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   |        TROUBLESHOOTING THE INTEL 2400B MNP AND 2400EX MNP MODEMS        |
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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.


   GENERAL MNP PROBLEMS
   --------------------

   MNP DOESN'T WORK WITH UNIX/XENIX UUCP

       Having MNP enabled during Unix/Xenix UUCP file transfers will cause
       numerous data errors, slow throughput, and, in most cases, a complete
       shutdown of the transfer.  This is because UUCP is a complex packet
       switching protocol that is extremely time sensitive.  MNP causes
       several data stream "bursts" that will destroy UUCP connections.  Santa
       Cruz Operation, makers of SCO Xenix, recommends not using MNP with
       UUCP.

   MODEM APPEARS TO BE LOCKED UP


       CAUSE:  This can happen in MNP modems when flow control is set ON.
               Symptoms include sudden halts or excessive timeouts during
               binary or ASCII file transmissions and data going from the
               computer to the modem but never reaching the remote modem.

       CURE:   Before dialing a BBS (or mainframe) issue the command
               "AT\Q0\G0". This command turns off all flow control.  Don't
               confuse the "\Q0" with command with the "Q0" command.  They
               serve completely different functions.  Read you modem command
               guide for more details.


   MODEM SUDDENLY DISCONNECTS

       CAUSE:  Intel MNP modems have an inactivity timer which hangs up after
               a predetermined number of munites pass with no data sent or
               received.  The remote modem disconnecting or a noisy could also
               cause the modem to hang up.

       CURE:   Disable the inactivity timer using the command "AT\T0".


   MODEM WON'T STORE PHONE NUMBERS

       CAUSE:  In Intel MNP modems, you can store up to 4 phone numbers using
               the AT&Z command.  However, the description of the command in
               the documentation is not correct (Modem Command Guide
               #301652-002).

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   |        TROUBLESHOOTING THE INTEL 2400B MNP AND 2400EX MNP MODEMS        |
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       CURE:   The correct command is  AT&Zn=XXXXXXXXX   (where n=0-3 and X's
               represent any character you would normally include after the D
               in an ATD command).  To dial a number that has already been
               stored, use  ATDSn  or ATDS=n  (where n=0-3).

       For example, to store "T9,645-6275" in register 2, type
       AT&Z2=T9,645-6275  then press the enter key.  To dial the stored
       number, type  ATDS=2  then press enter.


   REMOTE COMPUTER DOESN'T RESPOND TO COMMANDS

       CAUSE:  This can happen in MNP modems when flow control is set ON.
               Symptoms include sudden halts or excessive timeouts during
               binary or ASCII file transmissions and data going from the
               computer to the modem but never reaching the remote modem.

       CURE:   Before dialing a BBS (or mainframe) issue the command
               "AT\Q0\G0". This command turns off all flow control.  Don't
               confuse the "\Q0" with command with the "Q0" command.  They
               serve completely different functions.  Read you modem command
               guide for more details.


   &V COMMAND NOT SUPPORTED

       CAUSE:  Intel modems do not support the &V command which dumps the
               modem settings to the screen.

       CURE:   Use the  \S  command instead.


   2400EX MNP
   ----------
   MR LED STEADY ON

       The Intel 2400EX and 2400EX MNP manuals incorrectly state, "If the MR
       light stays ON, the modem isn't working".  The correct statement  is,
       "If the MR light is FLASHING constantly, the modem isn't working".
       Intel has printed an errata to correct the error.









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