence. Your AJ Modem is shipped from the factory with a common default configuration. The factory settings for the various modem functions are presented in Table 3.1. This configuration is stored in non-volatile memory and can be reviewed at any time by the user with the status AT&Sn command (see Chapter 3). If the "n" position is omitted then the full twelve pages are presented, but the continuation of the status display can be aborted by typing any character except <enter>. If n = the desired page of the status display, then only that page is presented

After connecting the modem to the DTE and to the telephone line or lines, the user should look over the option settings and note which items must be changed from the factory settings to configure the modem appropriately for the system and application being used. As shipped, the User Configuration 0 is the same as the dial-up Factory Configuration 0.

10 V.34bis Series Standalone & Rackmount Modems

Installation

TEL SET TEL LINE TERMINAL POWER OFF ON

Figure 2.1: How to Install the External Dial-Up Modems

1. Place the modem on a surface near an AC outlet, the RJ-11 telephone wall jack and your PC.

2. Connect the modem to the telephone line. Insert one end of the telephone cable into the modem jack marked "TEL LINE" and the other end into the telephone wall jack.

3. Connect your telephone (optional). Connect the telephone cable from the telephone set to the modem jack marked "TEL SET".

4. Connect the modem to your PC. Attach the RS-232 cable from the serial port to the modem connector marked "TERMINAL". Read your PC owner's manual to locate the serial port.

5. Turn the modem power switch OFF. Connect the power supply cable into the connection marked "POWER" on the modem. Plug the power supply into a standard three-prong AC wall outlet.

6. Turn the modem power switch ON. The modem will perform a selftest. If the modem passes the self-test, three short beeps will be heard. Failure is indicated by four lower pitch tones. If a failure occurs, turn off the modem, check all connections, and try again. If modem still fails, call Technical Support.

COM Port

Most PCs and PC-compatibles have two serial ports usually COM1 and

COM2. Some also have COM3 and COM4. Make sure your modem

software is set to the correct COM Port.

V.34bis Series Standalone & Rackmount Modems 11

Installation





Figure 2.2: External Modem Switches and Jumpers

Simple

With Telephone

Answering Machine

Modem

Wall Jack

Answering

Wit h Te l e ph o ne

Modem

Machine

Modem

Wall Jack

Figure 2.3: Connecting the Wiring for a Dial-Up

External Modem

12 V.34bis Series Standalone & Rackmount Modems

Installation

LEASE LINE TEL LINE TERMINAL POWER OFF ON

Figure 2.4: Installing the External Leased Line Modem -

2/4-Wire

Installing the Modem

To install the modem, place it on a convenient surface within reach of an AC outlet, the telephone dial line connector and leased lines, and the associated DTE (Data Terminal Equipment).

Connections

The rear of the external leased line modem has three modular jacks labeled: LEASE LINE and TEL LINE. Determine which jacks are utilized for the required application based upon the following:

• LEASE LINE Used for 2/4-Wire lease line applications, or as the

telephone set connection for dial-data applications. This allows for manual dialing or voice. When using the Automatic Dial Back-Up feature, the telephone line jack is

• TEL LINE Used for the normal switched network connections to the

V.34bis Series Standalone & Rackmount Modems 13

required to access the dial network.

telephone line from the wall. Supports MI/MIC operation for use with PBX systems, automatic call units and telephone sets with an exclusion key.

Installation

Rackmount Modem Card Installation

The AJ modem card can be used in a chassis with other modems, or in a standalone case. The chassis provides printed circuit connections to the EIA and the telephone line connectors.

The AJ modem chassis has 16 single-card slots to hold 8 of the AJ LCD modems or 16 standard modems. Different types of modems may be mixed in the same chassis. The AJ UCSA-03 standalone case will hold one single or a double card slot modem.

RJ-11/45 SIGNAL

L/L-1 LEASED LINE TRANSMITTER L/L-2 LEASED LINE TRANSMITTER GROUND L/L-7 LEASED LINE RECEIVER GROUND L/L-8 LEASED LINE RECEIVER

D1-4 DIAL 1 PHONE TIP D1-5 DIAL 1 PHONE RING

D2-3 DIAL 2 MODE INDICATOR D2-4 DIAL 2 LINE RING D2-5 DIAL 2 LINE TIP D2-6 DIAL 2 MODE INDICATOR COMMON

Table 2.1: Connections to RJ-11/45 Connectors to Telco

PIN POSITIONS

8 7 6 5 4 3 2 1

PIN POSITIONS

1 2 3 4 5 6 7 8

Smart Rack Configuration UCSA-XX Configuration

Telco Jack Pin Number

1-gray 5-red 2-orange 6-black 3-yellow 7-blue 4-green 8-brown

DIAL 1 connects to the telephone set. DIAL 2 connects to the telephone line from the wall. LL connects to the leased line cable from the Telco.

14 V.34bis Series Standalone & Rackmount Modems

Installation

Figure 2.5: Rackmount Switches and Jumpers

Standard Rackmount Assembly Shown in Factory Default Position

Note: Short J10 to disable the "AT" command function

V.34bis Series Standalone & Rackmount Modems 15

Installation

Switch Settings for Leased Line Modems

In order to adapt the modem to work with non-standard interfaces and to take advantage of the extra features of the modem, there are two sets of dip switches (S1 and S2) of eight switches each which will configure the signals on the serial (RS-232) interface. The following Section provides a listing of the alternate EIA signals available with alternate switch settings.

External Series Modems - DipSwitch Default Settings

S1-1 ON RDL control using pin 21 S1-5 ON Speed control using pin 23 S2-3 ON LAL control using pin 25

Alternate Signals/Switch Settings for EIA Interface

For Signal Quality output to pin 21: Set S1-1 & S1-4 OFF then set S1-2 ON.

For Signal Quality output to pin 11: Set S1-2 & S1-3 OFF then set S1-4 ON.

For RDL command input from pin 21: Set S1-2 & S1-3 OFF then set S1-1 ON.

For RDL command input from pin 11: Set S1-1 & S1-4 OFF then set S1-3 ON.

For Speed command input from pin 23: Set S1-6 OFF then set S1-5 ON.

For Speed indication output to pin 23: Set S1-5 & S1-7 OFF then set S1-6 ON.

For Speed indication output to pin 12: Set S1-6 OFF & set S1-7 ON.

For Unattended Automatic Dial Back-Up indication output to pin 19: Set S2-1 ON.

For Unattended Automatic Dial Back-Up (UADBU) command input to pin 14: Set S2-2 ON.

For LAL command input from pin 25: Set S2-4 & S2-5 OFF then set S2-3 ON.

For Test indication output to pin 25: Set S2-3 OFF then set S2-4 ON.

ALL OTHER SWITCHES ARE OFF

16 V.34bis Series Standalone & Rackmount Modems

Installation

For LAL command input from pin 18: Set S2-3 OFF then set S2-5 ON.

Rackmount Modems

To force DSR ON: S2-6 ON To force CD ON: S2-7 ON To force CTS ON: S2-8 ON

External Series Modems

To force DSR ON: SW2-1 To force CD ON: SW2-2 To force CTS ON: SW2-3

SW2-4 is used for Dumb Mode

Power On Test

External Modems

Turn on the power to the modem by sliding the rear panel power switch to the ON position.

If the modem passes the power-up self-test, three short beeps will be heard. Failure is indicated by four lower-pitched tones and the LEDs will indicate the type of failure.

After the self-test, the DTR LED begins to flash if DTE is not connected or turns on if the DTE is connected and provides an on signal.

Rackmount Modems

With power applied to the rack, insert a module card into the rack.

If the modem passes the power-up self-test, three short beeps will be heard. Failure is indicated by four lower-pitched tones.

V.34bis Series Standalone & Rackmount Modems 17

Installation

18 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Common Operations

The AJ Modems are typically operated using the industry-standard AT command set. The AT commands for these modems have been expanded beyond the standard set in order to incorporate the many additional features that are included in these modems. AT commands are issued to the modem in Command Mode. The modem is in Command Mode when it is disconnected from the phone line. This is sometimes referred to as the Idle Mode.

An asynchronous communication program eliminates the need to learn the modem commands. All AT commands, except A/ and the escape code (+++) begin with the letters AT, meaning "attention". Several commands may share a line as a single string of commands, but only one AT prefix is required, at the beginning of the line. Each command consists of the following elements:

• The two character sequence AT

• A command

• A command parameter (optional)

• A carriage return

Example: To enter the command 'Answer', type ATA and <enter>.

If the subscript n = 0 is desired it is not necessary to type the "0". If the n position is left blank the modem assumes a "0". Table 6.2 provides the full details of the AT commands.

Some commands do not have parameters. Any missing parameter in a command is assigned the value zero, which may be a valid parameter for the command. The sequence followed by AT command causes the modem to enter a command state. That is, AT without a command serves as a wake up code and an "OK" appears on the screen.

The modem queues commands in a 40-character command line. The command line beginning with AT can have several commands. A separator is not required between the commands. The command line format is:

AT command (parameter)... (enter)

V.34bis Series Standalone & Rackmount Modems 19

Modes and Configurations

When a carriage return is received, which terminates the command line, the commands are performed in the order in which they are sent to the modem. If more them 40 characters are sent to the modem, an error occurs and all command must be re-entered.

Most users only need to use a small portion of the AT command set, the following paragraphs discuss how to perform the most common day-to-day modem functions utilizing the AT commands.

After a command is entered, the modem sends a message, or result code, to the terminal screen. Most commands are acknowledged by OK. The modem can be arranged to send the result code in words or as digits with the Word/Digit ATVn command. The most common result codes are:

WORD CODE DIGIT CODE MEANING

OK 0 Command line executed

without error.

CONNECT 1 Connection established.

RING 2 Ring signal detected on

the line.

20 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Selecting a Factory Configuration

The leased line/dial-up modems have five factory default and five user configurations. Any of these configurations can be called into action by the AT command set, by association with a dialed number, or by the front panel. The default factory configuration is for the most common application of dial-up operation (AT&F0).

The factory configurations are: Leased Line Factory Configurations 0 through 4

• DIAL-UP (AT&F0)

• 4W LEASED LINE ORIGINATE MODE (AT&F1)

• 4W LEASED LINE ANSWER MODE (AT&F2)

• 4 WIRE LEASED LINE ORIGINATE MODE W/UADBU (AT&F3)

• 4 WIRE LEASED LINE ANSWER MODE W/UADBU (AT&F4)

Dial-Up Factory Configurations 0 through 4

• DIAL-UP (AT&F0)

• DIAL-UP & DSR, CD, CTS FORCED ON (AT&F1)

• DIAL-UP & DSR, CD, CTS FORCED ON (AT&F2)

• V.25bis HDLC/SDLC (AT&F3)

• V.25bis BISYNC (AT&F4)

As shipped from the factory, "Factory Configuration 0" is also stored as the "User Configuration 0", "Factory Configuration 1" is also stored as "User Configuration 1", "Factory Configuration 2" is also stored as "User Configuration 2", "Factory Configuration 3" is also stored as the "User Configuration 3", and "Factory Configuration 4" is also stored as "User Configuration 4". The desired differences can then be entered and stored as user defined configurations. The factory configurations are defined in Table 3.1 by using the DIAL-UP, AT&F0, as the reference and the basic configuration.

V.34bis Series Standalone & Rackmount Modems 21

Modes and Configurations

Selecting a Configuration By AT Command

The AT&Fn command causes the modem to load the factory configuration "n" into the active memory of the modem, putting the modem into a known operating state. The AT%Mn command will load into active memory one of the user configurations "n" stored with the AT&Wn command, putting the modem into a known operating state.

The configuration can be used as it is, or modified to fit the application. If the configuration is modified, it can either be abandoned at the end of the session or stored into non-volatile memory with the AT&Wn command as shown below.

The AT&Wn command stores a new user-specified configuration in nonvolatile memory. The new configuration is based on the current settings of the modem S-registers. This new configuration will be active if it is associated with a number to be dialed or activated by the AT%Mn command.

FORMAT: AT&Wn where n = 0 - 4 for the user configurations %M0 through %M4 where n = 5 - 9 for the factory configurations &F0 through &F4

The modem will load the last configuration that was saved when it is powered up. A factory configuration can be used without deleting the user configuration as long as the factory configuration is not saved as the user configuration with the AT&Wn command.

Special Reset Command - AT&W255

This is a special command that resets the modem to the factory settings including the erasing of all telephone numbers and attributes stored, and the erasing of all passwords that may have been stored. However, this command does not compromise the password security features of the modem because if a supervisor password is stored then that password is required in order to enter this AT&W255 command. The stored configurations will be set to the factory conditions as given in Table 3.1. This may be a useful and a known starting point in setting the modem for differing applications. This special command is useful when the modem is moved to a new location or a new application is being implemented. By utilizing the AT&W255 the factory configurations are set at a known starting point, and telephone numbers, attributes and security features are erased for re-entry as required.

International Variations to the Configuration

When these modems are used for international calls, there are a few settings that should be changed. To receive a modem call from some European countries, the guard tone must be turned on. England requires

22 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

an answering modem to have an 1800 Hz guard tone. Some Danish central offices require a 550 Hz guard tone. The guard tones are turned on with the AT&Gn command. If a required guard tone is not present, the central office will disconnect the call within two minutes. When originating an international call, S-Register 7 should be set to 120 seconds (ATS7=120) to allow for the possible extended time for a call to be connected. This assures there will be enough time for the call to be connected and for the modems to train. Some software packages have a limit for the modem connect time, e.g. Crosstalk default is 30 seconds. Usually there is some way to increase the default time.

V.34bis Series Standalone & Rackmount Modems 23

Modes and Configurations

Timers

These modems have several timers that control the connection to the phone line and the modem-DTE connection.

> Command Mode Inactivity Timer: In Command Mode, if the

carriage return <CR> is not entered within 30 seconds after the AT entry, the command that follows is ignored. To resume work, you must enter AT again to wake up the modem.

> Online Inactivity Timer: If no data is transferred for the period of

time specified in S-Register 32, the modem will automatically disconnect from the telephone line. The inactivity can be related to transmit data only, receive data only or to both as determined by the AT%In command - see Chapter 6. The default is for the inactivity timer to be disabled, AT%I0. Also, if S32 set to 0 the inactivity timer is disabled. S32 may be zero or set to a positive value of 1-255 minutes (asynchronous mode only).

> Abort Timer: If no carrier tone is detected within the time period

specified in S-Register 7, the modem will drop the line. The default time period is 60 seconds.

> Loss of Carrier: If the modem loses carrier, it will disconnect from

the telephone line after the period of time specified by S-Register 10. The default is 2.0 seconds.

In Table 3.1, on the following pages, the first column displays the option, the second column indicates the current option setting, and the third column lists the associated AT command.

Note: An * (asterisk) in T able 3.1 preceding any option setting indicates

a change from the dial-up factory setting.

Status Display Page Configuration Category

1 Visual Display and Interface Signals 2 Dialing & Answering and On-line 3 Format/Data Rate and Leased Line 4 Flow Control and Break Handling 5 Error Correction and Action Commands 6 Security Information 7 Action Commands 8 Connect Status

9 Error Correction Status 10 Test Commands 11 Leased Line Statistics 12 Dial Line Statistics

24 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Factory Configuration Setting # 0

FACTORY CONFIGURATION 0 PAGE 1

VISUAL DISPLAY INTERFACE SIGNALS

COMMAND ECHO ON E1 DTR NORMAL &D2

QUIET

RESULT TYPE LONG V1 CARRIER OFF-

CALL PROGRESS 4 X4 CTS DTR-XMIT %C3

CONNECT MSG AT

SPEED MSG IS MODEM *N0 RTR POLARITY 0 *RP0

EXTENDED MSGS ON *V1 RTS TO CTS DLY 0 S26=0

<CR> CHAR ^M S3=13 EIA DISC TIME 1 S41=1

<LF> CHAR ^J S4=10 DSR/CD CLL BCK OFF *S0

<BS> CHAR ^H S5=8 EIA RDL CTRL OFF %ER0

EIA SPEED CTRL OFF %ES0

EIA LAL CTRL OFF %EA0

EIA DISC TIME 1 S41=1

SYNC DTR DELAY 0 S25=0

Type <enter> to continue:

FACTORY CONFIGURATION 0 PAGE 2

DIALING AND ANSWERING ONLINE

DIALER TYPE ASYNC AT @V1 TRELLIS ON @T1

ADAPT DIAL OFF %A0 XMIT EQUALIZER OFF @X0

DIAL METHOD TONE T LOSS CD TIME 20 S10=20

DTMF PULSE WID 70 S11=70 CD DETECT TIME 6 S9=6

PULSE RATIO 39/61 &P0 LOSS CD REDIAL OFF %Q0

BLIND DL TIME 2 S6=2 BELL OFF B0

"," PAUSE TIME 2 S8=2 LONG SPACE OFF Y0

BAD SQ REDIAL OFF &Q0 AUTO RETRAIN ON %R1

AUTO REDIALS 0 S55=0 RETRAIN TIMER 40 S31=40

ANY CHAR ABORT

ABORT TIMER 60 S7=60 SPEED CHANGE OFF @F0

DIAL XMIT LVL -10dBm %XD5 RESP RDL RQST ON @R1

SPEAKER CTRL 1 M1 GUARD TIME 50 S12=50

VOLUME 2 L2 ESC CHAR + S2=43

V.34bis Series Standalone & Rackmount Modems 25

2-W DIAL WITH AUTO-ANSWER, AT&F0

OFF Q0 DSR ANS

CARRIER *C0 RTS/RTR FORCED &R0

ON %B1 AUTO FALL BACK TRN&ONL %F3

TONE

CARR

%D2

&C1

Modes and Configurations

RINGS TO ANS 1 S0=1 DOWN LINE

GUARD TONE NONE &G0 INACTIVE TIMER DISABLE

V.22 BIS HUNT

ON %H1 INACTIVE TIME

Type <enter> to continue:

LOAD

Table 3.1: Factory Default Configurations

FACTORY CONFIGURATION 0 PAGE 3

FORMAT / DATA RATE

AUTO BAUD ON @A1 LEASED LINE OFF

CONSTANT DTE ON @C1 LEASED LN

DTE SPEED 38400 @D8 LEASE XMIT LVL -6 dBm

MODEM SPEED 33600 @M17 AUTO DIAL BKUP OFF

DATA BITS 8 @B8 FALL DWN LIMIT 0

PARITY NONE @P0 DIAL BKUP ALRM ON

STOP BITS 1 @S1 WEEKDAY

ASYNC/SYNC

SYNC CLOCK INTERNA

START HOUR 0 S74=0 WEEKEND

STOP HOUR 0 S75=0

WNDW END DISC OFF %Y0

LEASE LOOKBACK

LOOKBACK TIMER

Type <enter> to continue:

LEASE LINE

MODE

WINDOW

ASYNC &M0 START HOUR 0

OFF %L0

0 S56=0

&X0 STOP HOUR 0

WINDOW

FACTORY CONFIGURATION 0 PAGE 4

FLOW CONTROL BREAK HANDLING

DTE BUFF SIZE 1024 &B1 CMD AT BRK OFF *D0

GEN LOC FC CTS *LG2 PASS XMIT BRK IMMEDIA

GEN LOC XON ^Q S67=17 PASS RECV BRK IMMEDIA

GEN LOC XOFF ^S S68=19 CLR XBF XMIT OFF *KA0

^Z S38=26

0 S32=0

ORIGINAT E

OUTSIDE

%I0

&L0

%O1

%XL5

%U0

&40

%V1

%WD0

S72=0

S73=0

%WE0

*XK1

*RK1

26 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

RESP LOC FC NONE *LR0 CLR XBF RECV OFF *KB0

RESP LOC XON ^Q S64=17 CLR RBF XMIT OFF *KC0

RESP LOC XOFF ^S S65=19 CLR RBF RECV OFF *KD0

FILTER XMIT FC OFF *XF0 XMIT BRK TIME 0 S46=0

GEN REM FC NONE *RG0 RECV BRK TIME 0 S47=0

GEN REM XON ^Q S62=17

GEN REM XOFF ^S S63=19

RESP REM FC NONE *RR0

RESP REM XON ^Q S69=17

RESP REM XOFF ^S S70=19

FILTER RECV FC OFF *RF0

Type <enter> to continue:

V.34bis Series Standalone & Rackmount Modems 27

Modes and Configurations

Table 3.1: Factory Default Configurations - Continued

FACTORY CONFIGURATION 0 PAGE 5

ERROR CORRECTION ACTION COMMANDS

CORRECTED MODE

PROTOCOL TYPE LAPM/M

DET PHASE TIME 15 S87=15 START ERROR CORRECTION *Y

ERROR ALARM ON *G1 STOP ERROR CORRECTION *Z

BLOCK/STREAM

MAX PACK SIZE 256 *P3

ADAPT PACKET ON *A1

CORRECTED CHAR

LINK ABORT CHR 128 S52=128

DATA COMPRESS OFF *E1

BREAK TYPE NORMAL *KT0

ATTN BRK TIME 3 S48=3

Type <enter> to continue:

AUTO *M2 INITIATE ERROR CORRECTION *O

STREAM *B0

$ S50=36

*T3 ACCEPT ERROR CORRECTION *U

FACTORY CONFIGURATION 0 PAGE 6

SECURITY INFORMATION

ANSWERBACK: &A:ssssssssssss:ssssssssssss

PASSWORDS

SUPERVISOR: %PS:ssssssssssss:ssssssssssss

OPERATOR: %PO:ssssssssssss:ssssssssssss

SECURITY OPTIONS

"AT" COMMANDS OFF %SC0

NON-VOL WRITE OFF %SW0

ANSWER OFF %SA0

DOWN LINE LOAD OFF %SD0

RACK CONTROL OFF %SS0

PASSWORD OPTIONS

PROMPTS ON %SP1

ENTRY ATTEMPTS 1 TRY %ST0

CASE SENSITIVE OFF %SL0

AFTER CALLBACK OFF %SB0

28 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Type <enter> to continue:

Table 3.1: Factory Default Configurations - Continued

FACTORY CONFIGURATION 0 PAGE 7

ACTION COMMANDS

ANSWER A

DIAL Dssssssssssssssss

DIAL STORED NUMBER DSn

LIST STORED NUMBERS &N

STORE PHONE NUMBER &Zn:name:password:number:link:cnf:attr

SET CLOCK %Thh:mm:ss:mm-dd-yy

LOAD DEFAULTS

BUSY OUT OFF *H0

RINGS TO BUSY 0 S20=0

IDENTIFICATION In

HANG UP H

GO ONLINE O

LOAD FACTORY DEFAULTS &Fn

LOAD USER CONFIGURATION %Mn

STORE USER CONFIGURATION &Wn

RESET STATISTICS *RS

RESET MODEM Z

Type <enter> to continue:

ON RESET @L0

USER 0

FACTORY CONFIGURATION 0 PAGE 8

CONNECT STATUS

OFF LINE

CONNECT TIME 17:41:19

LAST DIAL 555-1234

Type <enter> to continue:

NOTE: When modems are on-line the display will resemble this

format:

ON LINE ORIGINATE

V.34bis Series Standalone & Rackmount Modems 29

Modes and Configurations

MODULATION 33600 V.34 or Î (Modulation Types)

SIGNAL QUALITY 9 V.34

RECEIVE LEVEL -33 dBm V.32terbo

ROUND TRIP DELAY 71 mS V.32bis

FAR END ECHO -66 dBm V.32

CONNECT TIME 00:00:46 V.22bis

LAST DIAL 555-1111 V.22

Table 3.1: Factory Default Configurations - Continued

FACTORY CONFIGURATION 0 PAGE 9

ERROR CORRECTION STATUS

TRANSMIT

12 0 CHARACTERS 12 0 BYTES 12 0 DATA FRAMES

13249 13261 RR FRAMES

128 DATA BYTES CURRENT MAXIMUM PER FRAME 128 DATA BYTES ABSOLUTE MAXIMUM PER FRAME

ERROR CORRECTION OFF

RECEIVE

0 0 RNR FRAMES

0 0 REJ FRAMES 0 0 ATTN FRAMES 0 0 ATTN ACK FRAMES

Type <enter> to continue:

FACTORY CONFIGURATION 0 PAGE 10

TEST COMMANDS

LOCAL ANALOG LOOP &T1 LAL WITH SELF TEST &T8 SEND DTMF TONE &T2n LOCAL DIGITAL LOOP &T3 REMOTE DIGITAL LOOP &T6 RDL WITH SELF TEST &T7 LAPM RDL WITH SELF

TEST

STOP TEST &T0

TEST TIMER 0 S18=0 LAL HOOK CTRL OFF @H0

63678 SECONDS

&T9

30 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Type <enter> to continue:

FACTORY CONFIGURATION 0 PAGE 11

LEASE LINE STATISTICS

LEASE LINE ACTIVE UADBU ACTIVE 0 SECONDS CONNECTION DOWN 62 SECONDS TOTAL 63741 SECONDS

LEASE LINE RETRAINS 0 UADBU CONNECTIONS 0

63679 SECONDS

Type <enter> to continue:

Table 3.1: Factory Default Configurations - Continued

FACTORY CONFIGURATION 0 PAGE 12

DIAL LINE STATISTICS

DIAL LINE ACTIVE 0 SECONDS

DIAL LINE IDLE 63743 SECONDS

TOTAL

ORIGINATE CONNECTS 0

ANSWER CONNECTS 0

ORIGINATE FAILURES 0

ANSWER FAILURES 0

DIAL LINE RETURNS 0

DIAL RETURN TIME 0 SECONDS

63743 SECONDS

Table 3.1: Factory Default Configurations - Continued

Factory Configuration Setting # 1

Default Factory Configuration Setting # 1

4-W LEASED LINE ORIGINATE MODE, AT&F1

Same as AT&F0 except:

1) COMMAND ECHO OFF E0

2) QUIET ON Q1

3) CONNECT MSG AT XMIT OK *C1

V.34bis Series Standalone & Rackmount Modems 31

Modes and Configurations

4) DTR FORCED &D0

5) DSR FORCED %D0

6) CARRIER OFF-XMIT &C2

7) CTS FORCED %C0

8) ANY CHAR ABORT OFF %B0

9) AUTO BAUD OFF @A0

10) DTE SPEED 9600 @D4

11) DATA BITS 7 @B7

12) PARITY EVEN @P4

13) LEASED LINE 4-WIRE &L2

14) DTE BUFF SIZE 256 &B0

15) GEN LOC FC NONE *LG0

16) CORRECTED MODE EXCLUSIV *M3

17) DATA COMPRESS OFF *E0

Table 3.1: Factory Default Configurations - Continued

Default Factory Configuration Setting # 2

4-W LEASED LINE ANSWER MODE, AT&F2

Same as AT&F0 except:

1) COMMAND ECHO OFF E0

2) QUIET ON Q1

3) CONNECT MSG AT XMIT OK *C1

4) DTR FORCED &D0

5) DSR FORCED %D0

6) CARRIER OFF-XMIT &C2

7) CTS FORCED %C0

8) ANY CHAR ABORT OFF %B0

9) AUTO BAUD OFF @A0

10) DTE SPEED 9600 @D4

11) DATA BITS 7 @B7

12) PARITY EVEN @P4

13) LEASED LINE 4-WIRE &L2

14) LEASED LN MODE ANSWER %O0

15) DTE BUFF SIZE 256 &B0

16) GEN LOC FC NONE *LG0

17) CORRECTED MODE EXCLUSIV *M3

18) DATA COMPRESS OFF *E0

32 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Table 3.1: Factory Default Configurations - Continued

Default Factory Configuration Setting # 3

4-W LEASED LINE ORIGINATE W/ UADBU, AT&F3

Same as AT&F0 except:

1) COMMAND ECHO OFF E0

2) QUIET ON Q1

3) CONNECT MSG AT XMIT OK *C1

4) DTR FORCED &D0

5) DSR FORCED %D0

6) CARRIER OFF-XMIT &C2

7) CTS FORCED %C0

8) ANY CHAR ABORT OFF %B0

9) AUTO BAUD OFF @A0

10) DTE SPEED 9600 @D4

11) DATA BITS 7 @B7

12) PARITY EVEN @P4

13) LEASED LINE 4-WIRE &L2

14) AUTO DIAL BKUP ON %U1

15) DIAL BKUP ALRM OFF %V0

16) LEASE LOOKBACK ON %L1

17) LOOKBACK TIMER 1 S56=1

18) DTE BUFF SIZE 256 &B0

19) GEN LOC FC NONE *LG0

20) CORRECTED MODE EXCLUSIV *M3

21) DATA COMPRESS OFF *E0

22) TEST TIMER 60 S18=60

V.34bis Series Standalone & Rackmount Modems 33

Modes and Configurations

Table 3.1: Factory Default Configurations - Continued

Default Factory Configuration Setting # 4

4-W LEASED LINE ANSWER W/ UADBU, AT&F4

Same as AT&F0 except:

1) COMMAND ECHO OFF E0

2) QUIET ON Q1

3) CONNECT MSG AT XMIT OK *C1

4) DTR FORCED &D0

5) DSR FORCED %D0

6) CARRIER OFF-XMIT &C2

7) CTS FORCED %C0

8) BAD SQ REDIAL SQ <= 7 &Q2

9) ANY CHAR ABORT OFF %B0

10) AUTO BAUD OFF @A0

11) DTE SPEED 9600 @D4

12) DATA BITS 7 @B7

13) PARITY EVEN @P4

14) LEASED LINE 4-WIRE &L2

15) LEASED LN MODE ANSWER %O0

16) AUTO DIAL BKUP ON %U1

17) LEASE LOOKBACK ON %L1

18) DTE BUFF SIZE 256 &B0

19) GEN LOC FC NONE *LG0

20) CORRECTED MODE EXCLUSIV *M3

21) DATA COMPRESS OFF *E0

22) TEST TIMER 60 S18=60

34 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Table 3.1: Factory Default Configurations - Continued

Factory Dial Configurations (1-4)

Factory Configuration Setting # 1

DTR, DSR CD FORCED AT&F1

Same as AT&F0 except:

1) DTR FORCED &D0

2) DSR FORCED %D0

3) CARRIER FORCED &C0

Factory Configuration Setting # 2

DTR, DSR CD FORCED AT&F2

Same as AT&F0 except:

1) DTR FORCED &D0

2) DSR FORCED %D0

3) CARRIER FORCED &C0

Factory Configuration Setting # 3

V.25bis HDLC/SDLC DIALER AT&F3

Same as AT&F0 except:

1) COMMAND ECHO OFF E0

2) CARRIER DTR-CARR &C3

3) DIALER TYPE V25 HDLC @V3

4) AUTO BAUD OFF @A0

5) ASYNC/SYNC SYNC &M1

6) GEN LOC FC NONE *LG0

7) CORRECTED MODE OFF *M1

Factory Configuration Setting # 4

V.25bis BISYNC DIALER AT&F4

Same as AT&F0 except:

1) COMMAND ECHO OFF E0

2) CARRIER DTR-CARR &C3

3) DIALER TYPE V25 BISY @V4

4) AUTO BAUD OFF @A0

5) ASYNC/SYNC SYNC &M1

6) GEN LOC FC NONE *LG0

7) CORRECTED MODE OFF *M1

V.34bis Series Standalone & Rackmount Modems 35

Modes and Configurations

36 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Dial-Up Operation

The modems can be used in the dial-up mode over the switched network. The following procedure will allow the user to quickly set up the modem for this common installation. The actual installation may be different from the example. In that case, the user must interpret the instructions to fit the application and the equipment used. The following procedure assumes the modem is set to the as shipped factory default configuration and an asynchronous terminal or PC running a terminal emulator program is provided.

Connect the modem to the terminal or PC using an RS-232 cable with pins 2, 3, 7 and 20 as the minimum connection. If the terminal or PC does not have a pin 20 (DTR) output, this signal can be forced on in the modem with the AT&D0&W <CR> command (<CR> = Carriage Return or ENTER). Some terminals or PCs require one or more of pins 5, 6 and 8 to operate. In that case, those pins will require connection and/or be forced on by the modem. See the AT commands in Table 6.1 + 6.2.

Set the terminal or PC speed to the highest speed of operation for communications. The DTR LED on the front panel modem should be illuminated. DTR must be on for an originating modem to connect or for an answering modem to answer a call.

TYPE: AT <CR> Modem responds: OK

If the modem does not respond, the other pins mentioned above may require connection and/or be forced on using the dip switches. The RS-232 cable may be mis-wired.

V.34bis Series Standalone & Rackmount Modems 37

Modes and Configurations

To Originate A Call

TYPE: ATDT<telephone number><CR>

The modem speaker will turn on. The following sounds will be heard: Dial tone. Touch tones as the modem dials. The ring signal or a busy signal. The answer tone from the remote modem. A series of harsh sounds as the modems "handshake" and "train".

The following messages, as a minimum, will be sent to the terminal:

BUSY or CONNECT 28800/V.42bis (or another speed), or CONNECT 19200/V.42bis (or another speed)

The speaker will turn off when the modems have finished the connection sequence (handshake and training) and the CD LED will illuminate.

If the telephone line is not of good quality the modem may redial, or the modem may operate at a lower speed and send a CONNECT message to the terminal or PC. If the terminal does not auto-baud, or the modem is not set for constant terminal speed, it will be necessary to change the terminal speed.

To Answer A Call:

Connect the equipment as above. TYPE: ATS0=1&W <CR> Modem responds: OK

The modem is now set to answer a call.

Note: This step may not be necessary. The modem is set for auto-

answer when shipped.

When a call comes in, the modem speaker will indicate the ringing.

The modem starts answering by sending the answer tone and starting the training sequence. A series of harsh sounds will be heard as the modems "handshake" and "train".

The speaker will turn off and the CD LED will illuminate on the modem front panel.

The modem is now connected with the far-end modem.

38 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Disconnecting From The Telephone Line

There are several ways to disconnect the modem from the telephone line to end a call:

> Press the DL/DIS switch on the front panel; RESET on the Fax Modem.

> Enter the escape code (+++) to return the modem to "AT" command

mode, then issue the ATH disconnect code from the DTE.

> If the modem is set to pay attention to DTR (AT&D2 is selected) turn off

DTR from the DTE or turn off the DTE. The modem will sense the Onto-Off transition of DTR and will disconnect from the line.

> The modem will automatically disconnect if the remote modem

disconnects.

> If a positive value is stored in S-Register 32, the modem will automatically

disconnect from the line if no data is transmitted, received or both (depending on the AT%In command) after the number of minutes specified in S-Register 32. Setting S-Register 32 to 0 disables the online inactivity timer (asynchronous mode only).

> Turn off or unplug the modem from the wall connection.

V.34bis Series Standalone & Rackmount Modems 39

Modes and Configurations

Busy-Out

Busy-Out is typically used in applications where multiple modems are used in a pooling environment and all incoming calls must be accounted for. If a modem goes bad, it may block all other modems "behind" it from receiving calls if not made busy. By enabling Busy-Out, the rotary group will "skip" the bad modem and go to the next available modem.

Conditions that will cause a modem "busy-out" to occur include:

1. The modem power-up self-test failed.

2. No +5v power supplied to the modem.

3. The modem rings 5 times without going off hook (this might occur if no DTR signal is present).

4. The modem answered 5 consecutive incoming calls without successfully connecting with the remote modem. This might occur if the DSP is defective or the phone line is connected to the wrong jack.

Note: 1) Jumpers J-12 and J-13 must be put in the ON position

2) When a modem busy-out condition occurs the DTR, DSR, CD,

CTS, SQ, ERR, TST and speed LEDs will flash continuously. Non-flashing LEDs will indicate the type of failure that has occurred:

DSR Ring without answer CD Failed power-up self-test CTS Failed answer handshake

40 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Phone Directory

AJ modems have a 100-number directory to store telephone numbers, name codes, passwords, attributes and call-linking codes. Information is entered in the directory with the AT&Zn command.

To display the phone number list, enter the AT&N command. This command displays the list of the phone numbers stored in non-volatile memory. The format of the display and an example follows:

# NAME PASSWORD PHONE # LINK CNF ATT

R 00 JOHN (408) 555-0000 04 D 01 FRANK B24E451 (408) 555-1111 N 02 HENRY Ad24rE (408) 555-2222 C 03 TOM (415) 555-3333 1 D 04 JOE (415) 555-3333 D

"#" The index of the stored phone number. This

number can range from 0 to 99.

"NAME" A 12-character ASCII string which is used for

dialing and answer security.

"PASSWORD" A 12-character ASCII string which is used for

answer security.

"PHONE NUMBER" A 25-character phone number, including

hyphens, parentheses, and dial modifiers.

"LINK" The index of the next stored number in a chain.

If an attempted call fails, the modem then dials the "linked" number. In the above example, suppose a call is made to John by typing "ATDS0". If John's phone is busy then the modem will automatically dial Joe.

"CNF" The stored configuration associated with this

phone number. This number can range from 0 to 9. In the above example, suppose a call is

made to Tom by typing "ATDS3". The

configuration stored in location 1 will be loaded before dialing the phone number.

V.34bis Series Standalone & Rackmount Modems 41

Modes and Configurations

"ATTR" The attributes associated with this stored

number. Valid attributes are:

A - Auto initiated call (DTR or front panel) D - Dial out location N - Pass through answer security location C - Call back answer security location S - Secured location (no display) P - Password transmit location

AT&Zn is used to store a phone number and associated information in nonvolatile memory at location "n". FORMAT:

AT&Zn:NAME:PASSWORD:PHONE:LINK:CNF:ATTR

Example:

AT&Z5:BILL:555-1234

stores the number "555-1234" at stored location 5 with the name

"BILL". The PASSWORD, LINK and CNF values are left blank to indicate that they are not used. The ATTR will default to "D".

Example:

AT&Z7:SUE:T3O68:555-4321:::C

stores the number "555-4321" at stored location 7 with the name

"SUE", password "T3O68". The LINK and CNF values are blank to indicate they are not used. ATTR is set to "C". An asterisk can be used when changing a value in an existing phone number record.

Example:

AT&Z4:*:*:*:*:N

will change the ATTR to "N" while leaving the remaining

information unchanged.

Example:

You want to make a long distance call using a credit card number

that makes the phone number longer than the standard 25 character limit:

AT&Z0:::510-555-1234-12345678+:1::D AT&Z1:::90123456:::D

In location 0 (AT&Z0), the "+" character at the end of the phone

number string indicates that more digits are to be added to the phone number. The LINK value of 1 is used to extend the phone

42 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

number value into the next directory listing (AT&Z1). The ATTR

is set to D.

Security

There are extensive security features in the AJ modems to prevent unauthorized access to the modem or attached equipment. The operation of these features allows different means of security to be utilized as best suited to the application. There are some precautions that should be taken to make access more difficult:

> Passwords should be protected on a "need to know" basis.

> Passwords should be changed frequently, especially if there is a

turnover of personnel.

> Passwords should be alphanumeric and not something easily guessed.

The most frequently used combination for the safes on the Manhattan Project was "238". If "TEST" or "JOE" were used for passwords, the most unsophisticated attempts would breach the security. Using a password such as "B45M9J3" would require a nearly impossible effort to achieve access.

Please do not forget the passwords. There is no

easy way to access the modem for that

circumstance and a return to the factory for repair

may be required.

Password Security

There are two types of passwords defined. The "operator" password is required to operate the modem. The "supervisor" password is required for higher level procedures such as to change options or to view memory. The operator defines the 2 passwords using the "%PO" and "%PS" commands described above.

Suppose that the following commands are entered:

AT%PO:USER:USER AT%PS:SUPER:SUPER AT%SC1

V.34bis Series Standalone & Rackmount Modems 43

Modes and Configurations

These commands set the operator password to be "USER" and the supervisor password to be "SUPER" (Please do not use these as passwords). In addition, the "AT" command security option has been enabled. The modem will now not allow any "AT" commands until the operator or supervisor password has been entered.

There are two ways to enter a password:

1. The password can be entered on the "AT" command line by enclosing it in parentheses. For example:

AT(USER)DT555-1111

2. The "AT" command line can be entered without the password and the modem will prompt for the password before executing the command. For example:

ATDT555-1111

Enter password:

The user now enters the correct password and the modem will then dial the number. The modem will not echo the characters as the password is entered.

The supervisor password can be entered in place of the operator password to allow complete access to all commands.

The password is entered only once. Once the

password has been entered it will remain in

effect until either the modem is reset or a

connection is dropped.

Passwords Provide These Controls:

• Allows access to AT dialer

• Dialing from memory, viewing stored numbers, changing stored

numbers

• Changing answerback, operator password, supervisor password

• Allows down-line loading

44 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Security Features

Pass-Through Access

The pass-through access security feature causes the answering modem to request a password from a calling modem. If the password entered at the calling modem matches one of the passwords stored in the answering modem telephone number directory with an "N" attribute, the calling modem will connect to the remote modem.

To set up pass-through access security:

1. Store the pass-through access security at the answering modem where the password field is the password and "N" is the attribute.

2. Enable pass-through access security in the answering modem with the

command AT%SA1.

When pass-through security is enabled, the modem will prompt callers for a password. If the caller enters the correct password, the modem will allow access to the DTE. If the password entry is incorrect, the modem will simply disconnect from the line.

Answer back

The answerback security feature function is like the pass-through access function except the operator does not type the password. The answering modem upon connection will request a password from the calling modem by sending a special character. The calling modem must respond with the correct answer back code within 2 seconds or it will be disconnected.

To set up answer back security:

Type AT&A:xxx..xxx:xxx..xxx<CR>, where xxx..xxx is the answer back code of up to 12 characters on both the calling and answering modems. When storing the answer back code it must be entered twice to ensure that it is saved correctly.

To disable answer back security: Type AT&A<CR>

V.34bis Series Standalone & Rackmount Modems 45

Modes and Configurations

Callback

Callback security protects data bases from unauthorized access by requesting a password and calling back the telephone number associated with that password. This security feature ensures that connections with incoming calls are made only with authorized locations.

When the callback security feature is enabled, the answering modem will request a password from the calling modem. If the password entered matches one of the passwords stored with a "C" attribute in the answering modem telephone number directory, the answering modem will disconnect from the telephone line and place a call back to the calling modem at the telephone number stored in the same memory location as the password. If the y command is set in the answering modem, when the call back telephone connection is made the initial answering modem again requests the password from the initial calling modem. The answering modem again compares the password from the calling modem with the stored password, and if correct then data transmission is allowed.

Setting up call back security involves storing the appropriate telephone number and password in memory with the "C" attribute and enabling call back security with the AT%SA1 command. The answering modem will have a random delay before dialing back the calling modem.

To set up call back security:

1. Store the call back number at the answering modem, where the password field is the password, and the number is the number of the dialing modem with the "CD" attributes.

2. Enable call back security in the answering modem with the command AT%SA1.

Callback security can be selected for any or all of the 100 memory locations. If more than one location is selected for call back, the modem searches all "C" designated locations for the password entered by the caller. If the password matches the password stored in one of those locations, the modem disconnects and places a call to the number stored in that location. If the password does not match the password with a "C" designated number, the modem drops the line.

Note:

1. CD and DSR pins on the RS-232 interface connector can be held on

during the callback by entering the command AT*S1.

2. The prompt "Password:" can be set so it will not be sent to the remote

modem by entering the command %SP0.

3. The modem password can be set to select the upper and low er case

by entering the command %SL1.

46 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Password Access

The automatic modem password security operation, particularly useful with synchronous terminals, provides an automatic exchange of the password between the modems before data transmission is allowed. When a phone number being dialed has an associated "P" attribute in the calling modem, the modem will wait for a password prompt to be received from the answering modem. If the calling modem receives the prompt in a few seconds it will respond with the "PASSWORD" stored with the dialed number and the "P" attribute. It will then allow data transmissions to proceed. If no prompt is received then it will allow transmissions when the timer expires in a few seconds. The answering modem for this type security will store the password expected, and when received it will proceed with data transmissions.

To set up automatic modem password access security:

1. Store the password in the "PASSWORD" field in both modems. Use the "P" attribute plus an “A" attribute (or a "D" attribute if dialing is by AT commands from an asynchronous terminal keyboard) in the calling modem, and the "N" attribute in the answering modem.

2. Enable the pass-through access security in the answering modem with the AT%SA1 command.

3. For additional security, the answer back security and/or a second password transmission may be implemented as in call back security. For this operation include the "C" attribute instead of the "N" attribute in the answering modem. See answer back and call back security operations. For the automatic operation to function with the front panel push button switch, the number dialed will be the first location in the phone list with an "A" attribute stored and the "P" attribute must be stored with the "A". If a second password request is used with call back security the AT%SB1 command is set in the answer modem, and it must also be set in the originate modem.

Examples:

1. Pass Through. The modem should prompt for name and password. If a correct name/password combination is entered then the connection is allowed to pass through.

AT%SA2 enable answer security AT%SP1 prompts turned on AT%ST0 allow 1 attempt AT%SL0 case sensitivity disabled AT&Z0:Joe:XXYZZ::::N store Joe

V.34bis Series Standalone & Rackmount Modems 47

Modes and Configurations

AT&Z0:Tom:XXZYY::::N store Tom

48 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

2. Call Back. The modem should prompt for name and password. If a correct name/password combination is entered then the modem should call back the user.

AT%SA2 enable answer security AT%SP1 prompts turned on AT%ST0 allow 1 attempt AT%SL0 case sensitivity disabled AT&Z0:Joe:XXYZZ:555-1111:::C store Joe AT&Z0:Tom:XXZYY:555-2222:::C store Tom

3. Call Back. The modem should prompt for password only. If an incorrect password is entered the modem should allow a second and third attempt. If a correct password is entered then the modem should call back the user.

AT%SA1 enable answer security AT%SP1 prompts turned on AT%ST1 allow 3 attempts AT%SL0 case sensitivity disabled AT&Z0:Joe:XXYZZ:555-1111:::C store Joe AT&Z0:Tom:XXZYY:555-2222:::C store Tom

4. Call Back. The modem should wait for password only, without prompting. The password will consist of lower and upper case characters. If a correct password is entered then the modem should call back the user.

AT%SA1 enable answer security AT%SP0 prompts turned off AT%ST0 allow 1 attempt AT%SL1 case sensitivity enabled AT&Z0:Joe:XXYZZ:555-1111:::C store Joe AT&Z0:Tom:XXZYY:555-2222:::C store Tom

V.34bis Series Standalone & Rackmount Modems 49

Modes and Configurations

Unattended Automatic Dial (Leased Line)

This feature is used to automatically originate and hold a connection during a specified time of day. If the connection is dropped it will automatically redial. For example, suppose you want the modem to automatically originate a call between 8 a.m. and 5 p.m. Monday through Friday and maintain the call within a specified time. Set the originate modem as follows:

ATS72=8S73=17 <CR>: Set window from 8 am - 5 p.m. weekdays

AT%Y1: Modem will disconnect from dial line at the end of window

AT%WD1: Originate only inside the window on weekdays

AT%U1: Dial enabled

ATS74=0S75=0: Set window for the weekend AT%WE1: Originate is disabled during the weekend AT%O1: Set to originate AT&L3: Unattended Automatic Dial Back-Up AT&D0: Force DTR on

Restricted Auto Answer (Leased Line)

This feature is used when the customer needs the modem to not answer after a specified time or to disconnect at a specified time. For example, suppose you want the modem to answer between 8 am and 5 p.m. Monday through Friday and disconnect at the end of the window. Set the answer modem as follows:

ATS72=8S73=17 <CR>: Set window from 8 am - 5 p.m. weekdays AT%Y1: Modem will disconnect from dial line at the end of window AT%WD1: Originate only inside the window on weekdays AT%U1: Answer enabled ATS74=0S75=0: Set window for the weekend AT%WE1: Originate is disabled during the weekend AT%O0: Set to Auto Answer AT&L3: Unattended Automatic Dial Back-Up only AT&D0: Force DTR on

50 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Automatic Answer Disable Timers

Another means of security is to control the time period when the modem is allowed to automatically answer an incoming call. There are two independent time intervals that can be set by the S-Registers, S90 and S91, to provide this type security. A range of 1 to 255 minutes is allowed for each register and a default setting of "0" disables the feature.

The setting of S90, Initial Auto Answer Disable Timer, provides a time interval from the time the DTR signal is forced on, or it is turned on by the DTE, to the time a ring signal is received. When this time interval expires the modem is disabled and will not auto answer a call until it is reset. To reset this timer press the DL/DIS switch twice, turn power off and then on, or issue the ATZ general reset command.

The setting of S91, Redial Auto Answer Disable Timer, provides an allowed time interval for a redial to occur. The time interval begins when a call is auto answered. If the modem is unable to connect because of an unacceptable signal, the timer allows a redial within the set time interval to be auto answered. The timer is reset when the modem answers a call but cannot complete a successful connection, the carrier is lost on an answered call that is disconnected, or when a "load saved configuration" operation is accomplished at a call disconnect. When the time expires the modem will not auto answer a call until it is reset.

V.34bis Series Standalone & Rackmount Modems 51

Modes and Configurations

Remote Configuration

The AJ Modems feature the down-line loading capability, which allows the controlling site to configure or reconfigure all modems in a network from a central location. All parameters in a modem's memory can be set remotely, including all information stored in the telephone number directory, all option settings, and the passwords. The AT&S command to the remote modem will provide the status screens of the remote modem to the local operator. The procedure to implement down-line loading is:

Set the modem for asynchronous mode (AT&M0).

Place a data call to the remote modem.

After the security password exchange, ENTER: CONTROL Z -three times

(in the same manner as "+++"). The modem will request the supervisor password.

ENTER: Supervisor Password. The modem will reply: OK

The operator at the local site now has control of the remote modem and may proceed to issue AT commands to the remote modem.

ENTER: AT commands - followed by a carriage return in the

usual manner.

When configuration operation is completed then: ENTER: ATO -to return to data mode.

Note: If the remote DTE is echoing the data, then the down-line load

character defined and stored in S38 of the remote modem must be different from the down-line load character defined and stored in S38 of the local modem. If these characters are not set different then the modems will both become locked in a down-line load condition.

52 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Error Correction and Data Compression

The AJ Modems support V.42 error correction LAPM protocol plus V.42bis data compression, and the Microcom Networking Protocol (MNP) Class 4 error correction plus MNP Class 5 data compression. These protocols are designed to be as transparent to the user as possible. These operations are discussed in the paragraphs that follow.

LAPM/MNP Error Correction Operation

LAPM/MNP provides error free communications and a boost in throughput. LAPM/MNP works by dividing data to be transmitted into segments, or frames. Each frame is transmitted with additional information so that the receiving modem can determine if an error occurred in the frame. If there is an error, the receiving modem requests the transmitting modem to retransmit the frame. A frame will be re-translated until it is received correctly, or the two modems decide that the telephone line is too degraded to allow acceptable transmission, and then hang up.

LAPM/MNP has its own flow control and break handling methods built into the protocol. This means that a LAPM/MNP communications link is always divided into three virtual links: a non-error corrected link between the DTE and modem, the LAPM/MNP error corrected link between the modems, and another non-error corrected link between the remote modem and remote device.

When the AT*Tn command is set for LAPM operation with n=2, or if LAPM is automatically operative when n=3, an error free connection will be established with an enhanced throughput. Errors in the data transmission will be detected and corrected with generally no noticeable effect to the operator. The LAPM operation begins with a detection phase of a time period determined by the setting of the S87 register (default time setting is

1.5 seconds).

During the detection phase the originating modem transmits a special character pattern and the answering modem responds with another special pattern. If the originating modem detects the response pattern within the detect time a LAPM connection is established. If the special pattern for LAPM is not detected the originating modem proceeds to a MNP connection if MNP is enabled. If the answering modem does not receive the special LAPM pattern from the originating modem within the detect time it will wait for a MNP frame for 3 seconds if MNP is enabled. Note: If the S87 register time is set to "0" the detection phase is bypassed and the modems proceed directly to a LAPM connection and the fallback to MNP will be disabled.

When an originating modem receives the appropriate carrier signal and then determines it is not a LAPM link, it then sends an MNP frame which

V.34bis Series Standalone & Rackmount Modems 53

Modes and Configurations

contains parameters concerning the level of MNP the modem can support. Upon receipt of this frame, the answering modem sends a similar frame, and the two modems negotiate to use the highest mutually supported level of MNP. If the answering modem does not send its initial frame, or sends non-MNP data, the originating modem will recognize that the answering modem does not support MNP. In such a case, the modem will connect in the non-MNP mode or will go on-hook, depending upon the command issued.

CAUTION: When the answering non-MNP modem passes the initial

MNP frame to a computer system it is likely to be unintelligible data to the system and provoke an undesired computer response. For such situations it may be necessary to not attempt to originate an MNP type call to the non-MNP modem, or to incorporate some action by the computer system to ignore the initial modem data containing the MNP frame.

Once a MNP link is formed, it is maintained until it is explicitly stopped with a command, the phone line becomes too noisy or degraded, or the modem goes on-hook.

The LAPM/MNP feature is enabled by the following procedure:

1) Enable a DTE flow control option:

The flow control function instructs a DTE to stop transmitting if the

modem buffers fill to capacity. Modem buffers tend to fill up rapidly whenever severe line conditions are encountered. Modems usually initiate the Stop Transmitting command by either dropping the Clear to Send (CTS) signal, or alternately by transmitting XOFF.

If the DTE responds to the CTS signal, it will stop transmitting when the CTS signal is not in the active state. For this condition use the command: AT*LG2

If the DTE responds to XON/XOFF characters, use the command: AT*LG1*RF1

2) Enable the LAPM/MNP operation enter: AT*Mn

The following chart summarizes the functions provided by setting of the AT*Mn command:

Command LAPM/MNP

Active Mode

AT*M0 no Direct mode AT*M1 no Normal AT*M2 maybe Automatic

54 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

AT*M3 yes Exclusive

To enable the LAPM/MNP connect message, enter: AT*V1 To check the status of the modem, enter: AT&Sn

n = 0 - Complete modem configuration display

Note: If the LAPM/MNP feature will be frequently utilized, it is important

that the AT&W command is entered to save the flow control and LAPM/MNP options set in non-volatile memory. As a result, the modem will power up with these options set, and it will not be necessary to reset these options in the event of power loss.

V.42bis and MNP Class 5 Data Compression

With a LAPM or a MNP connection this command offers the user the option of data compression in addition to error correction to increase throughput. If enabled, V.42bis compression will be active for a LAPM connection or MNP Class 5 data compression will be active for a MNP connection. These operations are entirely transparent to the user.

The AT*En Command for Data Compression

AT*En Where "n" is either "0" or "1" AT*E0 = Data compression is disabled AT*E1 = (Default) Modem will operate with V.42bis data compression if a LAPM link is established, or will operate with MNP Class 5 data compression if a MNP link is established.

The AT*En command enables or disables data compression when a LAPM or MNP connection is established. If AT*E1 is set, which is the default state, then the modem will attempt to operate with compression when it originates or answers a call. If AT*E0 is set then the modem will not provide compression. Most users will benefit from keeping the default setting of AT*E1 and using the data compression facility whenever available. If the data stream consists mainly of binary information, then the throughput will be increased by disabling compression with AT*E0.

The AT&S9 Status Display

To review the Error Correction Status Display discussed below, enter the AT&S9 command. Both a LAPM and a MNP Class 5 example and details are provided below.

V.34bis Series Standalone & Rackmount Modems 55

Modes and Configurations

Error Correction/Data Compression Status

LAPM Example

TRANSMIT RECEIVE

31135 53113 SECONDS 21250216 21250478 CHARACTERS 21250216 21250478 BYTES

60011 60011 DATA FRAMES

3 0 RNR FRAMES

19972 20000 RR FRAMES

1 0 REJ FRAMES 0 0 ATTN FRAMES 0 0 ATTN ACK FRAMES

256 DATA BYTES CURRENT MAXIMUM PER FRAME 256 DATA BYTES ABSOLUTE MAXIMUM PER FRAME LAPM, WINDOW SIZE 15 (TRANSMIT), 15 (RECEIVE) OK

or for V.42bis data compression with a LAPM connection:

V.42 BIS: BOTH DIRECTIONS, DICTIONARY SIZE 1024, STRING LENGTH 32 OK

The two columns are for transmit and receive statistics, respectively. The line labeled "Seconds" shows the number of seconds since the communications link was formed. In the above example, the modems were linked for 53113 seconds, or nearly 15 hours, when the status display was obtained.

56 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Characters (LAPM)

The line labeled "Characters" shows the number of characters sent and received by the modem since the link was formed.

Bytes (LAPM)

The line labeled "Bytes" shows the number of bytes sent and received by the modem since the link was formed. Without compression with a LAPM link the "Characters" and "Bytes" are the same. If compression is active then the "Bytes" sent and received are significantly less than the "Characters" sent and received as a result of the compression operation.

Data Frames (LAPM)

The line labeled "Data Frames" shows the number of LAPM data frames sent and received.

RNR Frames (LAPM)

The line labeled "RNR Frames" shows the number of "Receive Not Ready" frames sent and received. The modem sends a RNR frame when it is not ready to receive data frames.

RR Frames (LAPM)

The line labeled "RR Frames" shows the number of "Receive Ready" frames sent and received.

The modem sends a RR frame when it is ready to receive data frames.

REJ Frames (LAPM)

The line labeled "REJ Frames" shows the number of "Reject" frames sent and received. The modem sends a REJ frame when an error is detected that requires the remote modem to re-send a data frame.

Attn Frames (LAPM)

The line labeled "Attn Frames" shows the number of LAPM break signals sent and received.

V.34bis Series Standalone & Rackmount Modems 57

Modes and Configurations

Attn Ack Frames (LAPM)

The line labeled "Attn Ack Frames" shows the number of LAPM break signal acknowledgments sent and received. The next two lines show the maximum number of bytes allowed in a data frame. The first line shows the maximum number in effect at the time the status display was obtained. The second line shows the absolute maximum number agreed upon by the two modems when the LAPM link was formed. If there are many errors on the phone line then the maximum number of bytes per data frame is reduced to increase the throughput.

The last line with a LAPM error correction link indicates the LAPM connection plus the window size that the modems have agreed they can both buffer internally in the transmit and the receive directions. The last line with a V.42bis data compression link indicates the V.42bis connection plus the directions that compression is operative, the dictionary size and the string length.

Error Correction/Data Compression Status

MNP Example

TRANSMIT RECEIVE

31135 53113 SECONDS 21250216 21250478 CHARACTERS 15362453 21252634 BYTES

60011 60011 DATA FRAMES

3 0 DUP DATA FRAMES

19972 20000 DATA ACK FRAMES

1 0 ERRORS 0 0 ATTN FRAMES 0 0 ATTN ACK FRAMES

256 DATA BYTES CURRENT MAXIMUM PER FRAME 256 DATA BYTES ABSOLUTE MAXIMUM PER FRAME CLASS 5, WINDOW SIZE 8 OK

58 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

Characters

The line labeled "Characters" shows the number of uncompressed characters sent and received by the modem since the link was formed. The data throughput can be calculated by dividing the number of characters sent or received by the time.

Bytes

The line labeled "Bytes" shows the number of compressed bytes sent and received by the modem since the link was formed. The compression ratio, a measure of the compressibility of the data, may be obtained by dividing the number of uncompressed characters sent or received by the number of compressed bytes sent or received. In the example, the transmit compression ratio is 21250216 uncompressed characters divided by 15362453 compressed characters or 1.38. This means every data byte sent by the modem represented 1.38 bytes of user's data.

Data Frames

The line labeled "Data Frames" shows the number of MNP data frames sent and received.

Dup Data Frames

The line labeled "Dup Data Frames" shows the number of MNP data frames that were resent because of an error. In the example, the modem was notified of one error and resent three data frames because of it.

Data Ack Frames

The line labeled "Data Ack Frames" shows the number of MNP data acknowledge frames sent and received.

Errors

The line labeled "Errors'" shows the number of MNP data errors sent and received.

Attn Frames

The line labeled "Attn Frames" shows the number of MNP break signals sent and received.

V.34bis Series Standalone & Rackmount Modems 59

Modes and Configurations

Attn Ack Frames

The line labeled "Attn Ack Frames" shows the number of MNP break signal acknowledgments sent and received.

The next two lines show the maximum number of bytes allowed in a data frame. The first line shows the maximum number in effect at the time the status display was obtained. The second line shows the absolute maximum number agreed upon by the two modems when the MNP link was formed. If there are many errors on the phone line then the maximum number of bytes per data frame is reduced to increase the throughput.

The last line indicates the MNP Class 5 operation plus the number of data frames that the two modems have agreed they can both buffer internally.

MNP supports three classes of modem connection:

Class 1. A rarely seen, asynchronous, half duplex modem link (not

supported) Class 2. An asynchronous, full duplex modem link Class 3. A synchronous, full duplex link

"MNP Class 4" may be a misleading name because it is simply a set of optimizations which can be applied to any of the classes 1 through 3. The optimizations are less overhead in data and data acknowledgment frames, more user data allowed in data frames, and an algorithm that adjusts the amount of user data in each data frame for maximum throughput. If the MNP link is using these optimizations then the word "Optimized" will appear.

Similarly, "MNP Class 5" compression is another enhancement that can be applied to any of the classes 1 through 3 with or without the Class 4 enhancements. If the MNP link is using compression, then "Class 5" will appear.

60 V.34bis Series Standalone & Rackmount Modems

Modes and Configurations

V.34bis Series Standalone & Rackmount Modems 61

Front Panel Configurations

This section describes the front panel operation for the External and Rackmount modems. The front panel of the External modem has one push button switch and six red LEDs. Rackmount modems have 12 LEDs; 9 green and 3 red. The LEDs indicate the operating status of the modem.

External Front Panel Operation

ront Panel Button Functions

he front panel "Dial/Disconnect" switch, labeled DL/DIS has several

nctions as indicated below:

Command M•

Pressing DL/DIS momentarily in command mode initiates dialing of the first

telephone nu number with an "A" a switch is held so that DSR flas answer. If the switch is held for more than 4 seconds, the modem resets.

•

Leased Line

If the modem is set for

line training.

coming Ring • In

ressing the switch when an incoming ring is detected causes the modem

to answer the call.

•

On Line

P itch when online, disconnects the modem from the line.

ressing the sw

• Configuration Select

Holding DL/DIS for more than 4 seconds will initiate a hardware reset. If the switch is still pressed after the beeps, the modem will enter configuration mode. The front panel LEDs indicate which configuration

ode

mber stored in memory with the "A" attribute. If there is no

ttribute, the modem will manually originate. If the

hes twice, the modem will manually

leased line, pressing the switch will activate leased

V.34bis Series Standalone & Rackmount Modems 62

Leased Line Operation

the user can select as given on Table 4.2 (alternate AT commands are also shown).

V.34bis Series Standalone & Rackmount Modems 63

Leased Line Operation

Leased Line Modems

DTR DSR CD HS AT--

0. OFF OFF ON OFF User configuration "0" %M0

1. OFF ON OFF OFF User configuration "1" %M1

2. OFF %M2ON ON OFF User configuration "2"

3. ON OFF OFF OFF User configuration "3" %M3

4. ON OFF ON OFF User configuration "4" %M4

5. OFF OFF ON ON Dial configuration &F0

6. OFF iginate &F1ON OFF ON 4W Leased Line Or

7. OFF ON ON ON 4W Leased Line Answer &F2

8. ON OFF OFF ON 4W Leased Line Originate

w/UADBU

9. ON &F4OFF ON ON 4W Leased Line Answer

w/UADBU

Dial-Up Modems

DTR DSR CD HS AT--

0. OFF ON OFF User configuration "0" %M0OFF

1. OFF M1ON OFF OFF User configuration "1" %

2. OFF %M2ON ON OFF User configuration "2"

3. ON OFF OFF OFF User configuration "3" %M3

4. OFF ON OFF User configuration "4" %M4 ON

5. OFF OFF &F0ON ON Dial configuration

6. OFF ON OFF S

forced o

7. OFF ON ON Dial-up & DSR, CD, CTS

forced on

8. ON OFF OFF V.25bis HDLC/SDLC &F3ON

9. ON OFF ON V.25bis Bisy &F4ON nc

Each of the configuratio ay on for 2 seconds while the DL/DIS button is pressed. Releasing the button w configuration, and this configuration w r power up. Immediately after the power up test (after the beeps), the LEDs will indicate which configuration is loaded for 2 seconds.

Note: If the NVRAM (non-volatile RAM) is bad, holding the DL/DIS while

resetting the power will clear the NVRAM and load the modem with the dial up factory default.

Table 4.1: Configuration Modes

ns will st

ill be loaded afte

ill select the new

&F3

&F1ON Dial-up & DSR, CD, CT

&F2ON

64 V.34bis Series Standalone & Rackmount Modems

Leased Line Operation

DTR Data Terminal Ready - Lights when the modem receives

signal from the local DT forced on from the modem, otherwise the LED is (Also indicates a defective ROM during power up test.)

DSR Data Set Ready - Flashes when the ring signal is being

received on the telephone line or when responding to RDL. Lights when the answer tone is received. DSR flashing indicates originate mode in leased line. (Also indicates a defective RAM during pow

CD Carrier Detect - Lights when the carrier signal is detected on

the line or when forced on from the modem. (Also indicates a defective non-volatile memory during power up test.)

TD response to data transmitted by the Transmit Data - Flickers in

modem.

RD Receive Data- Flickers in response to data received by the

modem.

HS High Speed - Lights to indicate the modem operating speed.

Table 4.2 - LED Indicators

Modem Speed Blink Rate

t t t V.34

33,600 STEADY 31,200 16 28,800 15 26,400 14 24,000 13 21,600 12

19,200 8 16,800 7 14,400 6 12,000 5

E is online and ready for data, or when

flashing.

er up test.)

and Functions (External)

7,200 9

9,600 4 4,800 3 2,400 2 1,200 1

V.34bis Series Standalone & Rackmount Modems 65

Leased Line Operation

uring normal modem operation, the LEDs should light from left to right.

hat is, DTR should light first, indicating that the local

T followed by DSR, indicating a ring signal and answer tone; indicating presence of the data carrier.

Dialing Procedures NOT Using AT Commands

In addition n, the AJ F

a hese

x Modem offers several other ways to dial a telephone number. T methods can also be used when controlling the modem from a synchronous terminal:

Dialing via front panel DL/DIS switch Dialing via DTR control Manual dialing

Note: To abort a dialing procedure, simply strike any key on the DTE

to the "AT" command set for asynchronous operatio

keyboard or press DL/DIS.

Diali ng via Front Panel DL/DIS Switch:

DTE is online;

and then CD,

For asynchronous or

Press the DL/DIS s number stored in me manual originate if th attribute is not stored.

DTR Control Di

aling:

synchronous operation:

witch on the front panel. The modem dials the first

mory with the "A" attribute. The modem will switch to

e "A"

Turn the DTR circui ed in memory with the the "A" attribute i

Manual Dialing

t ON. The modem dials the first number stor

attribute. The modem will switch to manual originate if

"A"

t stored.

s no

Connect the telephon the rear panel of the be called and listen your call. Momentar handset and proceed

e cable from the telephone set to the TEL SET jack on

modem. Dial the telephone number of the modem to

for the high pitched tone from the modem answering

ily press the DIAL switch, then hang up the telephone

with the data transmission.

66 V.34bis Series Standalone & Rackmount Modems

Leased Line Operation

Rackmount Front Panel Operations

Figure 4

ORIG

RDL

ANS

CTS

DTR/

PWR

LAL

DSR

.1: Rackmount Modem Front Panel

DISC

ERR

FBS

DIAL

TST

HIGH

MED

LOW

The front panel of the AJ Rackmount has six touch switches and 12 LEDs. The LEDs indicate th operating status of the modem and are described in Table 4.2. The front pictorial above. The All switch actuation a

e panel switches, the LEDs and their labels are shown functions of the switches are given in Table 4.3 below. re momentary unless otherwise noted.

Note: T

he front panel may be disabled by setting Bit 2 of S-Register

S102 to a “1

Table 4.3 - Rackmount Front Panel Functions

LAL Pressing this switch initiates the Local Analog

Loopback Test when off-line. Pressing this switch initiates the Local Digital Loopback Test when on-line. Pressing this switch a second time terminates the test. These tests do not use the internal test generator and comparator.

RDL this switch initiates the Remote Digital Pressing

Loopback Test when on-line. Pressing this switch a second time terminates the test. This test does not use the internal test generator and comparator.

ORIG/ANS

DISC

V.34bis Series Standalone & Rackmount Modems 67

When off-line, momentarily pressing this switch causes the modem to go off-hook and operate in the originate mode, and pressing the switch for more than 2 seconds causes the modem to operate in the answer mode. If this switch is pressed when a ring signal is being received, the modem will be forced offhook in the answer mode. If the modem is on-line and this switch is pressed, the operating configuration will be displayed by the appropriate LED. Pressing the switch a second time will terminate the configuration d

isplay.

When on-line, momentarily pressing the switch causes the modem to disconnect from

the telephone line in dial up or leased line operation, and returns the modem to the Command Mode. Holding this switch for more than 4 seconds causes the modem to disconnect and then perform a hardware reset (same as the power reset). Immediately after the power-up test and the three beeps, the appropriate LED will indicate for 2 seconds the configuration that is loaded.

Leased Line Operation

Table 4.3 - Rackmount Front Panel Functions

BS (Fall Back Speed) Rackmount Only

If the switch remains pressed during this 2 second interval, the modem will be in the Config Mode and then may be toggled betw Factory Configuration Select Modes by the use of the DIAL switch. A subsequent pressing of the DISC switch will cause the modem to return to the Idle Mode. The modem will then operate with the selected configuration.

If the modem is on-line in momoarily pressing this switc

ment h cause the

to return to the Leased Lin

dem e . Pressing

mo arily again will cause a di connec

ment s t from the

lea ne.

sed li

If t odem is off-line and the leased

he m option is

sel , momentarily pressing the DISC sw

ected itch will

cause the modem to return to the Leased Line Mode. When of sion will toggle the speed

from 33600 to 31200 to 28800 21600 to 19200 to 16800 to 14400 etc. depending the ed by other setting

f-line, each depres

telephone transmission speeds allow

a dial backup operation then

to to 24000 to

uration Select

een the User and

will

Mode

26400

W in the Configuration Select Mode each

hen depressi sw the configur 4 as indic by the LEDs. This cy with the current configuration setting.

on of the FBS

ations 0,1,2,3 a

cle will begin

itch steps through

DIAL When in normal dial operation pressing this switch

initiates the dialing of the first stored telephone number with the "A" attribute. When connected in leased line operation it initiates a manual dial backup operation. When the modem is in the Configuration Select Mode this switch toggles the modem between the User and the Factory Configurations.

NOTE: When in dial backup operation pressing this switch with turn off the beeper.

68 V.34bis Series Standalone & Rackmount Modems

Leased Line Operation

SUMMARY:

igurationsConf

Commands

Selecting a st active for Rac illuminate follo

Selected Config -- LED Indicators ON AT

User Configuration "0" HI-f,MED-f,LO-f and DTR %M0

User Configuration "1" HI-f,MED-f,LO-f and DSR %M1

User Configuration "2" HI-f,MED-f,LO-f and CD %M2

User Configuration "3" HI-f,MED-f,LO-f and CTS %M3

User Configuration "4" HI-f,MED-f,LO-f and SQ %M4

Dial Configuration HI-f,LO-f and DTR &F0

4-W Leased Originate

4-W Leased Line Answer HI-f,LO-f and CD &F2

V.25bis HDL HI-f,LO-f and CTS &F3 C/SDLC

V.25bis Bisync HI-f,LO-f and SQ &F4 (f = flashing)

, Indications, & Alternate AT

ored configuration and visually verifying which configuration is

kmount units. During power-up you will see the TEST light

wed by a set of LEDs as listed below.

Commands

Line HI-f,LO-f and DSR &F1

V.34bis Series Standalone & Rackmount Modems 69

Leased Line Operation

LED Function: DTR

DSR

CTS

TD RD

ERR

TST Test - Lights when the modem is in a test mode from a local

70 V.34bis Series Standalone & Rackmount Modems

DatDTa Terminal Ready - Lights when the modem receives a

on signal from the local DTE indicating the terminal

devi

ce is ready for data communication, or when the DTR

sign

al is forced on by the modem; otherwise this LED is

flas

hing when in the Idle Mode. When in the Configuration Select Mode this LED indicates "Configuration 0". (Also indicates a defective ROM at the end of a failed power up test or a reset.)

Data Set Ready rece m the telephone li an RDL test is in

ived fro

progress from the local/remote Lights steady when

answer t When in

the one is received. the Configuration Select Mode this LED indicates "Configuration 1". (Also indicates a defective RAM at t of a failed power up test

reset.) icates in lea

or a DSR flashing ind sed line originate mode.

Carrier Detect - Lights when the modem detects an acceptable carrier signal on the n the CD is forced

y the m

on b odem. When in the Configuration Select Mode

LED ind "Configuration 2". (Also indicates a

this icates defective non-volatile memory a failed power up test or a reset.)

Clear to Send - Lights w he modem can s

delays and handshake operations including MNP

time

tiations ted. Also t

nego have been comple he RTS signal from the DTE must be on, or must the modem. When in the Config. Mode this ates "Configuration 3".

Signal Quality - Lights when the modem has detec signal of acceptable quality for data transmission to proceed. When in the Configura “Configuration 4".

Transmit Data - Flickers in response to data transmitted.

Receive Data - Flickers in response to data received by the modem.

Error - Lights momentarily each time an error is detected in an MNP controlled data transmission. When a loopback test is performed using the internal test generator and comparator, the ERR LED will flash when an error is detected.

or a remote input. Continuous flashing indicates the modem

- Flashes w g signal is being

hen the rin

ne or when

modem.

he end

line or whe

at the end of

hen t end data, i.e.

be forced on by

LED indic

tion Select Mode this LED indicates

ted a

Leased Line Operation

LED Function:

is in a dial backup operation.

HI, MED, LO

MED

Table 4.4: Rackmount Front

All speed lights off indicate 300 baud.

During normal modem operation, the LEDs should light from left to right. That is, DTR should light first, indicating that the local DTE is online; followed by DSR, indicating a ring signal and answer tone; and then CD, indicating presence of the data carrier.

High, Medium, Low - The HI, MED and LO LEDs provide a visual indication of the speed at which the modem is currently operating or set to. Each LED has two operating modes, on steady and flashing. This allows fo displaying one speeds.

On Steady

1 Blink

2 Blinks

3 Blinks

4 Blinks

5 Blinks

On Steady

1 Blink

2 Blinks

3 Blinks

On Steady

1 Blink

2 Blinks

3 Blinks

of the 12 most common operating

33600 bps

31200 bps 28800 bps

26400

bps

24000 bps

21600 bps 19200 bps

16800 bps 14400 bps

12000 bps 9600 bps

7200 bps 4800 bps

2400 bps

Panel LED Indicators

V.34bis Series Standalone & Rackmount Modems 71

Leased Line Operation

Rackmount Procedures Not Using AT Commands

In addition to the "AT" command set for asynchronous dialing operati AJ Rackmount modem These methods can be a synchronous terminal, but they

Dialing via front panel DIAL switch. Dialing via DTR control. Manual dialing.

Note: To abort a dialing procedure, simply strike any key on the DTE

keyboard or press DISC.

Dialing via Front Panel DIAL Switch:

Press the DIAL switch on the front panel. The modem dials the first number stored in memory with the "A" attribute. The modem w originate if the "A" attribute is not stored.

DTR Control Dialing:

Turn the DT memory with the "A" attribute. The modem will switch to manual originate if the "A" attribute is not stored.

R circuit on. The modem dials the first number stored in

Manual Dialing:

Connect the telephone cable from the telephone set to the DIAL 1 jack on the rear panel of the modem. Dial the telephone number of the modem to be called and listen for the high pitched tone from the modem answering your call. Momentarily handset and proceed with the data transmission.

offers other ways to dial a telephone number.

particularly useful when controlling the modem from

apply also for an asynchronous terminal.

ill switch to manual

press the DIAL switch, then hang up the telephone

on, the

72 V.34bis Series Standalone & Rackmount Modems

Leased Line Operation

(Optional)

Modems configured with leased line operation will operate on 2 or 4-Wire le

ased lines. Most 2-Wire leased lines are actually 4-Wire leased lines with 4-Wire to 2-Wire adapters installed. p

refer

red because the installation is less cluttered and has no signal

degradation from the adapter.

When the modems are connected on a leased line, one modem is d

esignated as the origi

modem. The configurations for each are slightly different.

The following procedure will allow the user to quickly set up the modem for t

he most common 4-Wire installation, assuming the modem is set default. An assumed attached.

onnect the leased line to the leased line jack on the rear of the chassis. Connect e mode to the terminal a the minimum connection.

nd 20 as If the terminal does not have a pin 20

( put, this signal can be forced on in the modem with the AT

DTR) out &D0

CR> (

< command <CR> = Carriage Return or enter). Some terminals require one or more of pins 5, 6, and 8 to operate. In that case, those pins

ill require connection and/or be forced on by

w the modem. See the AT commands.

See Section 6 for further information on Auto Baud Rate Detection and setting fixed DTE spe communications. The DTR must be ON for an originating modem to connect or for an answering modem to answer a call.

TYPE: AT <CR> Modem responds: OK

If the modem does not respond, t require connection and/or be forced on using the dip switches as described in Chapter 2. The RS-232 cable may be mis-wired.

asynchronous terminal or a PC internal emulator mode is

th m using a RS-232 cable with pins 2, 3, 7,

nating modem and the other as the answering

ed. Set the terminal speed to the highest speed for

A 4-Wire leased line connection is

he other pins mentioned above may

to factory

V.34bis Series Standalone & Rackmount Modems 73

Leased Line Operation

For the Originating Modem:

TYPE: AT&D&L2%O1&WZ <CR>

Note: DSR LED will flash continuously to indicate the modem is in ORIGINATE mode.

For the Answering Modem:

TYPE: AT&D&L2%O0&WZ <CR>

The modems will then go through a tr each other. The CTS, CD, SQ illuminate. The speaker will be off.

The modems will stay connected until there is a severe degrada leased line or a power failure. When t improves, the modems will automatically

Commands:

The following commands affect

AT&Ln n = 0: No leased line n = 1: 2-W leased line n = 2: 4-W leased line n = 3: Unattended Automatic Dial Back-Up (UADBU) only AT%XLn n (5-8) Leased line transmit level. (-10 dBm through -16 dBm

in 2 dBm steps for n=5 through 8.)

Set one modem to be in LEASED LINE ORIGINATE and the other in LEASED LINE ANSWER utilizing the AT%On command. Save options to non-volatile memory.

Press DIS on both modems. The modems should establish the connection in 30 seconds. If the leased line fails, the modems will try to retrain. If dial back up is not enabled, the modem will wait for the leased line to be restored and then start training to reconnect.

the leased line operation.

aining sequence and connect with

and speed LEDs of both modems will

he power returns or the leased line

reconnect.

tion in the

74 V.34bis Series Standalone & Rackmount Modems

Leased Line Operation

Unattended Automatic Dial Back-Up

These mo Automatic s ill automatica

o that it w lly on the switched network if

he leased line fa ADBU clock-calendar control so the

modems will not nnece p calls.

order to confi mode up. The follo g additio ommands are necessary:

or the Orig ng M

STORE A PHONE DI

TYPE: AT&L %L1% W <CR>

or the Ans g M

TYPE: AT&L2%L1%U1&

The modems now set or is disconnected. In order to limit with the comm the modem to

ADBU can also trolle

U HIGH on pin 14 will force the nected to the leased line to make a dial back up ll. (AT% ust be entered for this to work.)

dems e the implement the Unattended

includ

Dial B (UAD he modem can be configured

ack-Up

ils. U

make u ssary dial back u

gure the ms for UADBU, start with the leased line set-

win nal c

capability to BU) feature. T

restore the data link

operates under

inati odem:

TEL E N ATTRIBUTE. (See

EPHON

RECT PERA ommands.

ORY O

2 U1&

UMBER WITH AN "A"

TION, page 40 for AT c

werin odem:

W <CR>

are to g line degrades

a d bel

nds liste

"lo " at th

okback

be con d by pin 14 of the RS-232 interface. A logical

ca U0 m

o into UADBU when the leased

UADBU to certain times, set the limits

ow. The %Ln command must be enabled for

e leased line to see if it is restored.

modem con

V.34bis Series Standalone & Rackmount Modems 75

Leased Line Operation

The following commands affe and UADBU operation.

AT&Ln n = 0: No leased line n = 1: 2-W leased line n = 2: 4-W leased line n = 3: Unattended Automatic Dial Back-Up only AT%XLn n (5-8) Leased line transmit level AT%On n = 0: Leased line answer mode n = 1: Leased line originate mode AT%Un n = 0: Dial back up disabled n = 1: Dial back up enabled AT%WDn n = 0: Dial back up is enabled outside the window

n = 1: Dial back up is enabled inside the window on

ATS72=n n (0-23) Weekday window starting hour ATS73=n n (0-23) Weekday window ending hour AT%WEn Dial back up is enabled outside the window

n = 0:

n = 1: Dial back up is enabled inside the window on

ATS74=n n (0-23) Weekend window starting hour ATS75=n n (0-23) Weekend window ending hour AT%Yn n = 0: Modem stays connected to dial line at end of

n = 1: Modem will disconnect from dial line at end

AT%Ln n = 0: Leased line lookback disabled n = 1: Leased line lookback enabled

Table 5.1: UADBU Commands

ct the leased line

on weekdays

weekdays

on weekends

weekends

window

of window

76 V.34bis Series Standalone & Rackmount Modems

Leased Line Operation

Window Setup

OUTSIDE INSIDE OUTSIDE

Start Window End Window

WEEKDAY: S72=n WEEKEND: S74=n

S73=n S75=n

EXAMPLE: SETUP THE MODEM FOR UADBU BETWEEN 8 A.M. AND 5 P.M. during weekdays (Monday th w

eekend, the modem will automatically disconnect at the end of the

rough Friday). Do not dial during the

window. The connection type on the leased line is V.32.

ATS72=

8S73=17<cr>:

Set window from 8 a.m. - 5 p.m. (weekdays).

AT%Y1:

Modem will disconnect from dial line

at end of window.

AT%WD1:

ial back up is enabled inside the window on weekdays.

AT%U1:

Dial back up enabled.

ATS74=0S75=0:

Set window for weekend.

AT%WE1:

Dial back up is enabled inside the window on weekend, and since the duration of the window is zero, UADBU is disabled during weekend.

Note: Optional on Leased Line only.

V.34bis Series Standalone & Rackmount Modems 77

Leased Line Operation

ookback

When leased line lookback option is enabled the lookback timer S-Register 56 should be enabled.

ATS56=n Wait for n (0-255) minutes interval, then lookback at the leased line for 10 seconds; n=0 is constant lookback.

When auto-lookback is enabled following will happen: The modem, detecting that the leased line is restored, to retrain on the leased li modem wi takes over

will attempt ne. If the training fails, the

ll go back t . From the

o the dial-up line. This will happen once before S56

n on, the modem will wait for the time period stored in

S56 before attempting a lookback.

Set one modem to be LEASED LINE ANSW

in LEASED LINE ORIGINATE and the other to be in

ER (AT%On command). Save options to non-volatile

memory.

Press "DL/DIS" on oth modems. The modems should establish the connection in 30 seco initiated the stored leased lin configuration fa

ils, the modems w

nds. Each time a leased line connection is

defaults will be reloaded. This allows the dial back up

settings to be different from the leased line. If the leased line

ill try to retrain.

If dial back up is not enabled, the modem will wait for the leased line to be back in operation, then start training and establish the connection.

If dial back up is enabled, the modems will try to train on the leased line for 15 seconds. If not successful, the originate mode modem w phone number with the "A" attribute, and the answering modem should answer the ring and connect. The speaker will emit a tone every second to announce the leased line is down, but it can be turned off by pressing DL/DIS button momentarily or by the AT%V0 command.

If leased line lookback is enabled, the originate modem will transmit a 0 dBm pilot tone every two seconds to the leased line and wait for response from the answering modem.

The answering modem, when detecting the pilot tone, will send back a 1/2 second tone, hold the dial line, go back to the leased line and start training. The originate modem, when detecting a tone from remote modem, will hold the dial line, go back to the leased line and start training for 15 seconds.

If the training is not successful, both modems will switch back to the dial line and re-establish the connection.

78 V.34bis Series Standalone & Rackmount Modems

and S56 is set greater than zero, the

ill dial the

Leased Line Operation

Additional Dial Back-Up Lookback Features

Using S-Registers 77 and 78, two additional features can be invoked for the dial back up operations. The first is to have the modem make the dial back up call and maintain the dial connection for five minutes before attempting the lookback action. The second is to have the modem test the dial back up link once every twenty-four hours. These features are controlled by the S77 and S78 registers as follows:

S77 = 0 Disables these features S77 = 25 Enables the five minute hold on the dial connection

before attempting a lookback.

For both of the above S77 settings the S78 setting is not relevant.

77 = This is the hour clock setting for the test of the dial

1 through 24 S

back up link with 24 considered as midnight.

S78 = 0 through 59 This is the minute setting for the test o

up link.

The dial back up link test will establish a link with both carriers detected and then will hang-up and return to lease line operation. If this test is successful pin 25 of the EIA connector will toggle from OFF to ON then OFF with an

terval of 500 milli-seconds. For this indication the dip switch settings must

in include S2-3 in the OFF position an

d S2-4 in the ON position.

f the dial back

V.34bis Series Standalone & Rackmount Modems 79

Leased Line Operation

Manual Dial Back-Up Operation

As an alternative to automatic dial back up the manual dial ba

bility provides full control over the operation of the modem on dial-up

capa

. To initiate manual dial back up operation proceed with the initiation of

lines a dial call from a number in storage. The modem will proceed to dial the number stored with an "A" attribute and connect (see Section 4 for detailed front panel operation). A beeper sound will be heard indicating the modem is in a dial back up operation.

To return the modems to le from ection and the

the dial conn

initiate

the traini If the leased line is "good" the data

co re-established.

nne

ction will be

Note: ial back up can only be initiated from the origi

Manual d nating

modem.

ng operation.

Change Real Time a

mands

Com

T%T (string d (see Table 6.2) is used to change

The A , as below) comman the tim of the real tim

e and date e clock. The format of the command is:

AT% ss:mm-dd

Thh:mm: -yy

Note: The Clock Calendar o

models, but is not availabl

ased line operation, proceed with a disconnect

modem will return to the leased line and

nd Date with AT

ption is available for the Leased Line

e for the Dial-Up models.

ck up

80 V.34bis Series Standalone & Rackmount Modems

AT and V.25bis Command Sets

Chapter 6 provides listings of he AT commands for ready reference follow with the full details for a

ed by tables ll commands.

Table 6.1: AT Commands by Function

General and Setup

AT Attention Code

Sr=n Set Register

Z Reset (Recall User Configuration)

*Hn Busy Out &Fn Factory Configuration Load &Wn Write Active Configuration to Non-Volatile Memory %Mn Load Non-Volatile Memory Bank

%T Store Time and Date

@Ln Load Default Options

Data Format and Rate

&Mn Async/Sync Mode Select @An Auto Baud Rate Detect @Bn Data Bits @Cn Constant DTE Rate @Dn DTE Speed @Mn Modem Speed @Pn DTE Parity Sn DTE Stop Bits

Dialing and Answering

A Answer D Dial Command

DSn Dial Stored Telephone Number Hn Hook Switch Control Ln Speaker Volume Mn Speaker Control On Return to the Online State

P Pulse Dial R Originate Call in Answer Mode

Sn Dial Stored Number

T Touchtone Dial

&Gn Guard Tone Selection &Pn Pulse Dial Make/Break Ratio Select &Qn Signal Quality Redial &Zn Store Phone Number %An Adaptive Dial %Bn Any Character Abort @Vn Dialer Selection

V.34bis Series Standalone & Rackmount Modems 81

AT and V.25bis Command Sets

Table 6.1: AT Commands by Function

EIA Control

&Cn CD EIA Control &Dn DTR EIA Control &Rn RTS/RTR EIA Control &Xn Synchronous Transmit Clock Source %Cn CTS EIA Control %Dn DSR EIA Control %EAn EIA Control of LAL (Local Analog Loopback) %ERn l Loopback) EIA Control of RDL (Remote Digita %ESn EIA Speed Control *RPn RT S Polarity *Sn DSR and CD Control During Call Back

Error Correc pression tion and Data Com

$$$ Switch to LAPM/MNP Link

&S9 Status Display Example

*An Adaptive Packet Size *Bn Block/Stream Mode *En Enable or Disable Compression *Gn LAPM/MNP Error Alarm *Mn Operating Modes

*O Originate LAPM/MNP Link

*Pn Maximum Packet Size

*RS Reset Error Statistics

*Tn Select Protocol - V.42(LAPM) or MNP

*U Accept LAPM/MNP Link

*Y Switch to LAPM/MNP Link

*Z Switch to Normal Link from MNP

Flow Control

82 V.34bis Series Standalone & Rackmount Modems

AT and V.25bis Command Sets

Table 6.1: AT Commands by Function

Command Mode at Transmit Break

*Dn

*KAn ransmit Break Clear Transmit Buffer at T *KBn Clear Transmit Buffer at Receive Break *KCn Clear Receive Buffer at Transmit Break *KDn Clear Receive Buffer at Receive Break

*KT Break Type

*LBn Local Overflow Bell *LGn Generate Local Flow Control *LRn Respond to Local Flow Control *RBn Remote Overflow Bell *RFn Filter Receive Flow Control *RGn Generate Remote Flow Control *RKn Pass Receive Break *RRn Respond to Remote Flow Control *XFn Filter Transmit Flow Control *XKn Pass Transmit Break

&B3 DTE Buffer Size

Leased Line and Dial Back-Up

&Ln Leased Line or Dial-Up Select %Ln Leased Line Lookback %On Leased Line - Originate or Answer %Un Auto Dial Back-Up %Vn Auto Dial Back-Up Alarm %WDn Weekday Window %WEn Weekend Window %XLn ansmit Level Leased Line Tr %Yn Window End Disconnect

Online Operations

Bn ty Bell/CCITT Protocol Compatibili Yn Long Space Disconnect %Fn Auto Fall Back %Hn " Operations V.22 bis and V.21/103 "HUNT %In mer Inactivity Ti %Qn Loss of Carrier Redial %Rn Automatic Retrain %XDn Dial Line Transmit Level @Tn Trellis Encoding @Xn Transmit Equalizer @Fn Online Speed Change

Security

V.34bis Series Standalone & Rackmount Modems 83

AT and V.25bis Command Sets

Table 6.1: AT Commands by Function

&A Answ

%PO Store Operator Password

%PS Store Supervisor Password

%SAn Answer Password Security %SBn Second Password Prompt in Call Back %SCn "AT" Command Security %SDn Remote Configuration Security %SLn Password Upper/Lower Case Sensitivity %SPn Prompt Security

%SSn Rack Control

%STn Password Attempts Allowed %SWn n-Volatile Write Security No

Test

Cn Transmit Carrier Control

In Request Product Firmware Revision & ROM Checksum

&Tn Test Mode Selection @Hn On/Off Hook in LAL @Rn Respond to RDL Request

Visual Responses

En Command Echo Qn Quiet Command (Enable Responses)

Sr? Read "S"-Register

Vn Result Codes as Word or Digit Xn Extended or Basic Result Code Set

&N Display Phone Number List

&Sn Status Display *Cn Connect Message Output Control *Nn Modem/DTE Speed in Connect Message *Vn Extended Result Codes

er Back Storage

84 V.34bis Series Standalone & Rackmount Modems

AT and V.25bis Command Sets

Table 6.2: Details

AT Command Descriptions

The expanded The followi the A

T commands and settings is displayed by sending AT&S to the

modem. T command is always followed by the <CR>.

AT Attention Code FORMAT: AT [other commands]

Begin eac mmand.

nd must begin each command line, any

Note: Since the AT comma

A Answer FORMAT: ATA

Causes t em to go off-hook immediately, answer an incoming tele call, and wait for a carrier si

phone gnal.

: Dial (D)

Note This command can be used in conjunction with the

Bn BELL/CCITT Protocol Compatibility FORMAT: ATBn

n = 0 - CCITT protocol (V.22 mode 2 or V.22bis) is selected.

AT command set offers the user a wide range of capabilities.

ng is a list and description of all "AT" commands. A summary of

he AT

h command line with AT co

command issued singly (except A/ command.

he mod

ommand to switch from voice to da

c ta communication, this command should not be used for auto answ

) must be preceded by this

er.

12A or 201) is selected. n = 1 - (Default) Bell protocol (103, 2

Note: Data rate is determined by the communication data rate at which

last AT command was issued.

Cn Transmit Carrier Control FORMAT: ATCn

Turns transmit carrier off for test purposes.

n = 0 - Carrier transmit OFF n = 1 - (Default) Carrier transmit ON

Dn Dial Command FORMAT: ATD%n

V.34bis Series Standalone & Rackmount Modems 85

AT and V.25bis Command Sets

Table 6.2: Details

mposed of dial modifiers and telephone Note: %n represents a string co

number digits.

Dial Modifiers

P - Pulse Dial

R - Reverse Mode

Sn - Dial Stored Number

T - Touch Tone Dial (Default)

W - Wait for Dial Tone

@ - Wait for Quiet Answer

% - Abort current call and proceed to the next phone number

! - Flash

, - Pause

; - Return to Command State

X - Dial in auto reliable mode, LAPM/MNP or non PM/MNP

Y - Dial in exclusive mode, LAPM/MNP only

Z - Dial in normal mode, no LAPM/MNP

$Name- Dial by name - Dia

name matches the

Notes: The X, Y, and Z commands override the current co

setting, but only for this connection

DSn Dial Stored Tel. Number FORMAT: ATDSn

Note: When telephone numbers are dialed from memory the redials as

defined by register S55

En Command Echo FORMAT: ATEn

n = 0 - Echo off

n = 1 - (Default) Echo on

Hn Hook Switch Control FORMAT: ATHn

86 V.34bis Series Standalone & Rackmount Modems

ls number stored at location

name entered after the $ sy

will proceed. The default is 0.

where the stored

mbol.

nfiguration

AT and V.25bis Command Sets

Table 6.2: Details

n = 0 - On hook (hang up) n = 1 - Off hook

In R oduct Firmware Revision equest Pr

and ROM Checksum

n = 0 - Requests product firmware revision n = 1 - Requests firmware checksum n = 2 - Tests firmware checksum; report s “OK" if correct n = 3 - Requests product type and EPROM part number n = 4 - Requests library information n = 5 - Requests manufacturing feature list device ID’s n = 6 - Requests programmable n - Requests power-up self-test r = 7 esults n = 8 - Requests power-up configuration

Ln Speaker Volume

n = 0 - Low volume n = 1 - Low volume n = 2 - (Default) Medium volume n = 3 - High volume

Mn Speaker Control

n = 0 - Speaker disabled n = 1 - Default) Speaker off when carrier received n = 2 - Speaker always on n = 3 - Speaker off when carrier received or dialing

On Return to the Online State

n = 0 - Return on-line n = 1 - Retrain for V.32terbo, V.32bis, V.32 and V.22bis n = 2 - Fallback to next lower speed n = 3 - Fall forward to next higher speed

Note: Option 2 and 3 will function only if on-line speed change has be

enabled (AT@F1).

Pn ulse Dial P FORMAT: ATDPn

FORMAT: ATIn

FORMAT: ATLn

FORMAT: ATMn

FORMAT: ATOn

V.34bis Series Standalone & Rackmount Modems 87

AT and V.25bis Command Sets

Table 6.2: Details

Note: When the modem is first po

The Pulse command can be entered alone (AT default to pulse dialing until the next command.

Qn Quiet Command (Enable Responses) FORMAT: ATQn

n = 0 - (Default) Messages or result codes are displayed.

n = 1 - Messages or result codes are not displayed.

n = 2 - Messages or result codes are displayed in originate

mode, but not in answer mode.

R Originate Call in Answer Mode FORMAT: ATDnR

Note: The R command must be the last dial string character. When the R command is used, no call progress reports are sent to the DTE.

When the R command is issued, the modem sends the answer tone, even if it receives a busy signal.

Sr? Read "S"-Register FORMAT: ATSr?

wered on, it is set for touchtone dialing.

P) to switch the

modem reset or touchtone

Sr=n Set Register FORMAT: ATSr=n

The S-registers are registers that hold modem configuration parameters.

Sn Dial Stored Number FORMAT: ATDSn

T Touchtone Dial FORMAT: ATDTsss-sss-ssss

Note: When the modem is powered on, it is set for touchtone dialing.

Vn Result Codes as Word/Digits FORMAT: ATVn

88 V.34bis Series Standalone & Rackmount Modems

AT and V.25bis Command Sets

Table 6.2: Details

= 0 - n Selects digit codes

n = 1 - (Default) Selects word codes

Xn Extended/Basic Result Co et de S FORMAT: ATXn

Allows the selection of extended or the basic set of result codes.

n = 0 - Selects basic set. n = 1 - Selects extended set. n = 2 - Selects extended set with dial tone detection. n = 3 - Selects extended set with tion. busy detec n = 4 - (Default) Selects extende e set with dial tone

dete l detection.

ction and busy signa

The X command allows the selection CODES or the basic set. T modem “blind d command settings determine result co If *Vn is set to n=1 then the L data rate. This indic modem-to-m s

peed is ind data rate and the maxi s. If *Nn is se speed is the DTE dat f RESULT C definitions for the ATXn

he selection of the results code set also determines if the

ials” or if it listens for a dial tone before dialing. Two other

some of the des that will be displayed.

APM or MNP functions are indicated after the

ation of LAPM/V42BIS/MNP/MNP5 is related only to the

odem communication link. set to n=0 then only the

icated. If *Nn is set to n= speed is the modem

mum is 33,600 bp t to n=1 the indicated

a rate. A listing o ODES follows with n

command.

d result cod

of extended sets of RESULT

If *Vn is

0 the indicated

V.34bis Series Standalone & Rackmount Modems 89

AT and V.25bis Command Sets

Table 6.2: Details - Results Codes

"AT" Dialer V.25 bis Dialer

0 OK VAL 1 CONNECT CNX 2 RING INC 3 NO CARRIER --4 ERROR INV 5 CONNECT 1200 CNX 1200 6 NO DIAL TONE CFI ND 7 BUSY CFI ET 8 NO ANSWER CFI NT 9 CONNECT 7200 CNX 7200

10 CONNECT 2400 CNX 2400 11 CONNECT 4800 CNX 4800 12 CONNECT 9600 CNX 9600 13 CONNECT 12000 CNX 12000 14 CONNECT 14400 CNX 14400 15 DELAYED DLC 16 NUMBER FORBIDDEN CFI FC 17 NUMBER NOT STORED CFI NS 18 MODEM BUSY CFI CB 19 ABORT CFI AB

20 CONNECT 19200 CNX 19200 21 CONNECT 38400 CNX 38400 22 CONNECT 57600 CNX 57600 23 CONNECT 115200 CNX 115200 24 CONNECT 16800 CNX 16800 25 CONNECT 24000 CNX 24000 26 CONNECT 28800 CNX 28800 27 ERROR CNX 28 ERROR INV CU 29 ERROR INV MS

30 ERROR INV PS 31 ERROR INV PV 32 NO CARRIER CFI RT 33 BLACKLIST FULL CFI BF 34 CONNECT 1200T/75R CNX 1200T/75R 35 CONNECT 75T/1200R CNX 75T/1200R 36 FLASH FLASH 37 CONNECT 21600 CNX 21600 38 CONNECT 25400 CNX 26400 40 CONNECT 300/MNP CNX 300/MNP

90 V.34bis Series Standalone & Rackmount Modems

AT and V.25bis Command Sets

Table 6.2: Details - Results Codes

"AT" Dialer V.25 bis Dialer

41 CONNECT 7200/MNP CNX 7200/MNP 42 CONNECT 1200/MNP CNX 1200/MNP 43 CONNECT 2400/MNP CNX 2400/MNP 44 CONNECT 4800/MNP CNX 4800/MNP 45 CONNECT 9600/MNP CNX 9600/MNP 46 CONNECT 12000/MNP CNX 12000/MNP 47 CONNECT 14400/MNP CNX 14400/MNP 48 CONNECT 19200/MNP CNX 19200/MNP 49 CONNECT 38400/MNP CNX 38400/MNP

50 CONNECT 300/MNP5 CNX 300/MNP5 51 CONNECT 7200/MNP5 CNX 7200/MNP5 52 CONNECT 1200/MNP5 CNX 1200/MNP5 53 CONNECT 2400/MNP5 CNX 2400/MNP5 54 CONNECT 4800/MNP5 CNX 4800/MNP5 55 CONNECT 9600/MNP5 CNX 9600/MNP5 56 CONNECT 12000/MNP5 CNX 12000/MNP5 57 CONNECT 14400/MNP5 CNX 14400/MNP5 58 CONNECT 19200/MNP5 CNX 19200/MNP5 59 CONNECT 38400/MNP5 CNX 38400/MNP5

60 CONNECT 300/LAPM CNX 300/LAPM 61 CONNECT 7200/LAPM CNX 7200/LAPM 62 CONNECT 1200/LAPM CNX 1200/LAPM 63 CONNECT 2400/LAPM CNX 2400/LAPM 64 CONNECT 4800/LAPM CNX 4800/LAPM 65 CONNECT 9600/LAPM CNX 9600/LAPM 66 CONNECT 12000/LAPM CNX 12000/LAPM 67 CONNECT 14400/LAPM CNX 14400/LAPM 68 CONNECT 19200/LAPM NX 19200/LAPM C 69 CONNECT 38400/LAPM CNX 38400/LAPM

70 CONNECT 300/V42BIS CNX 300/V42BIS 71 CONNECT 7200/V42BIS CNX 7200/V42BIS 72 CONNECT 1200/V42BIS CNX 1200/V42BIS 73 CONNECT 2400/V42BIS CNX 2400/V42BIS 74 CONNECT 4800/V42BIS CNX 4800/V42BIS 75 CONNECT 9600/V42BIS CNX 9600/V42BIS 76 CONNECT 12000/V42BIS CNX 12000/V42BIS 77 CONNECT 14400/V42BIS CNX 14400/V42BIS 78 CONNECT 19200/V42BIS CNX 19200/V42BIS 79 CONNECT 38400/V42BIS CNX 38400/V42BIS 80 CONNECT 57600/MNP CNX 57600/MNP 81 CONNECT 115200/MNP CNX 115200/MNP

V.34bis Series Standalone & Rackmount Modems 91

AT and V.25bis Command Sets

Table 6.2: Details - Results Codes

"AT" Dialer V.25 bis Dialer

82 CONNECT CNX 57600/MNP 57600/MNP5 5 83 CONNECT CNX 115200/MNP5 115200/MNP5 84 CONNECT 57600/LAPM CNX 57600/LAPM 85 CONNECT 115200/LAPM CNX 115200/LAPM 86 CONNECT 57600/V42BIS CNX 57600/V42BIS 87 CONNECT 00/V42B 115200/V42BIS CNX 1152 IS 88 CONNECT 16800/MNP CNX 16800/MNP 89 CO NECT 24000/MNP CNX 24000/MNP N

90 CONNECT CNX 28800/MNP 28800/MNP 91 CONNECT CNX 16800/MNP5 16800/MNP5 92 CONNECT P5 24000/MNP5 CNX 24000/MN 93 CONNECT 28800/MNP5 CNX 28800/MNP5 94 CONNECT 16800/LAPM CNX 16800/LAPM 95 CONNECT 24000/LAPM 24000/LAPM CNX 96 CONNECT 28800/LAPM CNX 28800/LAPM 97 CONNECT 16800/V42BIS CNX 16800/V42BIS 98 CONNECT 24000/V42BIS CNX 24000/V42BIS 99 CONNECT 28800/V42BIS CNX 28800/V42BIS

100 CONNECT 21600/MNP CNX 21600/MNP 101 CO MNP CNX 26400/MNP NNECT 26400/ 102 CONNECT 21600/MNP5 CNX 21600/MNP5 103 CONNECT 26400/MNP5 CNX 26400/MNP5 104 CONNECT 21600/LAPM CNX 21600/LAPM 105 CONNECT 26400/LAPM CNX 26400/LAPM 106 CONNECT 21600/V42BIS CNX 21600/V42BIS 107 CONNECT IS CNX 26400/V42BIS 26400/V42B

110 CONNECT 31200/LAPM CNX 31200/LAPM 111 CONNECT 31200/V42BIS CNX 31200/V42BIS 112 CONNECT 33600/MNP CNX 33600/MNP 113 CONNECT 33600/MNP5 CNX 33600/MNP5 114 CONNECT 33600/LAPM CNX 33600/LAPM 115 CONNECT 33600/V42BIS CNX 33600/V42BIS

92 V.34bis Series Standalone & Rackmount Modems

AT and V.25bis Command Sets

Table 6.2: Details Continued

Yn Long Space Disconnect

n = 0 - (Default) Long space disconnect disabled n = 1 - Long space disconnect enabled

Z Reset (Recall User Configuration)

Note: Resetting the modem clears the command buffer, so commands

after the Z in the command line are ignored, and a subsequent A/ command will be invalid.

$$$ Switch to LAPM/MNP Link

Example: Current Status: CONNECT 9600 Enter: (1 second pause) $$$ (1 second pause)

New Status: CONNECT 9600/MNP5

&A Answer Back

Storage

Note: Storing an answer back sequence enable

function. If the modem is used in answe modem must have the answer back sequen disconnected.

&Bn DTE Buffer Size

n = 0 - 256 bytes n = 1 - 1K bytes (Default)

&Cn CD EIA Control

Forces CD (Carrier Detect) signal on to the connected DTE.

n = 0 - CD signal forced on. n = 1 - (Default) CD off. CD turns on if carrier is detected. n = 2 - CD off in command mode. CD off during mod

CD turns on when modem can pass full duplex data.

n = 3 - CD follows DTR in command mode. CD off during modem

handshake. CD turns on if carrier is detected.

n = 4 - CD follows DTR in command mode. CD off du

handshake. CD turns on

data.

FORMAT: AT&A:ssssssssssss:ssssssssssss

s the answer back

r mode, the originate

ce or it will be

when modem can pass full duplex

FORMAT: ATYn

FORMAT: ATZ

FORMAT: AT&Bn

FORMAT: AT&Cn

em handshake.

ring modem

Note: If n=2 or 4 then CD will not turn on until after all security

processing and MNP negotiations have been completed

V.34bis Series Standalone & Rackmount Modems 93

AT and V.25bis Command Sets

Table 6.2: Details Continued

&Dn DTR EIA Control

n - DTR EIA signal forced on = 0 n = 1 - CCITT 108/1 operation. n = 2 - (Default) CCITT 108/2 operation.

&Fn Factory Configuration Load

n = 0 - 4 configuration number (see Chapter 3)

&Gn Guard Tone Selection

n = 0 - (Default) No guard tones are generated n1 - 550 Hz tone gen = erated n = 2 - 1800 Hz tone generated

&Ln Leased Line or Dial-up Select

(Leased Line Modems)

n = 0 - (Default) Selects a dial-up connection n = 1 - Selects a 2-Wire leased line connection n = 2 - Selects a 4-Wire leased line connection n = 3 - Selects UADBU connection without leased line

Note: Connection can be established with synchronous or

asynchronous operation

&Mn Async/Sync Mode Select

n = 0 - (Default) Selects async operation when on-line. n = 1 - Selects sync operation for data mode (ext. only)

&N Display Phone Number List &Pn Pulse Dial Make/Break Ratio

n = 0 - (Default) 39% make; 61% break (U.S. setting) n = 1 - 33% make; 67% break (Brit. Common. setting)

&Qn Signal Quality Redial

n = 0 - (Default) signal quality redial feature disabled. n = 1 - Redial if signal quality ≤ 8 n = 2 - Redial if signal quality ≤ 7

The number of redials, 0 through 8, is determined by the setting of Sregister S55 (default S55=0).

FORMAT: AT&Dn

FORMAT: AT&Fn

FORMAT: AT&Gn

FORMAT: AT&Ln

FORMAT: AT&Mn

FORMAT: AT&N

FORMAT: AT&Pn

FORMAT: AT&Qn

94 V.34bis Series Standalone & Rackmount Modems

AT and V.25bis Command Sets

Table 6.2: Details Continued

&Rn RTS/RTR EIA Control FORMAT: AT&Rn

n = 0 - (Default) RTS/RTR is forced on.

n = 1 - RTS/ lied RTR is supp by the DTE.

n = 2 - RTS/ lied E. When RTS is off, the

&Sn Status D splay i FORMAT: AT&Sn

n = 0 - Display each page of configuration (n=1 to n=10).

n = 1 - and inteVisual display rface signal configurations.

n = 2 - eDialing, answ ring and online configurations.

n = 3 - Format/data rate and leased line configurations.

n = 4 - Flow control and break handling.

n = 5 - LAPM/MNP error correction and action commands.

n = 6 - Security information.

n = 7 - Action commands.

n = 8 - Connect status display.

RTR is supp by the DT

remote modem will turn CD off to simulate a half-duplex

ection.

conn

n = 9 - LAPM/MNP error correction statistics.

n =10 - Test commands.

n =11 - Leased Line Statistics.

n =12 - Dial Line Statistics.

V.34bis Series Standalone & Rackmount Modems 95

AT and V.25bis Command Sets

Table 6.2: Details Continued

&S9 Status Display Example

TRANSMIT RECEIVE

53113 SECONDS

21250216 21250478 CHARACTERS

15362453 15362634 BYTES

60011 60011 DATA FRAMES

3 0 DUP DATA FRAMES

(RNR FRAMES for LAPM operation)

19972 20000 DATA ACK FRAMES

(RR FRAMES for LAPM operation)

1 0 ERRORS

(REJ FRAMES for LAPM operation)

FORMAT: AT&S9

0 0 ATTN FRAMES

0 0 ATTN ACK FRAMES

256 DATA BYTES CURRENT MAXIMUM PER FRAME

256 DAT IMUM PER FRAME A BYTES ABSOLUTE MAX

CLASS 5, WINDOW SIZE 8

Or for a LAPM error correction connection the last line is:

LAPM, WINDOW SIZE 15 (TRANSMIT), 15 (RECEIVE)

Or for a V.42 bis compression connection the last line is:

V.42 BIS: BOTH DIRECTIONS, DICTIONARY SIZE 1024, STRING LENGTH 32

96 V.34bis Series Standalone & Rackmount Modems

CXR V.34bis series Operation And Installation Manual

Specifications and Main Features

Frequently Asked Questions

User Manual