If you have Windows NT:

Windows NT users must be in administrator mode to properly add any new hardware.

Turn your computer on. Insert your Installation CD-ROM into your CD-ROM drive before you log in. If the CD-ROM autolaunches and the setup program appears, click Cancel or Close to exit. Click Start, point to Settings, and click Control Panel. Double-click Modems. When the Install New Modem screen appears, click Next to have Windows detect your new modem. When your modem is detected, click Change. Click Have Disk. Make sure the location of your CD-ROM drive is selected. Click OK. Select USRobotics. Select USRobotics 56K Message V.92 (non-PnP). Click OK and then Next. Click Finish. The Modems Properties tab will display the COM port that is assigned to your modem. Click Close. If the System Settings Change window appears, click Yes to restart your computer.

If you have Windows 2000:

Windows 2000 users must be in administrator mode to properly add any new hardware. Your modem will be automatically installed. Follow the update driver procedure below.

Turn your computer on. After you see a message that your new modem has been installed, insert your Installation CD-ROM into your CD-ROM drive. If the CD-ROM autolaunches and the setup program appears, click Cancel or Close to exit. Click Start, select Settings, then click Control Panel. Double-click the System icon. Click the Hardware tab. Click Device Manager. Expand Modems by clicking +. Double-click the description of your new modem or Standard Modem if there is no specific description, then click the Driver tab. Click Update Driver. Click Next. Select Search for a suitable driver for my device. Click Next. Select CD-ROM drive. Click Next. Select Install one of the other drivers, then click Next. Select USRobotics 56K Message V.92. Click Next. A Digital Signature Not Found message will appear. Click Yes. Click Finish to complete the installation.

If you have Windows XP:

Windows XP users must be in administrator mode to properly add any new hardware. Your modem will be automatically installed. Follow the update driver procedure below.

Software Installation for All Windows Operating Systems:

V.92 Features

To install the ControlCenter software, eject and reinsert the Installation CD-ROM into your CD-ROM drive. If the Installation CD-ROM interface does not run automatically, click Start and then click Run. In the Run dialogue box, type D:\setup.exe. If your CD-ROM drive uses a different letter, type that letter in place of D. Choose the Software option, and follow the on-screen instructions to install the ControlCenter software.

The PhoneTools software allows you to use all the voice functionality of your new V.92 modem.

To install the PhoneTools software, eject and reinsert the Installation CD-ROM into your CD-ROM drive. If the Installation CD-ROM interface does not run automatically, click Start and then click Run. In the Run dialogue box, type D:\setup.exe. If your CD-ROM drive uses a different letter, type that letter in place of D. Choose the Software option, select PhoneTools, and then follow the on-screen instructions to install PhoneTools software.

Register your modem.

At the Installation CD-ROM interface, click the Support link. Follow the on-screen instructions to register your modem and to view the warranty information. If the Installation CD-ROM interface does not run automatically, click Start and then click Run. In the Run dialogue box, type D:\setup.exe. If your CD-ROM drive uses a different letter, type that letter in place of D. You can also register online at: http://www.usr.com/productreg.

Troubleshooting

If you have any difficulty with your modem, first make sure that it was installed correctly.

Windows Me, 98, 95

Click Start, Settings, and then Control Panel.
Double-click the Modems icon. In the Modems Properties screen, you should see a description for your new USRobotics modem. If you do not see a description of your modem, see the Note at the end of this section. Click the Diagnostics tab. Make sure that the correct COM port (modem) is selected. Click the More Info button. You should see a series of commands and responses from the modem. This means that the installation was a success. If you do not see commands and responses, shut down and restart your computer. To determine if your modem is functioning properly, repeat the steps above. If your modem is still not working, refer to the additional troubleshooting in this Guide.

Windows NT

Windows NT users must be in administrator mode to properly add any new hardware.

Click Start, Settings, and then Control Panel.
Double-click the Modems icon. In the Modems Properties screen, you should see a description for your new USRobotics modem. If you do not see your modem listed, shut down and restart your computer. To determine if your modem is functioning properly, try reinstalling your modem. If your modem is still not working, refer to the additional troubleshooting in this Guide.

Windows 2000

Windows 2000 users must be in administrator mode to properly add any new hardware.

Click Start, Settings, and then Control Panel. Double-click the Phone and Modem Options icon. Click the Modems tab. Make sure that your new USRobotics modem is selected. If you do not see a description of your modem, see the Note at the end of this section. Click the Properties button. Click the Diagnostics tab. Click the Query Modem button. You should see a series of commands and responses from the modem. This means that the installation was a success. If you do not see commands and responses, shut down and restart your computer. To determine if your modem is functioning properly, repeat the steps above. If your modem is still not working, refer to the additional troubleshooting in this Guide.

Windows XP

Windows XP users must be in administrator mode to properly add any new hardware.

Click Start and then click Control Panel.
Click Phone and Modem Options and then click the Modems tab. You should see a description of your new USRobotics modem and a COM port setting. If you do not see a description of your modem, see the Note at the end of this section. Click Modem, highlight the description of your new modem, and click Properties. Click the Diagnostics tab. Click the Query Modem button. You should see a series of commands and responses from the modem. This means that the installation was a success. If you do not see commands and responses, shut down and restart your computer. To determine if your modem is functioning properly, repeat the steps above. If your modem is still not working, refer to the additional troubleshooting in this Guide.

Note: If your modem is not listed and/or you do not see a series of commands and responses, make sure that your cables are attached correctly to your computer. If your modem still does not work, refer to the additional troubleshooting in this Guide. Shut down and restart your computer. To verify that your modem is functioning properly, repeat the steps listed under your specific operating system.

For additional troubleshooting help, review these common issues:

PROBLEM: My computer isn’t recognizing my modem.

Possible solution:

You may be using a COM port that is either already in use or not configured correctly. For the modem to work properly, it must be plugged into an enabled serial port which is assigned to a free COM port. Most computers have two serial ports assigned to COM 1 and COM 2 respectively.

Windows XP, 2000

Make sure your COM port is not already in use by another modem. Click Start, Settings (for Windows 2000 only), and Control Panel, and then double-click Phone and Modem Options. Click the Modems tab. Look for a listed modem and check which COM port it is using. If a previous modem is already using the available COM port, you can either use another COM port or uninstall the modem that was installed previously. See your previous modem’s manual for uninstallation instructions. Next, make sure that your COM ports are configured correctly. Right-click the My Computer icon on your desktop. Click Properties. Click the Hardware tab. In the Device Manager section, click the Device Manager button. Look under Ports (COM and LPT). If the Communications ports have yellow exclamation points or red Xs over them, your COM ports may be configured incorrectly. If this is the case, you may need to contact your computer manufacturer. It is also possible that you may be plugging your external modem’s cable into a disabled serial port. Refer to your computer’s manual for information about enabling COM ports. This usually involves altering the BIOS settings and possibly the operating system. You may need to call your computer’s manufacturer to change your BIOS settings if they are incorrect.

Windows Me, 98, 95

Make sure your COM port is not already in use by another modem. Click Start, Settings, and Control Panel, and then double-click Modems. If you have Windows Me and you do not see this icon, be sure to select View All Control Panel Options. Look for another modem listed and if another modem is listed, click the Diagnostics tab to find out which COM port it is using. If a previous modem is already using the available COM port, you can either use another COM port or uninstall the previously installed modem. See your previous modem’s manual for uninstallation instructions. Next, make sure that your COM ports are configured correctly. Right-click the My Computer icon on your desktop. Click Properties. Click the Device Manager tab. Look under Ports (COM and LPT). If the COM ports have yellow exclamation points or red Xs over them, your COM ports may be configured incorrectly. If this is the case and you are not sure how to properly configure your COM ports, contact your computer manufacturer.

It is also possible that you may be plugging your RS-232 modem cable into a disabled serial port. Refer to your computer’s manual for information about enabling COM ports. This usually involves altering the BIOS settings and possibly the operating system. You may need to call your computer’s manufacturer to change your BIOS settings if they are incorrect.

Windows NT

Click Start, Settings, and then Control Panel. Double-click Ports. Make sure the port you are plugging the modem into appears in the list. If it does not, the port needs to be added, and possibly enabled in the BIOS. Consult your Windows NT manual for information about adding ports. After you add or enable the port, follow the instructions in this Guide for your operating system.

PROBLEM: My software isn’t recognizing my modem.

Possible solution:

Your communications software may not function properly if you have more than one version of the software installed or if you are using an older version. We highly recommend using the communications software provided with your modem on the Installation CD-ROM.

Possible solution:

Make sure the modem is plugged in and turned on. If it is, check the outlet with another electric device (like a lamp) to be sure that you are getting power. Also, you must use the power supply that came with your modem; other similar-looking power supplies may be of different voltages and could damage your modem. When your modem is properly connected to an electrical outlet, a wall outlet, or a surge protector and is turned on, the CS light on the front panel will be illuminated.

Possible solution:

Windows XP, 2000

You may not have the correct modem type selected in your software or in Windows. Click Start, Settings (Windows 2000 only), and then Control Panel. When Control Panel opens, click Phone and Modem Options. Click the Modems tab. Here you will see a list of installed modems. You can also add, remove, or view the properties of modems from this window. The USRobotics modem you have installed should be present in the list of installed modems. If none of the modem descriptions in the list matches your USRobotics modem or no modems are listed, your modem is not properly installed. Try reinstalling your modem using the instructions on this Guide for your operating system.

Windows Me, 98, 95, NT

You may not have the correct modem type selected in your software or in Windows. Click Start, Settings, and Control Panel. When Control Panel opens, double-click Modems. Here you will see a list of installed modems. You can also add, remove, or view the properties of modems from this window. The USRobotics modem you have installed should be present in the list of installed modems. If none of the modem descriptions in the list matches your USRobotics modem or no modems are listed, your modem is not properly installed. Try reinstalling your modem using the instructions in this Guide for your operating system.

Possible solution:

Windows XP

If you are using Dial-Up Networking, it may not be configured correctly. Check your configuration and make sure you have the correct port selected. Click Start, Control Panel, and double-click Network Connections. Double-click the description of the dial-up networking connection, and select Properties. Make sure that the description in the Connect Using box (under the General tab) matches the description of the modem you are using. If it doesn’t match, select the proper modem description.

Windows 2000

If you are using Dial-Up Networking, it may not be configured correctly. Check your configuration and make sure you have the correct port selected. Click Start, point to Settings, and click Network and Dial-up Connections. Make sure that the description in the Connect Using box (under the General tab) matches the description of the modem you are using. If it doesn’t match, select the proper modem description.

Windows Me, 98, 95, NT

If you are using Dial-Up Networking, it may not be installed or configured correctly. Check your configuration and make sure you have the correct port selected. Double-click My Computer. If you are using Windows Me, click Start, point to Settings, then double-click Control Panel. All operating systems should then double-click Dial-Up Networking, right-click the connection you are trying to use, and select Properties. Make sure that the description in the modem box matches the description of the modem you are using. If it doesn’t match, select the proper modem description.

PROBLEM: My modem won’t dial out or doesn’t answer incoming calls.

For both dialing and answering problems:

Possible solution:

Make sure that you are using the power supply that came with your modem; other similar-looking power supplies may be of different voltages and could damage your modem.

Possible solution:

You might have a bad phone cord connected to your modem, or your phone cord may be plugged into the wrong jack. The phone cord should be plugged into the jack labelled on the modem and directly into the telephone wall jack. Use the phone cord included in your modem’s box, if possible.

Possible solution:

You may have devices between the modem and the phone jack. There should be no line splitters, fax machines, or other devices between the modem and the telephone wall jack.

Office Users

Possible solution:

You may have plugged your modem’s phone cord into a digital line, which can damage your modem. Contact your phone system administrator if you are unsure whether or not your phone line is digital. If your phone system requires dialing “9” to access an outside line, be sure to add “9” before the number you are dialing.

Dialing Problems for Voice Mail Users

Possible solution:

If you have voice mail provided by your local phone company, your dial tone may be altered when messages are waiting. Retrieve your voice mail to restore your normal dial tone.

PROBLEM: My modem sounds like it’s trying to connect to another modem but fails.

Possible solution:

You may have a poor connection. All calls are routed differently, so try placing the call again.

PROBLEM: My modem isn’t achieving a 56K Internet connection.

Our research has shown that the vast majority of telephone lines can and do support V.90/V.92 connections. The V.90/V.92 protocol allows for connection speeds of up to 56K, but line conditions may affect the actual speeds during a given connection. Due to unusual telephone line configurations, some users will not be able to take full advantage of V.90/V.92 technology at this time. In order to achieve a V.90/V.92 connection:

• The server you are dialing into must support and provide a digital V.90/V.92 signal. Your ISP (Internet Service Provider) can provide you with a list of dial-up connections and information on what those connections currently support.
• The telephone line between your ISP and your modem must be capable of supporting a 56K connection and contain only one analogue-to-digital conversion. The 56K signal from your ISP begins as a digital signal. Somewhere between the ISP and your modem, there will be a digital-to-analogue signal conversion so that your modem can receive the data. There must be no more than one analogue-to-digital signal conversion in the path from your ISP to your modem. If more than one analogue-to-digital conversion occurs, your connection speeds will default to V.34+ (33.6 Kbps). There may also be impairments on the local lines between your ISP and your modem. These impairments can prevent or limit connection speeds. All telephone calls are routed differently, so you should try making your 56K connection several times. One way to test this is to dial into a long distance location. Long distance lines are often much clearer than local lines. It is important to note that telephone companies are constantly upgrading their systems. Lines that do not support 56K today may support 56K in the near future.
• For a V.90 connection, your modem must be connecting to a V.90/56K server. A pair of 56K modems will not connect to each other at V.90/56K speeds.
• For a V.92 connection, your modem must be connecting to a V.92 server. A pair of 56K modems will not connect to each other at V.92/56K speeds.

Technical Reference

Front Panel Lights

Typing Commands

• In terminal mode, type commands in either upper or lower case, not a combination. Use the Backspace key to delete errors. (You cannot delete the original AT command because it is stored in the modem buffer.)
• If a command has numeric options and you do not include a number, zero is assumed. For example, if you type ATB, the command ATB0 is assumed.
• Every command except A/, +++, and A> must begin with the AT prefix and be entered by pressing ENTER.
• The maximum command length is 58 characters. This does not include the AT prefix, carriage returns, or spaces.
  

All defaults are based on the &F1*Hardware Flow Control template loaded in NVRAM when the modem is shipped.

Basic Data Commands

<control key>S

Stop or restart help screens.

<control key>C or <control key>K

Stop help screens.

$ Use in conjunction with D, S, or & commands (or just AT) to display a basic command list; online help.

A Manual Answer goes off hook in answer mode. Pressing any key aborts the operations.

A/ Re-executes the last issued command. Used mainly to redial. This does not require the AT prefix or a Carriage Return.

A> Re-executes the last issued command continuously, until the user intervenes or the command is executed forever. Does not require the AT prefix or a Carriage Return.

Any key Aborts off-hook dial/answer operation and hangs up.

AT Required command prefix, except with A/, +++, and A>. Use alone to test for OK result code.

XN Sets result code displayed, default is X4

*Requires @ in dial string; replaces NO CARRIER

Extended Data Commands

&$ Displays a list of ampersand (&) commands

&An Enables/disables additional result code subsets, see Xn

&A0 ARQ result codes disabled
&A1 ARQ result codes enabled
&A2 Modulation indicator added
&A3 Protocol indicators added*LAPM/MNP/NONE (error control) and V.42 bis/MNP5 (data compression)

&Bn Manages modem's serial port rate

&B0 Variable, follows connection rate
&B1 Fixed serial port rate
&B2 Fixed in ARQ mode, variable in non-ARQ mode

&Cn Controls Carrier Detect (CD) signal

&C0 CD override
&C1 Normal CD operations

&Dn Controls Data Terminal Ready (DTR) operations

&D0 DTR override
&D1 DTR toggle causes online Command mode
&D2 Normal DTR operations
&D3 Resets on receipt of DTR

&Fn Loads a read-only (non-programmable) factory configuration

&F0 Generic template; no flow control
&F1 Hardware flow control template
&F2 Software flow control template

&Gn Sets Guard Tone

&G0 No guard tone, U.S. and Canada
&G1 550 Hz guard tone, some European countries, requires B0 setting
&G2 1800 Hz guard tone, U.K., requires B0 setting

&Hn Sets Transmit Data (TD) flow control, see also &Rn

&H0 Flow control disabled
&H1 Hardware flow control, Clear to Send (CTS)
&H2 Software flow control, Xon/Xoff
&H3 Hardware and software flow control

&In Sets Receive Data (RD) software flow control, see also &Rn

&I0 Software flow control disabled
&I1 Xon/Xoff signals to your modem and remote system
&I2 Xon/Xoff signals to your modem only

&Kn Enables/disables data compression

&K0 Data compression disabled
&K1 Auto enable/disable
&K2 Data compression enabled
&K3 MNP5 compression disabled

&Mn Sets Error Control (ARQ) for connections at 1200 bps and higher

&M0 Normal mode, error control disabled
&M1 Reserved
&M2 Reserved
&M3 Reserved
&M4 Normal/ARQ
&M5 ARQ mode

&Nn Sets connect speed, if connection cannot be made at this speed, the modem will hang up. When used in conjunction with &Un and &Un is greater than 0, &Nn sets the ceiling connect speed. &Un sets the floor connect speed. (See also the table in the &Un section.)

Note: &N17 through &N39 apply only to V.90 products.

&N0 Connection speed is determined by the remote modem

&N1 300 bps
&N2 1200 bps
&N3 2400 bps
&N4 4800 bps
&N5 7200 bps
&N6 9600 bps
&N7 12,000 bps
&N8 14,400 bps
&N9 16,800 bps
&N10 19,200 bps
&N11 21,600 bps
&N12 24,000 bps
&N13 26,400 bps
&N14 28,800 bps
&N15 31,200 bps
&N16 33,600 bps
&N17 28,000 bps
&N18 29,333 bps
&N19 30,666 bps
&N20 32,000 bps
&N21 33,333 bps
&N22 34,666 bps
&N23 36,000 bps
&N24 37,333 bps
&N25 38,666 bps
&N26 40,000 bps
&N27 41,333 bps
&N28 42,666 bps
&N29 44,000 bps
&N30 45,333 bps
&N31 46,666 bps
&N32 48,000 bps
&N33 49,333 bps
&N34 50,666 bps
&N35 52,000 bps
&N36 53,333 bps
&N37 54,666 bps
&N38 56,000 bps

&Pn Sets pulse (rotary) dial make /break ratio

&P0 Pulse Dialling Disabled (Default for CTR/TBR-21)
&P1 Denmark, Germany, Austria, Finland, Switzerland, Netherlands, Italy, U.S., South Africa, Czech Republic
&P2 France, U.K., Belgium, Ireland, Spain, Portugal, Australia, Asia, Korea
&P3 Norway
&P4 New Zealand
&P5 Japan
&P6 Sweden
&P7 Not Utilised

&Rn Sets Receive Data (RD) hardware low control, Request to Send (RTS), see also &Hn

&R0 Reserved
&R1 Modem ignores RTS
&R2 Received Data to computer only on RTS

&Sn Controls Data Set Ready (DSR) operations

&S0 DSR override; always ON
&S1 Modem controls DSR

&Tn Begins test modes

&T0 Ends testing
&T1 Analogue Loopback
&T2 Reserved
&T3 Local Digital Loopback
&T4 Enables Remote Digital Loopback
&T5 Prohibits Remote Digital Loopback
&T6 Initiates Remote Digital Loopback
&T7 Remote Digital with self-test and error detector
&T8 Analogue Loopback with self-test and error detector

&Un When set above 0, the value chosen from the table sets the floor connect speed (the lowest acceptable connect speed). If a connection cannot be made at or above this speed, the modem will hang up. This command can also be used in conjunction with &Nn.

Note: &U17 through &U39 apply only to V.90 products.

&Un (continued) When set above 0, the value chosen from the table sets the floor connect speed (the lowest acceptable connect speed). If a connection cannot be made at or above this speed, the modem will hang up. This command can also be used in conjunction with &Nn.

&U0 No restrictions on the minimum speed for the connection

&U1 300 bps
&U2 1200 bps
&U3 2400 bps
&U4 4800 bps
&U5 7200 bps
&U6 9600 bps
&U7 12,000 bps
&U8 14,400 bps
&U9 16,800 bps
&U10 19,200 bps
&U11 21,600 bps
&U12 24,000 bps
&U13 26,400 bps
&U14 28,800 bps
&U15 31,200 bps
&U16 33,600 bps
&U17 28,000 bps
&U18 29,333 bps
&U19 30,666 bps
&U20 32,000 bps
&U21 33,333 bps
&U22 34,666 bps
&U23 36,000 bps
&U24 37,333 bps
&U25 38,666 bps
&U26 40,000 bps
&U27 41,333 bps
&U28 42,666 bps
&U29 44,000 bps
&U30 45,333 bps
&U31 46,666 bps
&U32 48,000 bps
&U33 49,333 bps
&U34 50,666 bps
&U35 52,000 bps
&U36 53,333 bps
&U37 54,666 bps
&U38 56,000 bps

&Wn Writes current configuration to NVRAM templates

&W0 Modifies the NVRAM 0 template (Y0)
&W1 Modifies the NVRAM 1 template (Y1)

&Yn Sets break handling

&Y0 Destructive, but does not send break
&Y1 Destructive, expedited
&Y2 Nondestructive, expedited
&Y3 Nondestructive, unexpedited

&Zn=s Writes phone number string s at position n (n = 0*3)

&Zn=L Writes last executed dial string at position n (n = 0*3)

&Zn? Displays the phone number stored at position n (n = 0*3)

&ZL? Displays the last executed dial string

Caller ID Feature
The Caller ID feature discloses the identification of the caller prior to answering the call. You can enable/disable this feature through the software application and are then able to view the calling telephone number from within a dialing window. Messages retrieved from Independent mode will be stored with identification within the software mailbox.

#CID=n Controls Caller ID feature

#CID=0 Caller ID disabled
#CID=1 Caller ID enabled with formatted information
#CID=2 Caller ID enabled with unformatted information

+++ Escapes to online-command mode

S-Registers

To change a setting, use the ATSr=n command, where r is the register and n is a decimal value from 0 * 255 (unless otherwise indicated).

Fax Commands

Screen Messages

The Serial Interface

The serial interface is a standard developed by the Electronic Industries Association (EIA). It defines the signals and voltages used when data is exchanged between a computer and a modem or serial printer.

The entire standard covers many more functions than are used in most data communications applications. Data is transmitted between the devices over a shielded serial cable with a 25-pin male (DB-25) connector to the modem and a 25-pin, 9-pin, 8-pin, or custom-built connector to the computer.

The use of a shielded cable when connecting a modem to a computer is recommended to ensure minimal interference with radio and television.

Pin assignments are factory-set in the USRobotics modem to match the standard DB-25 assignments in the following table. DB-9 connectors for IBM/AT-compatible computers should be wired at the computer end of the cable as shown in the DB-9 column.

Serial Interface Pin Definitions

Signal Source

Glossary

asynchronous transmission
Data transmission in which the length of time between transmitted characters may vary. Since the time lapses between transmitted characters are not uniform, the receiving modem must be signalled as to when the data bits of a character begin and then they end. The addition of start/stop bits to each character serves this purpose.

auto answer
In this setting the modem can pick up the phone line when it detects a certain number of rings. See S-register S0 in the "Technical Reference" section.

autodial
A process where your modem dials a call for you. The dialling process is initiated by sending an ATDT (dial tone) or ATDP (dial pulse) command followed by the telephone number to dial. Autodial is used to dial voice numbers. See command Dn.

baud rate
A term used to measure the speed of an analogue transmission from one point to another. Although not technically accurate, baud rate is commonly used to mean bit rate.

binary digit
A 0 or 1, which reflects the use of the binary numbering system. It is used because the computer recognises either of two states, OFF or ON. The shortened form of binary digit is bit.

bit rate
This refers to the number of binary digits, or bits, transmitted per second (bps). It is also referred to as transmission rate. Communications channels using telephone channel modems are established at set bit rates, commonly 2400, 4800, 9600, 14,400, 28,800 and higher.

bits per second (bps)
This is the bits (binary digits) per second rate. Thousands of bits per second are expressed as kilobits per second or kbps.

buffer
A memory area set aside to be used as temporary storage during input and output operations. An example is the modem's command buffer.

byte
A group of binary digits stored and operated upon as a unit. In user documentation, the term usually refers to 8-bit units or characters. One kilobyte (KB) is equal to 1,024 bytes or characters; 640 KB indicates 655,360 bytes or characters.

carrier
A tone signifying a connection the modem can alter to communicate data across telephone lines.

character
A representation, coded in binary digits, of a letter, number, or other symbol.

characters per second (CPS)
A data transfer rate generally estimated from the bit rate and the character length. For example, at 2400 bps, 8-bit characters with start/stop bits (for a total of ten bits per character) will be transmitted at a rate of approximately 240 characters per second (cps). Some protocols, such as error-control protocols, employ advanced techniques such as longer transmission frames and data compression to increase cps.

class 1 and 2.0
International standards used between fax application programs and faxmodems for sending and receiving faxes.

cyclic redundancy checking (CRC)
An error-detection technique consisting of a test performed on each block, or frame, of data by both sending and receiving modems. The sending modem inserts the results of its tests in each data block in the form of a CRC code. The receiving modem compares its results with the received

CRC
code and responds with either a positive or negative acknowledgement.

data communications
A type of communications in which computers are able to exchange data over an electronic medium.

data compression table
A table containing values assigned for each character during a call under MNP5 data compression. Default values in the table are continually altered and built during each call: The longer the table, the more efficient throughput gained.

data mode
The mode in which the faxmodem is capable of sending and receiving data files. A standard modem without fax capabilities is always in data mode.

DCE
Data Communications Equipment (or Circuit-Terminating Equipment) is equipment such as dial-up modems that establish and control the data link via the telephone network.

default
Any setting assumed, at startup or reset, by the computer's software and attached devices. The computer or software will use these settings until changed by the user or other software.

detect phase
In the ITU-T V.42 error-control protocol, the first stage in establishing if both modems attempting to connect have V.42 capability.

dictionary
The term used for compression codes built by the V.42 bis data compression algorithm.

digital loopback
A test that checks the modem's RS-232 interface and the cable that connects the terminal (computer) and the modem. The modem receives data (in the form of digital signals) from the computer or terminal, and immediately returns the data to the screen for verification.

digital signals
Signals that are discrete and uniform. In this manual, the term refers to the binary digits 0 and 1. These signals are in contrast with analogue signals.

DTE
Data Terminal (or Terminating) Equipment is a computer that generates or is the final destination of data.

duplex
Duplex indicates a communications channel capable of carrying signals in both directions. See half duplex, full duplex.

Electronic Industries Association (EIA)
This association is a group which defines electronic standards in the U.S.

error control
A variety of techniques that check the reliability of characters (parity) or blocks of data. V.42 and MNP error-control protocols use error detection (CRC) and retransmission of flawed frames (ARQ).

facsimile
A method for transmitting the image on a page from one point to another. This is commonly referred to as fax.

fax mode
The mode in which the faxmodem is capable of sending and receiving files in a facsimile format. See definitions for V.17, V.27ter, V.29.

flow control
A mechanism that compensates for differences in the flow of data into and out of a modem or other device. See commands &Hn, &In, &Rn.

frame
A data communications term for a block of data with header and trailer information attached. The added information usually includes a frame number, block size data, error-check codes, and Start/End indicators.

full duplex
These signals will flow in both directions at the same time over one line. In microcomputer communications, may refer to the suppression of the online local echo.

half duplex
These signals will flow in both directions, but only one way at a time. In microcomputer communications, may refer to activation of the online local echo, which causes the modem to send a copy of the transmitted data to the screen of the sending computer.

Hz
Hertz is a frequency measurement unit used internationally to indicate cycles per second.

ITU-T
An international organisation that defines standards for telegraphic and telephone equipment. For example, the Bell 212A standard for 1200 bps communication in North America is observed internationally as ITU-T V.22. For 2400 bps communication, most U.S. manufacturers observe V.22 bis.

LAPM
Link Access Procedure for Modems is an error-control protocol defined in ITU-T Recommendation V.42. Like the MNP protocols, LAPM uses cyclic redundancy checking (CRC) and retransmission of corrupted data (ARQ) to ensure data reliability.

local echo
A modem feature that enables the modem to display keyboard commands and transmitted data on the screen. See command En.

MNP
Microcom Networking Protocol is an error-control protocol developed by Microcom, Inc., and now in the public domain. There are several different MNP protocols, but the most commonly used one ensures error-free transmission through error detection (CRC) and retransmission of erred frames.

modem
A device that transmits/receives computer data through a communications channel such as radio or telephone lines. It also changes signals received from the phone line back to digital signals before passing them to the receiving computer.

nonvolatile memory (NVRAM)
A user-programmable random access memory which retains data when power is turned off. On some modems, it includes four stored phone numbers and the modem settings.

off/on hook
Modem operations that are the equivalent of manually lifting a phone receiver (taking it off-hook) and replacing it (going on-hook).

online fall back/fall forward
A feature that allows a high-speed, error-control modem to monitor line quality and fall back to the next lower speed in a defined range if line quality diminishes. As line conditions improve, the modem switches up to the next higher speed.

originate mode
The mode used by your modem when initiating an outgoing call to a destination modem. The transmit/ receive frequencies are the reverse of the called modem, which is in answer mode.

parity
A simple error-detection method that checks the validity of a transmitted character. Character checking has been surpassed by more reliable and efficient forms of error checking, including V.42 and MNP 2-4 protocols. Either the same type of parity must be used by two communicating computers, or both may omit parity.

protocol
A system of rules and procedures governing communications between two or more devices. Protocols vary, but communicating devices must follow the same protocol in order to exchange data. The format of the data, readiness to receive or send, error detection and error correction are some of the operations that may be defined in protocols.

RAM
Random Access Memory is memory that is available for use when the modem is turned on, but that clears of all information when the power is turned off. The modem's RAM holds the current operational settings, a flow control buffer, and a command buffer.

remote digital loopback
A test that checks the phone link and a remote modem's transmitter and receiver.

remote echo
A copy of the data received by the remote system, returned to the sending system, and displayed on the screen. Remote echoing is a function of the remote system.

ROM
Read Only Memory is permanent memory, which is not user-programmable.

serial transmission
The consecutive flow of data in a single channel. Compare it to parallel transmissions where data flows simultaneously in multiple channels.

start/stop bits
These signalling bits are attached to a character before and after the character is transmitted during asynchronous transmission.

terminal
A device whose keyboard and display are used for sending and receiving data over a communications link. This device differs from a microcomputer or a
mainframe in that it has little or no internal processing capabilities.

terminal mode
Software mode that allows direct communication with the modem. This mode is also known as command mode.

throughput
The amount of actual user data transmitted per second without the overhead of protocol information such as start/stop bits or frame headers and trailers. Compare it with characters per second.

V.8
The ITU-T standard specification that covers the initial handshaking process.

V.17
An ITU-T standard for making facsimile connections at 14,400 bps, 12,000 bps, 9600 bps, and 7200 bps.

V.21
An ITU-T standard for modems operating in asynchronous mode at speeds up to 300 bps, full-duplex, on public-switched telephone networks.

V.22
An ITU-T standard for modem communications at 1200 bps, compatible with the Bell 212A standard observed in the U.S. and Canada.

V.22 bis
An ITU-T standard for modem communications at 2400 bps. The standard includes an automatic link negotiation fallback to 1200 bps and compatibility with Bell 212A/V.22 modems.

V.23
An ITU-T standard for modem communication at 1200 bps with a 75 bps back channel.

V.27ter
An ITU-T standard for facsimile operations that specifies modulation at 4800 bps, with fallback to 2400 bps.

V.29
An ITU-T standard for facsimile operations that specifies modulation at 9600 bps, with fallback to 7200 bps.

V.32
An ITU-T standard for modem communications at 9600 bps and 4800 bps. V.32 modems fall back to 4800 bps when line quality is impaired.

V.32 bis
An ITU-T standard that extends the V.32 connection range: 4800, 7200, 9600, 12,000, and 14,400 bps. V.32 bis modems fall back to the next lower speed when line quality is impaired, fall back further as necessary, and also fall forward (switch back up) when line conditions improve.
See online fall back/fall forward.

V.34
An ITU-T standard that currently allows data rates as high as 28,800 bps and 33,600bps.

V.42
An ITU-T standard for modem communications that defines a two-stage process of detection and negotiation for LAPM error control.

V.42 bis
An extension of ITU-T V.42 that defines a specific data compression scheme for use during V.42 connections.

V.90/V.92
The ITU-T standard for 56 Kbps modem communications.

Xmodem
The first of a family of error control software protocols used to transfer files between modems. These protocols are in the public domain and are available from many bulletin board services.

Xon/Xoff
Standard ASCII control characters used to tell an intelligent device to stop/resume transmitting data.

Ymodem
An error-checking protocol that can send several files of data at a time in 1024-byte (1K) blocks. This protocol can use either checksums or CRC for error checking.

Ymodem G
This is similar to the Ymodem, except it relies on the modem for error checking, which makes it faster.

Zmodem
This is similar to Xmodem and Ymodem, except it includes batch transfer, the ability to recover from a partially complete transfer, an autostart feature, and improved efficiency.

Regulatory Information

CE Compliance

We, USRobotics Corporation of 935 National Parkway, Schaumburg, Illinois, 60173-5157 USA, declare under our sole responsibility that the product, 56K Message Modem, Model 5668, to which this declaration relates, is in conformity with the following standards and/or other normative documents.

EN60950: 1992, Incl. Amdt. 1-4
EN55022: 1998
EN55024: 1998
EN61000-3-2: 1996/A12
EN61000-3-3: 1995

We hereby declare that the above named product is in conformity with the essential requirements and other relevant provisions of Directive 1999/5/EC.

The conformity assessment procedure referred to in Article 10(3) and detailed in Annex II of Directive 1999/5/EC has been followed.

Network Compatibility Declaration
This equipment is designed to work satisfactorily on all European Union PSTN networks.

This equipment is supplied with a suitable PSTN connector for the country in which it was supplied. If it is required to use this equipment on a different network to the one for which it was supplied, the user is advised to contact the vendor for guidance regarding connection.

USRobotics Corporation
935 National Parkway
Schaumburg, Illinois, 60173
U.S.A

USRobotics Corporation Limited Warranty

This warranty applies to customers located in the United States, Australia, Canada (except Quebec), Ireland, New Zealand, U.K., and other English language countries, and countries for which a translation into the local language is not provided.

56K Message Modem

HARDWARE: USRobotics warrants to the end user (“Customer”) that this hardware product will be free from defects in workmanship and materials, under normal use and service, for the following length of time from the date of purchase from USRobotics or its authorised reseller:

Two (2) years

USRobotics’s sole obligation under this express warranty shall be, at USRobotics’s option and expense, to repair the defective product or part, deliver to Customer an equivalent product or part to replace the defective item, or if neither of the two foregoing options is reasonably available, U.S. Robotics may, in its sole discretion, refund to Customer the purchase price paid for the defective product. All products that are replaced will become the property of USRobotics. Replacement products may be new or reconditioned. USRobotics warrants any replaced or repaired product or part for ninety (90) days from shipment, or the remainder of the initial warranty period, whichever is longer.

SOFTWARE: USRobotics warrants to Customer that each software program licensed from it will perform in substantial conformance to its program specifications, for a period of ninety (90) days from the date of purchase from USRobotics or its authorized reseller. USRobotics warrants the media containing software against failure during the warranty period. No updates are provided. USRobotics’s sole obligation under this express warranty shall be, at USRobotics’s option and expense, to refund the purchase price paid by Customer for any defective software product, or to replace any defective media with software which substantially conforms to applicable USRobotics published specifications. Customer assumes responsibility for the selection of the appropriate applications program and associated reference materials. USRobotics makes no warranty or representation that its software products will meet Customer’s requirements or work in combination with any hardware or applications software products provided by third parties, that the operation of the software products will be uninterrupted or error free, or that all defects in the software products will be corrected. For any third-party products listed in the USRobotics software product documentation or specifications as being compatible, USRobotics will make reasonable efforts to provide compatibility, except where the non-compatibility is caused by a “bug” or defect in the third party's product or from use of the software product not in accordance with USRobotics published specifications or user manual.

THIS USRobotics PRODUCT MAY INCLUDE OR BE BUNDLED WITH THIRD-PARTY SOFTWARE, THE USE OF WHICH IS GOVERNED BY A SEPARATE END USER LICENSE AGREEMENT. THIS USRobotics WARRANTY DOES NOT APPLY TO SUCH THIRD-PARTY SOFTWARE. FOR THE APPLICABLE WARRANTY, PLEASE REFER TO THE END USER LICENSE AGREEMENT GOVERNING THE USE OF SUCH SOFTWARE.

OBTAINING WARRANTY SERVICE: Customer must contact a USRobotics Corporate Service Centre or an Authorized USRobotics Service Centre within the applicable warranty period to obtain warranty service authorization. Dated proof of purchase from USRobotics or its authorized reseller may be required. Products returned to USRobotics Corporate Service Centre must be pre-authorized by USRobotics with a Return Material Authorization (RMA) number or User Service Order (USO) number marked on the outside of the package, and sent prepaid and packaged appropriately for safe shipment, and it is recommended that they be insured or sent by a method that provides for tracking of the package. Responsibility for loss or damage does not transfer to USRobotics until the returned item is received by U.S. Robotics. The repaired or replaced item will be shipped to Customer, at U.S. Robotics’s expense, not later than thirty (30) days after USRobotics receives the defective product.

USRobotics shall not be responsible for any software, firmware, information, or memory data of Customer contained in, stored on, or integrated with any products returned to USRobotics for repair, whether under warranty or not.

WARRANTIES EXCLUSIVE: IF A USRobotics PRODUCT DOES NOT OPERATE AS WARRANTED ABOVE, CUSTOMER'S SOLE REMEDY FOR BREACH OF THAT WARRANTY SHALL BE REPAIR, REPLACEMENT, OR REFUND OF THE PURCHASE PRICE PAID, AT USRobotics’S OPTION. TO THE FULL EXTENT ALLOWED BY LAW, THE FOREGOING WARRANTIES AND REMEDIES ARE EXCLUSIVE AND ARE IN LIEU OF ALL OTHER WARRANTIES, TERMS, OR CONDITIONS, EXPRESS OR IMPLIED, EITHER IN FACT OR BY OPERATION OF LAW, STATUTORY OR OTHERWISE, INCLUDING WARRANTIES, TERMS, OR CONDITIONS OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, SATISFACTORY QUALITY, CORRESPONDENCE WITH DESCRIPTION, AND NON-INFRINGEMENT, ALL OF WHICH ARE EXPRESSLY DISCLAIMED. USRobotics NEITHER ASSUMES NOR AUTHORIZES ANY OTHER PERSON TO ASSUME FOR IT ANY OTHER LIABILITY IN CONNECTION WITH THE SALE, INSTALLATION, MAINTENANCE, OR USE OF ITS PRODUCTS.

USRobotics SHALL NOT BE LIABLE UNDER THIS WARRANTY IF ITS TESTING AND EXAMINATION DISCLOSE THAT THE ALLEGED DEFECT OR MALFUNCTION IN THE PRODUCT DOES NOT EXIST OR WAS CAUSED BY CUSTOMER'S OR ANY THIRD PERSON'S MISUSE, NEGLECT, IMPROPER INSTALLATION OR TESTING, UNAUTHORIZED ATTEMPTS TO OPEN, REPAIR, OR MODIFY THE PRODUCT, OR ANY OTHER CAUSE BEYOND THE RANGE OF THE INTENDED USE, OR BY ACCIDENT, FIRE, LIGHTNING, POWER CUTS OR OUTAGES, OTHER HAZARDS, OR ACTS OF GOD.

LIMITATION OF LIABILITY. TO THE FULL EXTENT ALLOWED BY LAW, USRobotics ALSO EXCLUDES FOR ITSELF AND ITS SUPPLIERS ANY LIABILITY, WHETHER BASED IN CONTRACT OR TORT (INCLUDING NEGLIGENCE), FOR INCIDENTAL, CONSEQUENTIAL, INDIRECT, SPECIAL, OR PUNITIVE DAMAGES OF ANY KIND, OR FOR LOSS OF REVENUE OR PROFITS, LOSS OF BUSINESS, LOSS OF INFORMATION OR DATA, OR OTHER FINANCIAL LOSS ARISING OUT OF OR IN CONNECTION WITH THE SALE, INSTALLATION, MAINTENANCE, USE, PERFORMANCE, FAILURE, OR INTERRUPTION OF ITS PRODUCTS, EVEN IF USRobotics OR ITS AUTHORIZED RESELLER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES, AND LIMITS ITS LIABILITY TO REPAIR, REPLACEMENT, OR REFUND OF THE PURCHASE PRICE PAID, AT U.S. ROBOTICS’S OPTION. THIS DISCLAIMER OF LIABILITY FOR DAMAGES WILL NOT BE AFFECTED IF ANY REMEDY PROVIDED HEREIN SHALL FAIL OF ITS ESSENTIAL PURPOSE.

DISCLAIMER: Some countries, states, or provinces do not allow the exclusion or limitation of implied warranties or the limitation of incidental or consequential damages for certain products supplied to consumers, or the limitation of liability for personal injury, so the above limitations and exclusions may be limited in their application to you. When the implied warranties are not allowed to be excluded in their entirety, they will be limited to the duration of the applicable written warranty. This warranty gives you specific legal rights which may vary depending on local law.

GOVERNING LAW: This Limited Warranty shall be governed by the laws of the State of Illinois, U.S.A. excluding its conflicts of laws principles and excluding the United Nations Convention on Contracts for the International Sale of Goods.

USRobotics Corporation
935 National Parkway
Schaumburg, Illinois, 60173
U.S.A

Contact Details

Support Resources

If you have not fixed your problem after trying the suggestions in the “Troubleshooting” section, you can receive additional help via one of these convenient resources:

Visit the USRobotics Web site

Many of the most common difficulties users experience have been addressed in the FAQ and Troubleshooting Web pages for your specific product. Your product number is 5668B. You may need to know this to obtain information on the U.S. Robotics Web site. Go to: http://www.usr.com/support

Contact the USRobotics Technical Support Department

Technical questions about USRobotics modems can also be answered by technical support specialists.