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   The following information can help you solve certain problems with your
   Intel product.  "(Field report)" means that the information comes from a
   customer and may not have been verified by Intel's compatibility lab.


   ARE YOU ON A PBX PHONE SYSTEM?

       If your modem loses data or has degraded performance, it could be
       because it's connected to a PBX telephone system.  Check with the phone
       company to determine if you're connected to a PBX or other phone system
       that requires a special digit to dial out.


   CARRIER ALREADY ESTABLISHED MESSAGE

       If you receive this message before the modem dials the phone number,
       use a communication program or TESTCOM to change the values of Data
       Carrier Detect (DCD) and Data Terminal Ready (DTR).  Intel sets these
       signals to 0 on non-MNP modems (2400B Calssic, 2400EX, and CCP Modem
       Option) to match the Hayes default, but many communication programs
       require a value of 1 to work.  The 2400B Classic MNP, 2400EX MNP, and
       9600EX

       If you use TESTCOM, select 6 from the main menu.  This allows you to
       use the Hayes command set to address the modem hardware.  You can also
       enter the following line at a place in your modem software that
       responds to the Hayes AT Command Set:

           AT&C1&D2&W

       The C1 changes the DCD to 1, the D2 changes the DTR to 2, and the W
       writes the information into modem memory.


   DETECTING PORTS WITH DEBUG

       If you're having a problem determining which parallel and serial ports
       your computer is using, you can check for the I/O ports using the DEBUG
       program.  Follow these steps to use DEBUG:

       1.  At the DOS prompt, type DEBUG and press Enter.

       2.  At the DEBUG prompt (a dash), type D 40:0 and press Enter.  This
           displays the hexadecimal codes of the active I/O ports, first
           serial then parallel:

               0040:0000  F8 03 00 00 00 00 00 00-BC 03 00 00 00 00 00 00

           This display indicates one serial port installed at 3F8 and one
           parallel port installed at 3BC.  (Note that the high and low bytes
           are reversed.)

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       3.  To quit DEBUG, type q and press Enter.


   INTERMITTENT SWITCH TO COMMAND MODE

       If your modem intermittently switches to Command mode after connecting
       with a remote system, change the DTR option to &D2 with this command:

           AT&D2


   LEASED LINE SETUP

       If modems fail to communicate over leased lines, but work fine on
       standard lines, change the &L setting to &L1.  The default setting is
       &L0.  See your modem command guide for more information.

       In addition, if the leased line is a 4-wire line rather than a 2-wire
       line, a 4-wire to 2-wire converter will be required.  This converter is
       often a simple switch on the leased line telephone equipment in your
       office.


   MODEM DIALS BUT DOES NOT CONNECT

       Communications software has each of the COM ports configured for a
       specific I/O address and IRQ combination.  If the modem and software
       configurations do not match exactly, the modem may dial but be unable
       to signal the computer that it has achieved a connection.  Compare your
       modem I/O and IRQ settings to those in your software to ensure an exact
       match.

       This problem may also appear when there is another device using the
       same IRQ as the modem.  Adjust the modem and conflicting device to
       different IRQ settings so they no longer conflict.


   NO DIALTONE MESSAGE

       Some computers (typically mainframes) require that modems call once,
       hang up, wait for a return call, and then call again (using ATD).  With
       2400B modems, when the modem picks up the phone to dial the second
       time, it detects no dialtone and hangs up.  To avoid the problem, type
       this command:

           ATX3&W

       then press Enter.  This suppresses the NO DIALTONE result code allowing
       the modem to connect.

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   PHONE LINES ATTACHED CORRECTLY?

       Your modem won't work if the phone lines are connected incorrectly to
       the back of the modem.  The connector marked "line" for the phone line
       coming from the wall, and the one marked "phone" is for the phone line
       going to the telephone.  Neither the computer nor the modem need to be
       turned on to use the phone for normal voice calls.










































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