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This manual covers installation and operating instructions for the following 3Com modem:
U.S. Robotics 56 kbps Winmodem™
U.S. Robotics is a registered trademark and Connections, RapidComm, and x2 are trademarks of
3Com Corporation and its subsidiaries. Windows is a registered trademark of Microsoft Corp.
CompuServe is a registered trademark of CompuServe Inc. America Online is a registered trademark
of America Online Inc. Any other trademarks, trade names, or service marks used in this manual are
the property of their respective owners.
© 1998 3Com Corporation
7770 North Frontage Road
Skokie, IL 60077-2690
All Rights Reserved
IMPORTANT! In accordance with the ITU-T standard for 56K transmissions, this modem is capable
of 56 Kbps downloads. However, due to FCC rules which restrict power output of the service
providers' modems, current download speeds are limited to 53 Kbps. Actual speeds may vary
depending on line conditions and other factors. Uploads from users to server equipment travel at
speeds up to 31.2 Kbps. An analog phone line compatible with the ITU-T 56K standard or x2
technology, and an Internet provider or corporate host site compatible with the ITU-T 56K standard
or x2 technology are necessary for these high-speed downloads.


   Related Manuals for 3Com 005683-00

   Summary of Contents for 3Com 005683-00

  • Page 1 This manual covers installation and operating instructions for the following 3Com modem: U.S. Robotics 56 kbps Winmodem™ U.S. Robotics is a registered trademark and Connections, RapidComm, and x2 are trademarks of 3Com Corporation and its subsidiaries. Windows is a registered trademark of Microsoft Corp. CompuServe is a registered trademark of CompuServe Inc.
  • Page 2: Table Of Contents

    ABLE OF ONTENTS Welcome to 56k Information Access Product Features Windows 3.x Installation How to Insert the Modem Running the Installation on a Windows 3.1 or 3.11 System Before You Begin (Windows 95 Users) Windows 95 Installation How to Prepare For Plug and Play Checking Your Version of Windows 95 Checking Your System’s Resources How to Insert the Modem...
  • Page 3 ABLE OF ONTENTS Installing Other Fax/Data Software Type of Modem Initialization String Flow Control Using Modem Station Why Modem Station? What Does Modem Station Do? Installing Modem Station Starting Modem Station Using Detect New Modems Using Terminal Using Modem Configurator Using Modem to Computer Using the Extended Information Screens U.S.
  • Page 4 ABLE OF ONTENTS Glossary Regulatory Information Manufacturer’s Declaration of Conformity Caution to the User (Canada) IC UL Listing/CUL Listing Connecting to the Telephone Company Fax Branding Radio and Television Interference For Canadian Modem Users Limited Warranty...
  • Page 5: Welcome To 56k Information Access

    ELCOME TO NFORMATION CCESS The International Telecommunications Union This modem will give you the most (ITU) decides the technical protocols compatibility with high speed downloads from communications devices must use to service providers that offer the ITU 56K interoperate with each other. Modems that standard technology or x2 technology to their comply with ITU standards can “talk to”...
  • Page 6: Product Features

    RODUCT EATURES Modulation Schemes Fax Modulation Schemes Back Channel Link Rates 56K ITU-T standard ITU-T V.17 4800, 7200, 9600, 12000, 14400, x2™ technology ITU-T V.29 16800, 19200, 21600, 24000, ITU-T V.34+ ITU-T V.27ter 26400, 28800, 31200 ITU-T V.34 ITU-T V.21 33600 ITU-T V.32bis Fax Standards...
  • Page 7: Windows 3.x Installation

    INDOWS NSTALLATION These instructions cover the installation of the Winmodem hardware and the accompanying You’ll need these items from your software under Windows 3.x. These U.S. Robotics modem box: instructions are for users of either Windows 3.1, Windows 3.11, or Windows for Workgroups.
  • Page 8: How To Insert The Modem

    INMODEM NSTALLATION UNDER INDOWS This chapter will walk you through the How to Insert the Modem installation of your Winmodem. There are two parts to the installation: hardware (the modem) and software. The modem must be installed NOTE: Before installing your before the software.
  • Page 9 INMODEM NSTALLATION UNDER INDOWS Find an empty ISA expansion slot at least TIP: Before you unplug anything, label as long as the gold edge of your modem. the cords or make a sketch of how (ISA slots have black plastic grooves lined things are connected.
  • Page 10 INMODEM NSTALLATION UNDER INDOWS Holding the modem by each corner, align You’ll have to apply a little pressure to the gold edge with an empty expansion seat the modem properly. Sometimes a slot. Push down gently until the modem gentle back-and-forth motion helps get the snaps into the slot.
  • Page 11 INMODEM NSTALLATION UNDER INDOWS Plug one end of the phone cable that came Plug the power cords, cables, and with the modem into the TELCO jack at peripherals back into the computer and the rear of the modem turn the computer on. If Windows does not start automatically, please start it now.
  • Page 12: Running The Installation On A Windows 3.1 Or 3.11 System

    INMODEM NSTALLATION UNDER INDOWS The next screen will tell you where the Running the Installation Program Winmodem installation files will be located. on a Windows 3.1 or 3.11 For Click Continue to copy the Winmodem Workgroups System files to this directory. If you wish to copy the Winmodem files to a different After inserting the Winmodem follow these directory, type the path to that directory in...
  • Page 13 INMODEM NSTALLATION UNDER INDOWS This screen tells you that the software will This screen tells you that modifications create the new Winmodem directory. have been made to your Windows system Click Yes. files. Click OK. This screen tells you that the software will This screen lets you know the installation automatically detect available software is being loaded to your hard...
  • Page 14 INMODEM NSTALLATION UNDER INDOWS After the software detects the available Your Winmodem software has been COM ports, it will ask you select one for installed. Click Restart Windows to the Winmodem. Highlight the first or finish the process. lowest one and then click OK. Be sure to write the number of the free COM port you select.
  • Page 15 INMODEM NSTALLATION UNDER INDOWS For the I/O address: Choose any on the Windows will now restart. At this point, list. you will see a new Winmodem group. For the IRQ: The COM port/IRQ combinations shown here work with most computer set-ups: (Note: If you do not see a new Winmodem group, you will instead see .....4...
  • Page 16 INMODEM NSTALLATION UNDER INDOWS If you have a sound card, SCSI card, or If you chose an unavailable IRQ, you may game card, it might be using IRQ 5 or 7. Do encounter problems when your not make 5 or 7 your first choice, because it communications software program tells you might not be available.
  • Page 17: Before You Begin (windows 95 Users)

    95 U EFORE EGIN INDOWS SERS Your U.S. Robotics modem is a Plug and Play 4. Double-click Computer and the “Computer device. Windows 95 can automatically identify a Properties” screen appears. Select the option at Plug and Play device and determine if your system the top of the screen to show Interrupt Requests has the resources necessary to support the device.
  • Page 18: Windows 95 Installation

    95 I INDOWS NSTALLATION You’ll need these items from your U.S. Robotics modem box: NOTE: These instructions are for Windows 95 users. Windows 3.x users should go to the “Windows 3.x Installation” section of this manual on page the modem a phone cord How to Prepare for Plug and Play Installation...
  • Page 19 INMODEM INSTALLATION UNDER INDOWS Right-click the My Computer icon in Find your version number in the upper right Windows. corner of the “General” screen shown below. Select Properties. In this example the Windows version is 950a. Make a note of the version you are have. You will follow different instructions later depending on which version you have.
  • Page 20: Checking Your System's Resources

    INMODEM INSTALLATION UNDER INDOWS Check Your System’s Resources 5. Select the Interrupt request (IRQ) option at the top of the screen. Your modem is a Plug and Play device. Windows 95 can automatically identify a Plug and Play device You will see the IRQs your system is currently and determine if your system has the resources using.
  • Page 21: How To Insert The Modem

    INMODEM INSTALLATION UNDER INDOWS How to Insert the Modem TIP: Before you unplug anything, label the cords or make a sketch of how things are connected. This can be helpful when you NOTE: Before installing your modem, plug things back in later. write down its serial number.
  • Page 22 INMODEM INSTALLATION UNDER INDOWS drop the screw into the computer, you will need it later to screw the modem into place. Find an empty ISA expansion slot that’s at least Holding the modem by each corner, align the as long as the gold edge of your modem. (ISA gold edge with an empty expansion slot.
  • Page 23 INMODEM INSTALLATION UNDER INDOWS You’ll have to apply a little pressure to seat the modem properly. Sometimes a gentle back-and- NOTE: The diagram on the below forth motion helps get the modem all the way into shows horizontally aligned expansion slots. the slot.
  • Page 24 INMODEM INSTALLATION UNDER INDOWS If you wish to use a phone through the same phone wall jack as the modem when the WARNING : The phone jack you use modem is not in use, plug your phone’s cord must be an ANALOG phone line (the type into the modem’s PHONE jack.
  • Page 25: Installing The Winmodem Software In Windows 950a

    INMODEM INSTALLATION UNDER INDOWS Installing the Winmodem When you see this screen, insert the Winmodem floppy disk (which came with your Software in Windows 950 or 950a Winmodem) and click OK. This screen will come up when Windows restarts If the Driver from disk… option is not already selected, select it now.
  • Page 26: Installing The Winmodem Software In Windows 950b

    INMODEM INSTALLATION UNDER INDOWS Installing the Winmodem Software in Windows 950b When you see this screen after Windows starts, DO NOT click anything DO NOT press ENTER. Make a note of the COM port and then click OK. You may need this information when installing communications software.
  • Page 27 INMODEM INSTALLATION UNDER INDOWS Then click Next to continue. When you see this screen, click Finish.
  • Page 28 INMODEM INSTALLATION UNDER INDOWS When you see this screen, click OK. NOTE:If you see the screen below instead of the screen preceding, click the Back button. When you see this screen, type A:\. (Be sure to type the period after the backslash) to replace whatever is in the Copy files from box.
  • Page 29 INMODEM INSTALLATION UNDER INDOWS Then click OK.. You will see a series of Double-click the Modem icon. (circled in the screens as files copy and drivers build. screen below.) Finally, you will see a screen telling you that the modem has been installed. Click OK. Check the installation by going into the Control Panel.
  • Page 30: Un-installing The Winmodem Software In Windows

    INMODEM INSTALLATION UNDER INDOWS Un-installing the Winmodem 10. You should then see this screen. Click OK. Software. From the Start menu, point to Settings and then click Control Panel. For instructions on how to install the RapidComm fax/data software, go to the section entitled “Software Installation and Testing”...
  • Page 31 INMODEM INSTALLATION UNDER INDOWS Double click the Modem icon (circled below) Choose the “Port Settings” tab and click the and then click on your Winmodem. Click on the Uninstall button. Properties button.
  • Page 32 INMODEM INSTALLATION UNDER INDOWS To verify that you uninstalled your Winmodem If you uninstalled your Winmodem software due begin at the Start menu and select Control Panel. to a failed installation, please return to the Double-click on the System icon then select the section entitled “Installing the Winmodem Device Manager tab.
  • Page 33: Software Installation And Testing

    OFTWARE NSTALLATION AND ESTING Software Installation and NOTE: The following instructions Registration Using the apply to Windows 3.x and Windows 95 users. However, only Windows 95 Setup Wizard screens are shown. This section tells you how to start the U.S. Robotics Setup Wizard on the ™...
  • Page 34: Starting The Wizard

    OFTWARE NSTALLATION AND ESTING Starting the Wizard 1. From the Windows 95 desktop, click the Start button and then click Run. Click OK. 3. Follow the on-screen instructions to run the Wizard. After running the Wizard, you’ll be given the option to explore other areas of the Connections CD.
  • Page 35: Installing The Rapidcomm Fax/data Software

    OFTWARE NSTALLATION AND ESTING You can also use the CD later. To start the Section. Now double click the RapidComm CD, click the Windows Start menu, point to icon and then double click on the RapidComm Programs, point to U.S. Robotics icon.
  • Page 36: Installing Other Fax/data Software

    NSTALLING THER OFTWARE You can use any other Windows based KEY POINT: Refer to your software fax/data software other than RapidComm. (the manual for the program’s installation fax/data software on the Connections CD). instructions. The software’s installation Your modem was designed for and tested program will ask you questions about the using a wide range of communications software modem you are using.
  • Page 37: Flow Control

    NSTALLING THER OFTWARE Flow Control NOTE: DO NOT select a 28,800, For hardware flow control (highly 14,400, or 12,000 bps serial port rate, if recommended), select RTS/CTS. offered. Your modem will NOT work For software flow control, select correctly with any of these settings. Fix XON/XOFF.
  • Page 38: Using Modem Station

    SING ODEM TATION What Does Modem Station You may want to “tweak” your modem for optimum performance. Modem Station provides a simple to use Installing Modem Station interface that makes communicating with If you did not install Modem Station when you your modem easy.
  • Page 39 SING ODEM TATION 6. You will be asked whether you wish to 9. When you see this screen, click Next to install Modem Station. Click Yes. accept the default directory or click Browse to change directories. 7. Wait a few moments for the Installation Wizard to load.
  • Page 40 SING ODEM TATION 10. Click Next on the following screen to 11. When you see the following screen, click accept the default program folder. You can Finish to complete the installation. place Modem Station in an existing folder by selecting one from the list. If this is the first time you’ve installed Modem Station, you may be asked to restart your computer.
  • Page 41: Starting Modem Station

    1. Click Windows Start button and then point to Programs. Click U.S. Robotics DETECT NEW MODEMS Modem Station (or the folder you This option detects US Robotics modems selected during installation). installed on your system and shows what 2. Click the Modem Station icon. This brings COM port they are using.
  • Page 42 SING ODEM TATION MODEM CONFIGURATOR TIP: For your convenience, we Modem Configurator provides an easy-to-use provide many on-line support interface for entering hard-to-remember avenues. For specific questions, commands. Use Modem Configurator for our fax-on-demand service is a troubleshooting, initial configuration, and tuning good place to start.
  • Page 43: Using Detect New Modems

    SING ODEM TATION 2. Click Scan to have Modem Station check Using Detect New Modems for installed modems. This may take a few 1. Click Detect New Modems to bring up moments. the following screen. 3. When the scan finishes, you will see the following display.
  • Page 44: Using Terminal

    SING ODEM TATION modem and display make and model Modem Configurator without going back to information under the assigned port. All the main menu. Extended Information provides currently active ports should display “Port detailed information about your modem, OK” under the heading. If a port displays a previous connections, firmware dates, etc.
  • Page 45 SING ODEM TATION In addition to allowing direct entry of modem commands, the “Terminal” window also allows NOTE: Modem Station’s you to dial into Bulletin Boards, listing services, Terminal window is provided and other online services. primarily for troubleshooting convenience. If you frequently use BBSs, you will probably want to use a separate, full-featured Terminal program such as that...
  • Page 46 SING ODEM TATION You can end a call by clicking Hang Up at the To the right of the port settings are the port bottom of the screen. speed settings. Port speed is the speed at which your computer sends data to the When you are finished using Terminal, click modem.
  • Page 47: Using Modem Configurator

    SING ODEM TATION Using Modem Configurator Data Control You can access Modem Configurator from This is the “Data Control” screen. either the Main menu or the Detect New Modems screen. Click Modem Configurator to bring up this menu. The “Data Control” screen allows you to assign the following basic communications settings: PORT SPEED...
  • Page 48 SING ODEM TATION For information on using these settings, please refer to the “Glossary” at the back of this manual. TECHNICAL STUFF: switches are tiny switches that Click Help for quick definitions of the control a few basic functions on terminology used in this screen.
  • Page 49 SING ODEM TATION Use the “Connections Control” screen to Click Connection Control to bring up this configure the following settings: screen. DATA TERMINAL READY (DTR) ERROR CORRECTION DATA COMPRESSION CARRIER DETECT For detailed information about these settings, refer to the “Glossary” or the “Technical Quick Reference”...
  • Page 50: Using Modem To Computer

    SING ODEM TATION If you look in the upper left hand corner of the Once you have configured your Connection display, you will see the commands currently in Control settings, click Save to Modem to use. save your settings. The “Modem to Computer” screen allows you to configure the following settings: Using Modem to Computer LOCAL ECHO...
  • Page 51 SING ODEM TATION CONNECTION RATES TIP: If you type ATDT and see The “Connection Rates” screen allows you to ‘AATTDDTT’ on your screen, it is configure modem speeds and protocols. possible that both your software and modem have Local Echo set to ‘ON’. WARNING! Use caution Turn Local Echo ‘OFF’...
  • Page 52 SING ODEM TATION DIALING/ANSWERING This screen allows you to configure the following settings: The next screen allows you to adjust how your modem initiates and receives calls. MODULATIONS V.34 SYMBOL RATES SPEEDS Again, once you have selected your settings, click Save to Modem to save them. When you are finished, click Exit to return to the Modem Configurator menu.
  • Page 53 SING ODEM TATION STORED NUMBERS number when your computer is turned on or when it is reset. This is very useful if you are The “Stored Numbers” screen displays the using your modem with a “dumb terminal” or phone numbers currently stored in your know that you need to connect to a specific modem’s memory.
  • Page 54: Using The Extended Information Screens

    SING ODEM TATION The last option, Restore Defaults, resets your as fully as possible. modem to factory specifications. This option is There are a series of commands used to obtain available from many of the screens within detailed information from U.S. Robotics Modem Station.
  • Page 55 SING ODEM TATION Winmodem users will have access to VxD modem you are using, click Product to bring information via these screens. up the next screen. Courier users will have access to Dial/Security information. Click ROM Checksum to bring up the following screen.
  • Page 56 SING ODEM TATION To see information about the profile in use, The two lines below the connection settings are click Active Profile to bring up the next the advanced commands currently in use. screen. Below them is a display of the contents of the ‘S-Registers’...
  • Page 57 SING ODEM TATION Click Configuration to bring up the first of Options displays the protocols available to these screens. your modem. Fax Options displays your fax compatibility. Clock Frequency displays the speed of the tiny “clock” that controls the timing of operations within the modem.
  • Page 58 SING ODEM TATION Supervisor Date (or EPROM Date) displays the version date of the ‘firmware’ stored in the Supervisor chip. (The Supervisor chip contains the special software used to control your modem’s functions.) If a support representative asks you for your Supervisor or EPROM date, look here.
  • Page 59 SING ODEM TATION Symbol Rate displays the speed of the If you are having connection problems, go transmission. directly to this screen to get this information. If Trellis Code, Nonlinear Encoding, you save anything to the modem between the Shaping, and Precoding all refer to last connection and this screen, the modem will methods of handling high speed data not save these settings.
  • Page 60 U.S. R OBOTICS ODEM PDATE IZARD The Connections CD-ROM, which came with your modem, includes the U.S. Robotics Modem NOTE: Complete the instructions in Update Wizard. This software is designed to the “Software Installation” chapter quickly update your modem to the latest code. (starting on page 29) before installing the...
  • Page 61: Installing The Wizard

    U.S. R OBOTICS ODEM PDATE IZARD 8. When you see the screen below, the setup is Installing the Wizard complete. Click OK. 1. Insert the Connections CD into your CD-ROM drive. 2. Click Start and point to Programs. 3. Point to U.S. Robotics Connections. 4.
  • Page 62: Troubleshooting And Online Help Resources

    ROUBLESHOOTING AND NLINE ESOURCES PROBLEM: PROBLEM: The modem displays double The modem won’t go off hook to dial characters on your monitor. or doesn’t answer the phone. Diagnosis: Diagnosis: The software’s local echo setting is probably You may have plugged your modem’s phone turned on.
  • Page 63 ROUBLESHOOTING AND NLINE ESOURCES Diagnosis: Diagnosis: The phone jack may have been wired You may have plugged your modem’s phone incorrectly. cord into the wrong jack on the modem. Possible Solution: Possible Solution: Contact the telephone company. Ask them to Make sure the phone cord is plugged into a make sure the tip and ring are on the inside jack labeled with the word TELCO or a wall...
  • Page 64 ROUBLESHOOTING AND NLINE ESOURCES Diagnosis: PROBLEM: You may have a poor line connection. Both modems sound like they Possible Solution: exchange carrier signals but fail to Place the call again. Calls are routed differently establish a link. each time. To verify a valid phone connection, enter RapidComm’s Terminal mode, type Diagnosis: ATX3DT18479825092...
  • Page 65 ROUBLESHOOTING AND NLINE ESOURCES Diagnosis: compatible with the 56K ITU standard or The phone line might be wired incorrectly. x2™ technology are necessary for these high- speed downloads. Possible Solution: Contact the telephone company and ask them Possible Solutions: to make sure the tip and ring are on the inside Check http:// for a list...
  • Page 66 ROUBLESHOOTING AND NLINE ESOURCES PROBLEM: NOTE: ATZ4 or AT&F1 are often the Your modem won’t connect at 2400 best reset strings, as they restore bps with a 2400 bps m odem. hardware flow control defaults. Diagnosis: The modem you’re trying to connect with could be an older model that doesn’t support PROBLEM: error control.
  • Page 67 ROUBLESHOOTING AND NLINE ESOURCES Possible Solution: Possible Solution: Set your modem’s word length, parity, and In terminal mode, type AT&F1 and press stop bits the same as the remote modem or ENTER to set hardware flow control. BBS you are calling. PROBLEM: Diagnosis: Your software and modem might not be set to...
  • Page 68 ROUBLESHOOTING AND NLINE ESOURCES Diagnosis: Diagnosis: Optimum flow control settings may not be The remote site you are dialing into may have enabled on your modem. trouble with the file transfer protocol. Possible Solution: Possible Solution: In terminal mode, type AT&F1 and press Try using a different file transfer protocol.
  • Page 69 ROUBLESHOOTING AND NLINE ESOURCES Possible Solution: PROBLEM: Disable any Terminate and Stay Resident Errors are co nstantly occurring in (TSR) programs running in the background. If your V.17 fax transmissions. you have software running as a TSR, check the software’s manual for information about disabling its ability to operate as a TSR.
  • Page 70 ROUBLESHOOTING AND NLINE ESOURCES Diagnosis: PROBLEM: Your baud rate may be set too high. RapidComm fails to initialize the Possible Solution: modem. In your software program, lower the baud rate to 9600, 7200, or 4800. Diagnosis: RapidComm’s port settings may be incorrect. Diagnosis: You may be trying to fax a compressed file.
  • Page 71 ROUBLESHOOTING AND NLINE ESOURCES PROBLEM NOTE to users with an older versions of RapidComm on their Plug and Play does not detect systems: You must uninstall the older your modem. version before installing the most You’ve installed the modem and Windows has recent version (contained on the restarted, but you simply see your desktop.
  • Page 72 ROUBLESHOOTING AND NLINE ESOURCES 2. Click Windows 95 Start, point to Possible Solution: Try the following: Settings, and click Control Panel. Double-click the System icon and then 1. Click Windows 95 Start and click Shut click the Device Manager tab on the Down.
  • Page 73: Online Help Resources

    ROUBLESHOOTING AND NLINE ESOURCES 2. Put the program in Terminal mode. If the computer does not detect the modem 3. Type ATDS0 (the last digit is a zero) and after this second restart, please continue reading this chapter for information about press ENTER.
  • Page 74 ROUBLESHOOTING AND NLINE ESOURCES The introductory screen of the 3Com BBS will 3Com offers a number of other online technical look like the screen shot below. The BBS support options. Choose any one of the gives you access to customer and technical following options for help with and/or more support documents and the BBS library.
  • Page 75: World Wide Web

    ROUBLESHOOTING AND NLINE ESOURCES World Wide Web Customer Support via the Phone A 3Com Web page containing the same information as the Internet on Demand listing. Technical questions about 3Com modems can Log on to: also be answered by technical support specialists.
  • Page 76: Are You Still Having Problems

    ROUBLESHOOTING AND NLINE ESOURCES 1. Insert the Connections CD into your Priority, No-Hold Service CD-ROM drive. 3Com also staffs its own fee-based 900 2. Double-click the My Computer icon on number for immediate assistance. These lines your desktop. are staffed from 8a.m.- 10 p.m. Monday 3.
  • Page 77: If You Need To Return The Modem To 3com

    ROUBLESHOOTING AND NLINE ESOURCES If your dealer can't help you, contact packing material. DO NOT send the modem 3Com Customer Support. When you call, back in the original box. specify your modem serial number (found on the modem and on the outside of the Send ONLY the modem (NOT the power box), the software being used, and, if supply, manuals, CD-ROM, etc.).
  • Page 78: Glossary

    LOSSARY answer mode Cross references are printed in boldface. The mode used by your modem when Cross references with items in the Command answering an incoming call from an originating Summary, found in the Technical Quick modem. The transmit/receive frequencies are Reference, are printed in italics.
  • Page 79 LOSSARY ASCII Auto Answer American Standard Code for Information Sets the modem to pick up the phone line Interchange. A code used to represent letters, when it detects a certain number of rings. See numbers, and special characters such as $, !, S-register S0 in the “Technical Quick and /.
  • Page 80 LOSSARY binary digit buffer A 0 or 1, reflecting the use of the binary A memory area set aside to be used as numbering system (only two digits). Used temporary storage during input and output because the computer recognizes either of two operations.
  • Page 81 LOSSARY character cyclic redundancy checking (CRC) A representation, coded in binary digits, of a An error-detection technique consisting of a letter, number, or other symbol. test performed on each block or frame of data by both sending and receiving modems. The characters per second (CPS) sending modem inserts the results of its tests in A data transfer rate generally estimated from...
  • Page 82 LOSSARY data compression table default A table containing values assigned for each Any settings assumed, at installation, startup or character during a call under MNP5 data reset, by the computer's software and attached compression. Default values in the table are devices.
  • Page 83 LOSSARY digital loopback duplex A test that checks the modem's RS-232 Indicates a communications channel capable of interface and the cable that connects the carrying signals in both directions. See half terminal or computer and the modem. The duplex, full duplex. modem receives data (in the form of digital Electronic Industries Association (EIA) signals) from the computer or terminal, and...
  • Page 84 LOSSARY fax mode full duplex The mode in which the faxmodem is capable of Capable of signal flow in both directions sending and receiving files in a facsimile simultaneously. In microcomputer format. See definitions for V.17, V.27ter, communications, may refer to the suppression V.29.
  • Page 85 LOSSARY ITU-T LAPM An international organization that defines Link Access Procedure for Modems. An standards for telegraphic and telephone error-control protocol defined in ITU-T equipment. For example, the Bell 212A Recommendation V.42. Like the MNP standard for 1200-bps communication in protocols, LAPM uses cyclic redundancy North America is observed internationally as checking (CRC) and retransmission of...
  • Page 86 LOSSARY nonvolatile memory (NVRAM) Microcom Networking Protocol, an error- User-programmable random access memory control protocol developed by Microcom, whose data is retained when power is turned Inc., and now in the public domain. There are off. On the Sportster, it includes four stored several different MNP protocols, but the most phone numbers and the modem settings.
  • Page 87 LOSSARY originate mode protocol The mode used by your modem when initiating A system of rules and procedures governing an outgoing call to a destination modem. The communications between two or more devices. transmit/receive frequencies are the reverse of Protocols vary, but communicating devices the called modem, which is in answer mode.
  • Page 88 LOSSARY remote digital loopback start/stop bits A test that checks the phone link and a remote The signaling bits attached to a character modem's transmitter and receiver. before the character is transmitted during asynchronous transmission. remote echo terminal The sending system displays data sent to the remote system.
  • Page 89 LOSSARY throughput V.21 The amount of actual user data transmitted per An ITU-T standard for modems operating in second without the overhead of protocol asynchronous mode at speeds up to 300 bps, information such as start/stop bits or frame full-duplex, on public switched telephone headers and trailers.
  • Page 90 LOSSARY V.27 V.32 bis An ITU-T standard for facsimile operations An ITU-T standard that extends the V.32 that specifies modulation at 4800 bps, with connection range: 4800, 7200, 9600, 12,000, fallback to 2400 bps. and 14,400 bps. V.32 bis modems fall back to the next lower speed when line quality is V.29 impaired, fall back further as necessary, and...
  • Page 91 LOSSARY V.42 bis XON/XOFF An extension of ITU-T V.42 that defines a Standard ASCII control characters used to specific data compression scheme for use tell an intelligent device to stop/resume during V.42 connections. transmitting data. Ymodem An error-checking protocol that can send A technology that uses the digital telephone several files of data at a time in 1024-byte network to increase the bit rate of the receive...
  • Page 92: Regulatory Information

    EGULATORY NFORMATION Manufacturer’s Declaration received including interference that may cause undesired operations. of Conformity 3Com Corporation Part 68: 7770 North Frontage Road This equipment complies with FCC Rules Part Skokie, Illinois 60077-2690 68. Located on the bottom of the modem is U.S.A.
  • Page 93: Caution To The User

    EGULATORY NFORMATION (Canada) IC This equipment uses the following USOC This digital apparatus does not exceed the jacks: RJ11C. Class B limits for radio noise emissions from digital apparatus set out in the interference- This equipment may not be used on coin causing equipment standard entitled Digital service provided by the telephone company.
  • Page 94: Connecting To The Telephone Company

    EGULATORY NFORMATION Connecting to the Telephone Company Fax Branding It is not necessary to notify the telephone The Telephone Consumer Protection Act of company before installing the modem. 1991 makes it unlawful for any person to use a However, the telephone company may computer or other electronic device, including request the telephone number(s) to which the fax machines, to send any message unless such...
  • Page 95: Radio And Television Interference

    EGULATORY NFORMATION shipped with your modem. If you’re using a interference to radio or television reception, different communications software program, which you can determine by monitoring refer to its manual. reception when the modem is installed and when it is removed from the computer, try to Radio and Television Interference correct the problem with one or more of the This equipment generates and uses radio...
  • Page 96: For Canadian Modem Users

    EGULATORY NFORMATION requirements as prescribed in the appropriate How to Identify and Resolve Radio- Terminal Equipment Technical Requirements TV Interference Problems document(s). The Department does not Stock No. 004-000-0345-4 guarantee the equipment will operate to the U.S. Government Printing Office user’s satisfaction.
  • Page 97 EGULATORY NFORMATION users to connect their equipment to jacks electric inspection authority or electrician, as except in precise situations that are spelled out appropriate. in tariffing arrangements with those companies. NOTICE: The Ringer Equivalence Number (REN) assigned to each terminal device provides an Repairs to certified equipment should be indication of the maximum number of terminals coordinated by a representative designated by...
  • Page 98 EGULATORY NFORMATION AVIS: L'étiquette de Industrie Canada Les réparations de matériel homologué doivent identifie le matériel homologué. Cette étiquette être effectuées par un centre d’entretien certifie que le matériel est conforme à certaines canadien autorisé désigné par le fournissuer. normes de protection, d'exploitation et de La compagnie de télécommunications peut sécurité...
  • Page 99: Limited Warranty

    EGULATORY NFORMATION Avertissment: L’utilisateur ne doit pas tenter Centre de guarantie et de service après-vente: de faire ces raccordements luimême; il doit avoir recours à un service d’inspection des Keating Technologies installations électriques, ou á un électricien, 25 Royal Crest Court, Suite 200 selon le cas.
  • Page 100 EGULATORY NFORMATION not apply if the product is modified, NO EVENT BE LIABLE FOR ANY tampered with, misused, or subjected to SPECIAL, INDIRECT, INCIDENTAL, abnormal working conditions (including, but PUNITIVE, OR CONSEQUENTIAL not limited to, lightning and water damage). DAMAGES OF ANY KIND OR CHARACTER, INCLUDING, THIS LIMITED WARRANTY DOES WITHOUT LIMITATION, LOSS OF...
  • Page 101 EGULATORY NFORMATION warranty, or the exclusion or limitation of modem back in its original box. DO NOT incidental or consequential damages, so the send anything but the modem (do not send above exclusion or limitation may not apply back the power supply, CD-ROM, to you.

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