Multi-Tech Systems BA-Series manual Modem Dials But Cannot Make a Connection

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MultiModemBA User Guide

The Modem Dials But Cannot Make a Connection

There can be several reasons the modem fails to make a connection. Possibilities include

lack of a physical connection to the telephone line.

a wrong dial tone.

a busy signal.

a wrong number.

no modem at the other end.

a faulty modem, computer, or software at the other end.

incompatibility between modems.

You can narrow the list of possibilities by using extended result codes. To enable them, enter ATV1X4 and press ENTER while in terminal mode, or include V1X4 in the modem’s initialization string. When you dial again, the modem will report the call’s progress.

If the modem reports NO DIALTONE, check that the modem’s telephone line cable is connected to both the modem’s LINE jack (not the PHONE jack) and the telephone wall jack. If the cable looks secure, try replacing it. If that doesn’t work, the problem may be in your building’s telephone installation. To test the building installation, plug a telephone into your modem’s telephone wall jack and listen for a dial tone. If you hear a dial tone, your modem may be installed behind a company phone system (PBX) with an internal dial tone that sounds different from the normal dial tone. In that case, the modem may not recognize the dial tone and may treat it as an error. Check your PBX manual to see if you can change the internal dial tone; if you can’t, change your modem’s initialization string to replace X4 with X3, which will cause the modem to ignore dial tones.

If the modem reports BUSY, the other number may be busy, in which case you should try again later, or it may indicate that you have failed to add a 9, prefix to the phone number if you must dial 9 for an outside line.

If you must dial 9 to get an outside line, the easiest way to dial it automatically is to include it in the modem’s dial prefix, e.g., ATDT9,. Note the comma, which inserts a pause before the number is dialed. By inserting 9, into the dial prefix, you do not have to include it in each directory entry in the terminal.

To change the dial prefix in Windows Terminal, select Settings, Modem Commands. To change it in Windows 95 HyperTerminal, select Call, Connect from the menu bar, click Dialing Properties, and type 9 in the local and long distance boxes in How I Dial from This Location.

If the modem reports NO ANSWER, the other system has failed to go off-hook, or you might have dialed a wrong number. Check the number.

If the modem reports NO CARRIER, the phone was answered at the other end, but no connection was made. You might have dialed a wrong number, and a person answered instead of a computer, or you might have dialed the correct number but the other computer or software was turned off or faulty. Check the number and try again, or try calling another system to make sure your modem is working. Also, try calling the number on your telephone. If you hear harsh sounds, then another modem is answering the call, and the modems may be having problems negotiating because of modem incompatibilities or line noise. Try connecting at a lower speed.

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Contents User Guide User Guide Record of RevisionsContents Index 106 Introduction and Description How To Use This Manual IntroductionModem Features Callback and Remote ConfigurationDIP-Switches Warranty, Service & Technical Support1 2834 Series Features Fax FeaturesTechnical Specifications Power Modem LED Indicators MT2834 LED DisplayControls on PC Board Installation and Connection What is in Your Modem Package? InstallationSafety Warnings Installation ProcedureInstallation and Connection Step ProcedureInstalling Data Communications Software MultiModemBA/BAI ConnectionsSoftware Configuration and Modem Basics Configuring Your Software Configuring Software for Your ModemPC Initialization Strings AT &F X4 S0=0 MChanging Default Parameters Configuring Software for Your ComputerConfiguring Software for the Remote System Other ParametersTerminal Emulation File Transfer ProtocolsCommand Mode AT Command Editing Functional ModesSummary of AT Commands Command ModeStore Modem Configure Data Result Codes Multi-Tech Result CodesStandard AT Result Codes Dialing Commands Dialing Action Commands Dial Command DContinuous Redial not used in BAI a or Dialing a Stored Number NDial Modifier Commands DTR Dialing $DVoice/Data Dialing $VD Pulse or Tone Dial P TReturn to Command Mode After Dial Command Execution Reverse the Mode of Operation RSet Pulse Dial Ratios &P Automatic Pauses in DialingPhone Number Memory Commands Flash On HookCalling Card Detect Tones $ Quiet Answer @Configuration and Default Storage Commands Number Linking NNListing Numbers Stored in Memory L Loading Factory Defaults &F Modem Reset ZAsync/Sync Mode Switching &M Unix Uucp Spoofing $SPCommand Response Result Code Commands Echo Command Mode Characters EResult Codes Enable/Disable and No Response Answer Q Result Codes Multi-Tech or Standard AT &QPhone Line Conditioning Commands Result Codes Basic and Extended and Call Progress SelectionGuard Tones Not Used in BAI Models &G Enable/Disable Trelis Coded Modulation #T Fallback Modes When On-Line #FBell/V.21 Tone Phone Line Monitoring Speaker M7 RS-232C Interface Control Commands Enable/Disable Lowspeed Fast Connect $FCCleardown at Disconnect &CD Auto Speed Detect #AData Terminal Ready Control &D CTS Control &RData Set Ready Control &S CTS/RTS Interaction Control &RFError Correction Commands Enable/Disable Auto Reliable Fallback Character $F Auto-Reliable Buffering $AFlow Control Commands Error Correction/300bps $ERetransmit Count $R Hardware Flow Control &E4 Xon/Xoff Flow Control &E5Xon/Xoff Pass-Through &E7 Normal Mode Modem Flow Control On &E11 Send Xon/Xoff Characters #XHewlett-Packard ENQ/ACK Pacing &E9 Terminal/Computer Initiated Pacing &E13Normal/Auto-Reliable/Reliable Mode Commands Xon/Xoff Pass-Through CommandsEnq/Ack Pacing Commands Parity Selection #PSpeed Conversion Commands Speed Conversion $BAModem Baud Rate $MB Serial Port Baud Rate $SB Immediate Action Commands Force Answer Mode a Off Hook HLine Probe Commands Exiting Command Mode, Going Back On-Line OEnable/Disable Reading of Line Probe Information Commands Format of Line Probe Graph or Table CommandsRegisters Number of Rings Until Modem Answers Rings Which Have OccurredEscape Code Character Return CharacterTime for Carrier Abort Timer Line Feed CharacterBackspace Character Wait Time for Dial ToneS10 Carrier Loss Disconnect Delay Time S13 Remote Configuration Escape CharacterCarrier Detect Response Time S11 Tone Dialing Tone Spacing and DurationS15 Callback Time Delay S16 Callback AttemptsS17 Changing Break Time S24 PBX/CBX Disconnect Drop Time for DSR/CTS/CDS26 Failed Password Attempts S29 Local Inactivity TimerS30 Inactivity Timer S32 Time Elapse for Escape SequenceReading and Assigning S-Register Values S36 Time Between DTR Inactive and Modem Off-HookS37 Time Between DTR Active and Modem On-Hook S48 Program V.34bis Connect Speeds 2834 Series onlyAT Command and S-Register Summary Examples of Assigning ValuesExamples of Reading Values Callback Security and Remote Configuration Callback Feature Description Remote Configuration DescriptionTo change your Remote Configuration feature status To turn your modems Callback Security feature on and offTo set parity of the password/message prompt AT#DB2CR or AT#DB1CR Remote Configuration Procedures Callback Security and Remote ConfigurationCallback Operational Sequence Procedures Remote Configuration Operation Procedures StepProcedureRemote Configuration and Callback Security AT Commands Callback Security Enable/DisableChange Login Password AT#I=yyyyyyyyyyCRRemote Configuration/Callback Security S-Registers Local Inactivity Timer S29 DIP-Switch Settings DIP-Switch Option Settings PC BoardSwitch #4 AS/400 Mode Synchronous Mode/Leased Line/Dial-UP DIP-Switch SettingsMultiModemBA User Guide = Down Down Speaker Volume Control Switch #16 Reserved for Future UseRecording Option Configurations Switch Function Position EffectDIP Switches #13-14 DIP Switches #15-16Warranty, Service and Tech Support Multi-Tech Systems, Inc. Warranty & Repairs Policies Warranty, Service, and Technical SupportOnline Warranty Registration Repair Procedures for International DistributorsReplacement Parts Technical SupportInternet Sites Country TelephoneAppendixes Upgrade Overview Appendix a Upgrading Your Modem’s FirmwareDownload the Upgrade File Upgrade the Modem’s Firmware Appendix B Troubleshooting None of the LEDs Light When the Modem Is OnModem Does Not Respond to Commands Appendix B Troubleshooting Modem Dials But Cannot Make a Connection Modem Cannot Connect When Answering Modem Disconnects While On-lineFile Transfer Is Slower Than It Should Be Am Losing DataAm Getting Garbage Characters on the Monitor Apendix C AT Command Summary Appendix C AT Command SummaryCommand Values Description MultiModemBA User Guide Command Values Description SN d$Fn RF n $SBn Break Atcr Callback Security/Remote Configuration Command Summary Password Command Summary Command Description #Ixxxxxxxxxx#Syyyyyyyyyy 25bis Commands Delayed and Forbidden Numbers Appendix D V.25bis Operation25bis Operation 25bis Mode AT Commands 25bis DIP-Switches25bis Set-Up and Initialization Appendix D V.25bis Operation25bis AT Commands Enable/Disable V.25bis Mode $V CommandChange Serial Baud Rate CSP Command 25bis Responses Result CodesDial Phone Number Provided CRN Command Listing Delayed Phone Numbers RLD CommandListing Forbidden Phone Number RLF Command Disregard or Connect to Incoming Calls DIC or CIC CommandDTR Dialing $D Command ITU V.25bis Country Specific InformationItaly SwitzerlandAppendix E MultiModemBA Cables Austria FranceBelgium SingaporeAppendix E MultiModemBA Cables Figure E-1. RS232 Cable IBM PCAppendix F Regulatory Information FCC Part FCC Part 68 TelecomAppendix F Regulatory Information Industry CanadaCanadian Limitations Notice 104EMC, Safety, and R&TTE Directive Compliance International Modem Restrictions105 Index 106Index 107PBX/CBX Disconnect Drop Time for DSR/CTS/CD53 108109