3Com 005605-00 User manual

This manual covers installation and operating instructions for the following 3Com modems:
U.S. Robotics 56 Kbps∗Voice internal and external modems
3Com, the 3Com logo, and U.S. Robotics are registered trademarks and Connections, RapidComm, and
x2 are trademarks of 3Com Corporation or 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.

TABLE OF CONTENTS
Welcome to 56K Information Access 1
Product Features 2
Before You Begin (Windows 95 Users) 3
Determining Available Resources 3
Determining Your Version of Windows 95 4
Internal Modem Installation with Windows 3.x 5
A Word about COM Ports and IRQs 5
How to Use ComTest to Determine Your Modem’s Settings 7
Testing an Installed Modem 9
What to Do with ComTest’s Recommendation 10
How to Change the Modem’s Settings 12
How to Insert the Modem into the Computer 14
Internal Modem Installation with Windows 95 21
How to Prepare for Plug and Play Installation 22
How to Insert the Modem into the Computer 23
Installing the Modem Drivers 27
External Modem Installation with Windows 95 35
Determining Which Serial Cable to Buy 35
Connecting the Modem to the Computer 37
Installing the Modem Drivers 39

TABLEOFCONTENTS
Software Installation 47
Running the Setup Wizard 47
Using Connections 48
Installing the RapidComm™ Voice Fax/Data/Voice Software 48
Installing Other Fax/Data Software 50
Type of Modem 50
Initialization String 50
Flow Control 51
UART (External Modems Only) 51
Using Modem Station 52
What Does Modem Station Do? 52
Why Modem Station? 52
Installing Modem Station 52
Starting Modem Station 55
Using Detect New Modems 57
Using Terminal 58
Using Modem Configurator 60
Using Modem to Computer 63
Using the Extended Information Screens 67

TABLEOFCONTENTS
U.S. Robotics Modem Update Wizard 74
Installing the Wizard 74
Updating Your Modem 75
Troubleshooting and Online Help Resources 76
RapidComm Voice Troubleshooting Tips 82
If Plug and Play Does Not Detect Your Modem 83
Online Help Resources 84
Are You Still Having Problems? 87
If You Need to Return the Modem to Us for Repair 87
Glossary 88
Regulatory Information 102
Manufacturer’s Declaration of Conformity 102
Limited Warranty 109

WELCOME TO 56K* INFORMATION ACCESS
1
The International Telecommunications Union
(ITU) determines the technical protocols
communications devices must use to
interoperate with each other. Modems that
comply with ITU standards can “talk” to other
standards-compliant modems and fax
machines worldwide.
The ITU has determined a worldwide standard
for 56K modem technology . With a U.S.
Robotics modem, you can get all the Internet
you want from any service provider who offers
the ITU 56K standard or x2™ technology.
This modem allows the greatest compatibility
for high speed downloads from service
providers that offer the ITU 56K standard
technology or x2 technology to their
customers. 3Com is working with providers
everywhere to quickly upgrade their service to
the ITU 56K standard.
*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.

PRODUCT FEATURES
2
Modulation Schemes
56K ITU-T standard
x2™ technology
ITU-T V.34+
ITU-T V.34
ITU-T V.32bis
ITU-T V.32
ITU-T V.22bis
ITU-T V.22
ITU-T V.23
Bell 212A
ITU-T V.21
Bell 103
Error Control and Data
Compression Schemes
ITU-T V.42
ITU-T V.42bis
MNP 2-5
Fax Modulation Schemes
ITU-T V.17
ITU-T V.29
ITU-T V.27ter
ITU-T V.21
Fax Standards
EIA 578 Class 1 FAX
EIA 592 Class 2.0 FAX
Front Channel Link Rates
28000, 29333, 30666, 32000,
33333, 34666, 36000, 37333,
38666, 40000, 41333, 42666,
44000, 45333, 46666, 48000,
49333, 50666, 52000, 53333,
54666, 56000, 57333
Back Channel Link Rates
4800, 7200, 9600, 12000, 14400,
16800, 19200, 21600, 24000,
26400, 28800, 31200
33600
V.34+ Link Rates
4800, 7200, 9600, 12000, 14400,
16800, 19200, 21600, 24000,
26400, 28800, 31200, 33600
V.32bis Link Rates
4800, 7200, 9600, 12000, 14400
Additional Link Rates
300, 1200/75 (V.23), 1200, 2400
Fax Link Rates
2400, 4800, 7200, 9600,
12000, 14400

BEFORE YOU BEGIN (WINDOWS®95 USERS)
3
Determining Available
Resources
Your U.S. Robotics®Voice modem is a Plug
and Play device. Windows®95 can
automatically identify a Plug and Play device
and determine if your system has the resources
necessary to support the device. However,
Plug and Play will not work if you do not have
resources available or if devices on your
system are not reporting resource usage
correctly. Here’s how you can verify that your
system has the necessary resources before
installing the modem:
1. Click the Windows 95 Start button, point
to Settings, and then click Control Panel.
2. Double-click the System icon.
3. When the “System Properties” screen
appears, click the Device Manager tab.
4. Double-click Computer and the
“Computer Properties” screen appears.
5. Select the option at the top of the screen to
show Interrupt Requests (IRQs).
You will see the IRQs your system is currently
using. If IRQs 3, 4, 5, and 7 are being used,
you need to free an IRQ before you begin
installation. This process involves moving a
device from the IRQ you want to use to a
different (and usually higher) IRQ setting.
Please read the documentation for (or contact
the manufacturer of) the device that is currently
using the IRQ you want to use for your modem
to learn more about how to free the IRQ for
your modem.

BEFOREYOUBEGIN(WINDOWS95 USERS)
4
Determining Your Version of
Windows 95
Follow these steps to determine your version
of Windows 95. This information will be
important during installation.
1. Click the My Computer icon on your
desktop with the right mouse button.
2. Click Properties.
3. In the “System Properties” screen, look at
the system information under the General
tab (circled in the following screen image).
The number following the text “Microsoft
Windows 95” will end with “950”, “950a”,
or “950b”. This indicates your version of
Windows 95. Write this number on the
blank below for later reference. Then click
OK.
Windows 95 version _________________

INTERNAL MODEM INSTALLATION WITH WINDOWS®
3.X
5
You will need these items from your
U.S. Robotics®modem box:
modem phone cord
Connections™CD microphone
Plus:
screwdriver (not included)
A Word about COM Ports and
IRQs
Most computer accessories — mouse, sound
card, enhanced graphics card, scanner, etc. —
require a special connection through which
they can communicate with the computer. For
some devices, this connection is called a
communications (or COM) port. Most
computers have 1 or 2 COM ports, though
they can have up to 4. Although internal
modems do not connect to COM ports
directly, they do require a COM port setting,
which is determined by the setting on the
modem’s COM jumper pins.

INTERNALMODEMINSTALLATIONWITHWINDOWS3.X
6
Each COM port uses an interrupt request
(IRQ). An accessory uses an IRQ to get the
attention of your computer’s centralprocessing
unit (CPU) so that the accessory can perform
a task. The computer stops what it’s doing,
depending on the priority of the request, to
help the accessory perform its task. When two
accessories share an IRQ, it’s like two people
asking different questions in unison to a third
person. Just as the person being asked the two
questions cannot understand either request, a
computer can lock up or otherwise fail to
communicate properly with your modem when
there is an IRQ conflict.
KEY POINT: Accessories cannot
share COM ports and should not share
IRQs. When accessories try to share
settings, they will either not work
properly or not work at all.
3Com has set your modem to a default Plug
and Play setting which is ideal for Windows 95
users. In this configuration, the shunts used to
set your modem’s COM port and IRQ settings
are hanging from single jumper pins and will
not affect your modem’s settings. As a
Windows 3.x user, you need to run the
ComTest program (on the ConnectionsCD)
to determine what settings your modem should
use.