Multi-Tech Systems MT3334ZDXV owner manual Slow File Transfer, Losing Data

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2 - Installation

Slow File Transfer

You may have an older UART. For best throughput, install a 16550AFN UART or a Multi-Tech ISI serial port card.

If you are running under Windows 3.1 and have a 16550AFN UART, you must replace the Windows serial driver, COMM.DRV, to take full advantage of the UART’s speed.

If you are using a slow transfer protocol, such as Xmodem or Kermit, try Zmodem or Ymodem/G instead.

Is your line noisy? If there is static on your line, the modem has to resend many blocks of data to insure accuracy. You must have a clean line for maximum speed.

Are you downloading a compressed file with MNP 5 hardware compression enabled? Since hardware data compression cannot compress a file already compressed by an archiving program, the transfer can be marginally slower with data compression enabled.

Try entering the &V (View Parameters) command, making a screen print of the diagnostics listing, and checking for parameters that may be unacceptable.

Losing Data

If you are using data compression and a high speed serial port, set the serial port baud rate to four times the data rate.

Your UART may not be reliable at serial port speeds over 9600 bps or 19,200 bps. Turn off data compression, reset your serial port speed to a lower rate, or replace your serial port with a faster one.

Make sure the flow control method you selected in software matches the method selected in the modem.

If you are running under Windows 3.1 and have a 16550AFN UART, you may need to turn on the 16550’s data buffers and/or replace the Windows serial driver, COMM.DRV.

Try entering the &V (View Parameters) command, making a screen print of the diagnostics listing, and checking for parameters that may be unacceptable.

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Contents Page Revision Description PatentsContents Index Computer Introduction and Description RequirementsSerial Cable Telephone LineCommunications Software Product FeaturesData About this Manual Installation and ConnectionFax Voice Model MT3334ZDXV onlyTesting Your Modem AT Commands, S-Registers and Result CodesService, Warranty & Technical Support AppendicesSafety Warnings Installation IntroductionInstallation Process Page MultiModemZDX Connections Front Panel LED IndicatorsInstallation Is Your MultiModemZDX Ready for Use? Simple Operations Operating Your MultiModemZDXRemote Configuration AT&Fcr Software ConfigurationHardware/Software Confirmation MultiModemZDX Configuration ConfirmationNone of the LEDs Light When the Modem Is On TroubleshootingModem Does Not Respond to Commands Installation Modem Dials But Cannot Make Connection Installation Modem Disconnects While Online Modem Cannot Connect When AnsweringLosing Data Slow File TransferGarbage Characters on the Monitor AT Commands, S-Registers Result Codes Command Summary Dial Echo Command Mode CharactersDial string modifiers Monitor Speaker Mode Monitor Speaker VolumeEcho Online Data Characters On-Hook/Off-Hook ControlEnable/Disable Result Codes Return Online to Data ModeModulation Handshake = n Set Register ValueResult Code Selection Modem ResetLong Space Disconnect Data Carrier Detect DCD ControlCommunications Mode Load Factory Default SettingsData Terminal Ready DTR Control 22bis Guard Tone ControlATDS=n \K n Set Break Control \N n Error Correction Mode Selection\V n Protocol Result Code Data Compression ControlSerial Port Baud Rate Modem Baud RateRegisters S10 Register Unit Seconds Range 255 Default DescriptionS28 S11S30 S35S42 S37S43 S89 S48Terse Verbose Description DelayedLocal Analog Loopback Test Modem Testing Local Analog Loopback Test/V.54 LoopDigital Loopback Test/V.54 Loop 2 Local/Manual Digital Loopback Testlocal/manual Digital Loopback Test/V.54 Loop 2 Remote/AutoDigital Loopback Test remote/automatic Limited Warranty Tech Support On-line Warranty RegistrationRecording Modem Information Service Logging on to the Multi-Tech BBS About the Multi-Tech BBS No Longer AvailableDownloading a File If you know the file nameLeaving a Message Reading a MessageIf you don’t know the file name About CompuServe/Internet No Longer Available Multi-Tech Fax-Back Service No Longer AvailableBulletins Appendix a Technical Specifications Command Buffer Intelligent FeaturesData Modulation Fax Modulation22bis/V.22 2400 & 1200 bpsCarrier Frequencies Fax 21 CH2 Half DuplexDiagnostics ConnectorsIndicators Temperature Power RequirementAppendix B Tone Dial Frequencies 697 770 852 941Appendices MT3334ZDX, MT3334ZDXV Appendices Canadian Limitations Notice European Low Voltage Directive Compliance with Babt RequirementsPage Compliance with BS6328 Part Compliance with BS6789 .1 and PartModem Commands Default Permissible Range Modem CE Mark EMC and Safety ComplianceRegister Default Permissible Range Australian and New Zealand Modem Warning NoticeCall Attempts/Retries New Zealand Telecom Warning NoticeIndex Error Correction Page MT5634ZDXv Connections Power Supply Index