Installing the 3Com Impact Digital Modem 2-3 Installing the Digital Modem in an IBM-compatible PC 2-3 Installing the Digital Modem in an Apple Macintosh Computer 2-4 Configuring the 3Com Impact Digital Modem 2-6 Configuration for IBM PC or Compatible Computer 2-7 Configuration for Apple Macintosh Computer 2-13...
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Receiving Calls Using the Phone Out Port 2-18 Protocol Support 2-19 Async-Sync PPP Conversion 2-19 QuickSelect 2-19 ROUBLESHOOTING Troubleshooting Tips 3-1 Downloading Firmware to Your External Digital Modem 3-5 AT C OMMAND AT C OMMANDS AT Command Set for the 3Com Impact...
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IGURES 1-1 Analog and Digital Network Access with the 3Com Impact Digital Modem 1-2 2-1 Back Panel Power Switch and Connectors 2-1 2-2 Front Panel LED Indicators 2-1 2-3 Configuration Dialog Box 2-8...
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1-2 Pin Descriptions 1-9 2-1 Front Panel LED Indicator Definitions 2-2 B-1 AT Command Set Summary B-1 B-2 AT Command Set Summary for the Internal Analog Modem B-4 B-3 Remote S Registers B-7 B-4 3Com Impact Digital Modem Result Codes B-10...
Introduction This guide describes how to install, operate, and troubleshoot the 3Com Modem, referred to throughout this guide as the 3Com Impact digital modem. If the information in the release notes shipped with your product differs from the information in this guide, follow the release notes.
BOUT UIDE Conventions Table 1 and Table 2 list text and icon conventions that are used throughout this guide: Table 1 Text Conventions Convention Description Text represented as This typeface is used to represent displays that appear on your terminal screen, for example: screen display NetLogin:...
NTRODUCTION The Integrated Services Digital Network (ISDN) is a digital communications standard for supporting voice, data, and video applications through conventional telephone wires. Specifically, ISDN is a method of connecting to the public telephone network using digital technology. ISDN uses the existing copper wire and public telephone network infrastructure.
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® ISDN line Figure 1-1 Analog and Digital Network Access with the 3Com Impact Digital Modem Four models of the 3Com Impact digital modem are sold in the U.S. and Canada: 3C871 is the IBM modem product. 3C872 is the IBM or IBM-compatible PC external digital modem product with an internal 14.4 Kbps analog fax...
3Com Impact Digital Modem Features The 3Com Impact digital modem can be connected to any â â compatible UL -listed IBM AT -compatible or Apple Macintosh personal computer that includes instructions for the installation of hardware and software options to serial ports.
Access and download graphics, software, and data files more quickly Voice Capabilities The 3Com Impact digital modem’s Phone Out port allows the use of existing analog telephone equipment (touch-tone telephones, cordless telephones, and fax and answering machines) to place and receive calls over the ISDN line. When you connect to another ISDN line, setup times are reduced, and voice quality is excellent.
Analog Modem Capabilities The 3Com Impact digital modem (models 3C872 and 3C877) includes an integrated V.32bis analog modem for data or fax transmissions of up to 14.4 Kbps over the ISDN line. V.42bis data compression boosts analog modem throughput to up to 57.6 Kbps.
3Com has determined the optimal ISDN line configurations for the 3Com Impact digital modem and has provided that configuration data to many telephone companies. To simplify the ordering process for an ISDN digital line, use the following simplified ISDN ordering code:...
Connect the model 3C871 or 3C872 3Com Impact digital modem to an IBM-compatible computer. Connect the model 3C876 or 3C877 3Com Impact digital modem to an Apple Macintosh computer. Connect the digital modem to a computer that meets UL standards in the United States or is certified to CSA standards in Canada.
Microsoft In addition, for reliable high-speed serial port performance in the Microsoft Windows environment, a TurboCom Windows, which replaces the standard Microsoft Windows COM driver, is included with the 3Com Impact digital modem. â MS-DOS 640 Kilobytes of conventional memory Microsoft Windows 3.1 or later (optional)
Cabling Requirements Cables to connect the 3Com Impact digital modem to your computer are provided. For IBM or IBM-compatible PCs with a 25-pin serial port, a DB-9–to–DB-25 connection adapter is included with the digital modem. The asynchronous RS-232-C port on the digital modem, labeled Computer, is a standard DB-9 female connector.
NSTALLING AND ONFIGURING This chapter describes installation and configuration of the 3Com Impact digital modem. In combination with the instructions given in this chapter, follow the instructions given in the appropriate PC or Macintosh computer user guide. Refer to Figure 2-1 and Figure 2-2, showing the digital modem back and front panels, during installation and configuration.
Test Yellow Self-Test/Status. Flashes when the digital modem is executing its power-up self-test or a user-initiated reset. If the results of the self-test or reset are normal, the LED goes off. If the result of the self-test is abnormal and a fault is detected, the LED remains lit but does not flash.
RS-232-C. On an IBM AT PC and most laptops or notebooks, connect the cable to a 9-pin COM port connector. 5 Connect the 3Com Impact digital modem power cable to the connector marked 12V AC on the back panel of the digital modem.
Basic Rate ISDN 2B1Q U Interface network terminations. An internal Network Termination device (NT1) is built into the digital modem. Do not connect the 3Com Impact digital modem ISDN port to a standard analog telephone jack or to an external NT1 device. Make sure that it is connected to the ISDN jack.
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Basic Rate ISDN 2B1Q U Interface network terminations. An internal Network Termination device (NT1) is built into the digital modem. Do not connect the 3Com Impact digital modem ISDN port to a standard analog telephone jack or to an external NT1 device. Make...
2: I HAPTER NSTALLING AND 9 Turn on the 3Com Impact digital modem by toggling the power switch on the back panel to the On position. See Figure 2-1 for the location of the power switch on the digital modem’s back panel. The indicator LEDs on the front panel (see Figure 2-2) flash momentarily as the unit...
After you configure the digital modem and verify that it is working properly, you should install the TurboCom software. Refer to the installation instructions that came with the TurboCom software. This software is required only for IBM PC or compatible computers running Windows 3.X.
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ISDN telephone line, for example, a message indicates this condition. The right side of the dialog box shows the digital modem software version, along with any installed options (such as Multilink PPP or internal analog fax modem).
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fields in the Number 2 area. 10 Specify which device should receive the calls coming to Telephone Number 2. 11 Click the Configure button to download the parameters listed in steps 5 through 10 to your digital modem’s S registers.
After the TurboCom software is installed, proceed to the “Placing and Receiving Calls” section. Configuration Using DOS To configure the digital modem for an IBM PC or compatible computer using DOS: 1 Create a directory on the hard drive, insert the 3Com Impact DOS &...
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The program does not allow you to select a data rate that exceeds the speed of your COM port. 4 Press [F10] to connect to the 3Com Impact digital modem via the chosen COM port. The Configuration screen will appear.
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When these parameters are updated, the information is read back to the screen. Check to see that the values have been correctly entered. 11 Press [F10] to update the information in the 3Com Impact digital modem. ONFIGURING THE IGITAL...
12 Reset the digital modem by turning the power switch off and then on again. If the parameters match those registered at the telephone company ISDN switch, the D channel LED lights for a few minutes, flashes for several seconds, and then turns off. If the LED continues to flash or remains lit, see Chapter 3,...
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9 Click the Update Configuration button to update this information to the 3Com Impact digital modem. 10 Reset the digital modem by turning the power switch off and then on again. If the parameters match those registered at the telephone company ISDN switch, the D channel LED lights for a few minutes, flashes for several seconds, and then turns off.
Placing and Receiving Calls This section illustrates how to place and receive a variety of calls with your 3Com Impact digital modem. The digital modem uses AT commands and S registers for call management. See Appendix A, “AT Command Set Overview,”...
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ONFIGURING THE IGITAL ODEM By default, the 3Com Impact digital modem dials the same number for both Multilink PPP channels. If the destination to which the digital modem is dialing to establish a second Multilink PPP channel requires a different telephone number, then this second telephone number is stored in register S81.
If auto answer is disabled (the default) in register S0, a RING message is delivered to the Computer port upon reception of an incoming data call to the digital modem. The command AT A answers the incoming data call. A CONNECT message is then delivered to the Computer port upon successful connection.
Specialized telephone equipment, most notably speaker phones that draw significantly larger amounts of power, may not work at all on the digital modem’s Phone Out port. These devices do not conform to the loop current (power) specification of the 2500 touch-tone telephone standard, and their operation is not guaranteed.
Protocol Support Async-Sync PPP Conversion One of the most unique and powerful features of the 3Com Impact digital modem is its ability to convert asynchronous Point-to-Point Protocol (PPP) into synchronous (HDLC-based) PPP that can be transported in ISDN B channels to communications servers and routers that have integrated ISDN Basic Rate (BRI), Primary Rate (PRI), or T1 access lines.
1 The power supply is connected and the power LED is on. 2 Turn the 3Com Impact digital modem power switch off and then on again several times and observe the Test LED. During power-up self-test, the Test LED flashes.
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(an NT1 device is not required with this digital modem). 4 Make sure that the cables provided by 3Com or a 3Com authorized reseller are in good condition and show no evidence of wear or other physical damage.
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If the D channel LED goes out, the digital modem is ready to place and receive calls. If you have a standard analog telephone attached to the digital modem’s analog voice port, you can place a voice...
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B channel call data rate is the same as the remote destination call data rate. The default B channel data rate used by the digital modem is 56 Kbps. Under some circumstances, the data rate may be...
As recommended by 3Com technical support, you may need to download the latest firmware to your digital modem. You can use the following procedure to download the updated firmware to your digital modem.
For Macintosh Computers This section provides instructions on downloading firmware from your Macintosh to your digital modem. 1 Obtain the latest firmware file from the 3Com FTP site ftp.3Com.com. 2 Copy the firmware file to your computer. 3 Double-click the 3Com Impact icon to access the Utility dialog box.
AT V1 D 1 800 555 3333 [Enter] AT gets the attention of your 3Com Impact digital modem. V1 sets the digital modem to verbose mode so that it sends its responses in English words instead of numbers. D tells the digital modem to dial an ISDN digital connection to the phone number that follows.
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When your computer is powered on, the digital modem automatically starts in command mode. If you have recently used the digital modem to make a call and have not yet disconnected, type +++ to switch to command mode. 3 Type: AT <commands>...
AT C The 3Com Impact ISDN digital modem commands are summarized in Table B-1, modem commands for the internal analog modem in Table B-1, remote S registers in Table B-3, and digital modem result codes in Table B-4. AT Command Set for the 3Com Impact Digital Modem Table B-1 summarizes the AT command set.
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I4 displays the modem product code, precomputed checksum, firmware revision number, model, interface type, country code, and data pump model. Causes the digital modem to go out of command mode into on-line mode. Q0 enables the output of result codes (default).
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AT Command Set for the 3Com Impact Digital Modem Table B-1 AT Command Set Summary (continued) Command Function (Example) Read on-line status: command settings (AT \S) Link inactivity timer (AT \T1) Result code format (AT V0) &W Stores configuration (AT &W)
B: AT C PPENDIX AT Command Set for Internal Analog Fax Modem Table B-1 summarizes the AT command set for the internal analog modem. Table B-2 AT Command Set Summary for the Internal Analog Modem Command Function (Example) Set 1200 bps (operation= 0) ATC1 Select modem modulation mode 0 —...
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Table B-2 AT Command Set Summary for the Internal Analog Modem (continued) Command Function (Example) Select the subset of result messages that will be used by the modem to inform the PC of the results of commands Line quality monitor control Return received line signal level Report line signal quality &G...
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B: AT C PPENDIX Table B-2 AT Command Set Summary for the Internal Analog Modem (continued) Command Function (Example) Set preferred error-correcting mode to be negotiated in a subsequent data connection MNP extended services MNP 10 fallback to 2400 bps (V.22bis)/1200 (V.22) Link negotiation speed All fax commands (AT+fax sub-...
Remote S Registers The 3Com Impact digital modem supports the S registers listed in Table B-3. All S registers except S0 are the 3Com extended registers. Table B-3 Remote S Registers Registers (continued) Descriptions Auto Answer 0 — Disabled (default) 1 —...
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Indicates the status of the second TEI using SPID 2. This information is provided only if your carrier requires a second directory number. This field is read-only. 0 — 3Com Impact digital modem has not attempted initialization 1 — 3Com Impact digital modem has initialized successfully using SPID 2 2 —...
B-10 B: AT C PPENDIX Digital Modem Result Codes Table B-4 lists the 3Com Impact digital modem result codes. Table B-4 3Com Impact Digital Modem Result Codes Short Form Long Form RING NO CARRIER ERROR BUSY CONNECT 1200 CONNECT 2400...
Ask3Com 3ComFacts 3Com Bulletin Board Service 3ComBBS contains patches, software, and drivers for all 3Com products, as well as technical articles. This service is available via modem seven days a week, 24 hours a day. To reach the service, set your modem to 8 data, no parity, and 1 stop bit.
C: T PPENDIX ECHNICAL World Wide Web Site Access the latest networking information on 3Com’s World Wide Web site by entering our URL into your Internet browser: http://www.3Com.com/ This service features news and information about 3Com products, customer service and support, 3Com’s latest news releases, selected articles from 3TECH award-winning technical journal, and more.
NetFacts provides data sheets and technical articles on 3Com Corporation’s hub, bridge, router, terminal server, and software products. Document 8888 provides you with an index of system product documents. Call 3ComFacts using your touch-tone telephone. International access numbers are: Local access numbers are available within the following...
In the U.S. and Canada, call (800) 876 3266 for customer service. Returning Products for Repair A product sent directly to 3Com for repair must first be assigned a Return Materials Authorization (RMA) number. A product sent to 3Com without an RMA number will be returned to the sender unopened, at the sender’s expense.
Other hardware products Spare parts and spares kits If a product does not operate as warranted during the applicable warranty period, 3Com shall, at its option and expense, repair the defective product or part, deliver to Customer an equivalent product or part to replace the defective item, or refund to Customer the purchase price paid for the defective product.
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AUTHORIZES ANY OTHER PERSON TO ASSUME FOR IT ANY OTHER LIABILITY IN CONNECTION WITH THE SALE, INSTALLATION, MAINTENANCE OR USE OF ITS PRODUCTS. 3COM SHALL NOT BE LIABLE UNDER THIS WARRANTY IF ITS TESTING AND EXAMINATION DISCLOSE THAT THE ALLEGED DEFECT IN THE PRODUCT DOES NOT EXIST OR WAS CAUSED BY...
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This booklet is available from the U.S. Government Printing Office, Washington, D.C. 20402. Stock No. 004-000-00345-4. NOTE: In order to maintain compliance with the limits of a Class B digital device, 3Com requires that you use quality interface cables when connecting to this device. Changes or modifications not expressly approved by 3Com could void the user’s authority to operate this equipment.
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CANADIAN NOTICE The Industry Canada label identifies certified equipment. This certification means that the equipment meets certain telecommunications network protective, operation, and safety requirements. The Department does not guarantee the equipment will operate to the users’ satisfaction. Before installing this equipment, users should ensure that is permissible to be connected to the facilities of the local telecommunications company.
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