Multi-Tech Systems MT2834ZPX owner manual Digital Loopback Test/V.54 Loop 2 Local/Manual

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Chapter 6 - Testing Your Modem

5.Your modem passes this test if the data entered from your keyboard are the same as the data received on your monitor. If different data is appearing on your monitor, your modem is probably causing the problem, although it could also be your computer. If your modem passes this test, but you are receiving errors while On-line, the remote modem or the phone line could be at fault.

Note: All Loopback Tests operate at all speeds except 300 bps; and disable error correction (&E0&W0<cr>) before engaging in loopback tests.

Digital Loopback Test/V.54 Loop 2 (Local/Manual)

The Digital Loopback Test is an on-line test that loops data sent from one modem across the phone line to another modem, then back to the first modem. See Figure 6-2.

There are two ways to put a modem into Digital Loopback mode.

1.Locally or Manually, described here in section 6.2.

2.Remotely or Automatically, see section 6.3.

In this test the local modem is placed in Digital Loopback mode. Data is entered and transmitted from the remote modem (which is not in digital loopback mode), sent across the phone line to the local modem and looped back to the remote modem.

The test procedure is as follows:

1.Go into Terminal mode. Type AT and hit ENTER; you should get an OK message.

2.Dial the remote modem by entering the Dial command and the phone number, to establish On-line mode.

3.Type the Escape Sequence (+++AT<CR> or <BREAK>AT<CR>) which brings your modem into Command mode, while still maintaining the pseudo On-line mode with the remote modem.

4.Type ATU3 from the local PC and hit ENTER. Once you receive an OK message from your modem (if responses are enabled), the local modem is placed in Digital Loopback mode.

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Contents Page Record of Revisions Revision Description Contents Index Introduction and Description Modem Features Product Description Fax FeaturesInstallation and Connection How to Use This ManualSoftware Configuration AT Commands and S-RegistersTesting Your Modem Service, Warranty & Technical Support/ BBSAppendices Safety Warnings Installation and ConfigurationConfiguration and Installation Procedure StepProcedure Configuration/Installation ProcedureInstallation and Configuration Is Your MT2834ZPX Ready for Use? Operating Your MT2834ZPX Simple Operations Configuring Software for Your Modem Software Configuration IntroductionAT &F X4 S0= 2 M PC Initialization StringsConfiguring Software for Your Computer Changing Default ParametersTerminal Emulation Configuring Software for the Remote SystemWhen to Disable Data Compression File Transfer ProtocolsAT &F S0=0 X4 &E14 M Disabling Error Correction 16550 Uart and WindowsAT &F S0=0 X4 &E0 M COM2FIFO=1 COMnFIFO=1Page Modem AT Commands Command a Default $BA0 Description Command Values Default $EB0 Description =0 thru $Fn Command Values Default Command Values Default Description Default &P1 Description RFn Command T = 0, 1, 2, or Values Default Description Command @ Remote Configuration Remote Configuration ProceduresRemote Configuration Operation Procedures StepProcedure Contd. Remote Configuration Operation Procedures Password CommandsEscape Code Character RegistersReturn Character Pause Time for Comma S13 Remote Configuration Escape Character S29 Local Inactivity Timer S36 Time Between DTR Inactive and Modem Off-Hook Q0 Multi-Tech Result Codes Result CodesQ1 Standard AT Result Codes AT Commands and S-Register Summary Modem Does Not Respond to Commands TroubleshootingPage Modem Dials But Cannot Make a Connection Page Modem Disconnects While Online Modem Cannot Connect When Answering File Transfer Is Slower Than It Should Be Losing Data Fax and Communications Software Won’t Run at the Same Time Getting Garbage Characters on the MonitorLocal Analog Loopback Test Testing Your Modem Local Analog Loopback Test/V.54 LoopDigital Loopback Test/V.54 Loop 2 Local/Manual Digital Loopback Test local/manual Digital Loopback Test/V.54 Loop 2 Remote/ AutomaticDigital Loopback Test remote/automatic Limited Warranty Service, Warranty and Tech Support IntroductionOn-line Warranty Registration Tech SupportRecording Modem Information Service To log on to the Multi-Tech BBS About the Multi-Tech BBSTo Download a file If you know the file nameIf you don’t know the file name About CompuServe/Internet About the Multi-Tech Fax-Back ServiceAppendix a Technical Specifications Command Buffer Intelligent FeaturesModulation Fax ModulationsCarrier FrequenciesData Carrier Frequencies BpsBell StandardCarrier Frequencies Diagnostics ConnectorsTemperature Power Consumption Dimensions697 770 852 941 1209 Digits 1336 1477 1633 Appendix B Tone Dial FrequenciesAppendix C FCC and Canadian Regulations RJ11C or RJ11W single line Appendix C FCC and Canadian Regulations Canadian Limitations Notice Index 15, 19 In-band Escape Sequence MultiExpress for Windows PBX/CBX Disconnect Drop Time for DSR/CTS/CD Rings Which Have Occurred Registers Serial port 17, 20, 21 17, 19