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   |      Troubleshooting the Intel 2400B Classic and 2400EX Modems          |
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    MODEM WON'T HANG UP PHONE/"HANGUP FAILED"

        On a PC based system, issue "AT&C1&D2&W" in termianl mode. Setting &D2
        will cause the modem to hang up the phone when DTR is lost. In non-MNP
        Intel modems, the default is &D0 (as is Hayes), which causes the modem
        to ignore the DTR signal normally used by terminal packages to tell the
        modem to hang up the phone.


    MODEM WON'T STORE PHONE NUMBERS

        In Intel MNP based modems (SatisFAXtion and 9600EX included), 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).

        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).

        The 9600EX with ROM Version 1.00 and 1.01 had a problem with storing
        numbers. If the customer is having trouble storing telephone numbers,
        check the ROM version with the ATI3 command and send the latest ROM
        from FSI.


    NO DIALTONE RESULT CODE

        There are four common causes for this error:

        -   The telephone line from the wall is plugged into the "phone" jack
            instead of the "line" jack. The line from the wall needs to be
            plugged into "line".

        -   Using a CCP modem option with CCAM not loaded. The CCP modem option
            REQUIRESthat CCAM and CONNECT.SYS are loaded before the modem can
            be used. CCAM Has control of the board's fax/modem relay. Without
            CCAM, the modem can't be switched in to use the phone line. The
            same holds true for the SatisFAXtion board. Both drivers
            (SATISFAX.SYS and CASMGR.EXE) must be present for the modem to
            work.

        -   Digital phone systems. See "Are you on a digital phone system?"
            cell.







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        -   Multi line telephones. Sometimes there are RJ-11 jacks that house
            two separate telephone numbers. Our modems (as do all) use pins 2&3
            on the RJ-11 for signal. Two line RJ-11 jacks use pins 1&2 for line
            1 and pins 3&4 for line 2. If the customer has this type of phone
            system, a 2 line to 1 line converter is needed - NOT A Y CONNECTOR.
            You can identify a two line phone by "line 1/line 2" buttons on the
            telephone that it's plugged into.


    PHONE LINES ATTACHED CORRECTLY?

        Your modem may or may not work (or work erratically) if the phone lines
        are connected incorrectly to the back of the modem. The connector
        marked "line" is 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 have to be on to use the phone for normal
        voice calls.


    REMOTE SYSTEM GIVES GARBAGE, HANGS UP

        Some systems *REQUIRE* that you have an MNP modem to connect. The
        answer modem will attempt to make an MNP connection. When it fails, it
        will disconnect. Make sure you issue "AT\N3" to enable MNP. THIS IS NOT
        THE DEFAULT FOR 2400EX MNP OR 2400B MNP.


    SERIAL PORTS & INTERRUPTS - STANDARDS

        Classic        Addr    IRQ          Micro Channel   Addr    IRQ
        -------        -----  -----         -------------   -----   -----
        COM 1          03f8h  IRQ 4         Serial 1        03f8h   IRQ 4
        COM 2          02f8h  IRQ 3         Serial 2        02f8h   IRQ 3
        COM 3          03e8h  IRQ 4/5*      Serial 3        3220h   IRQ 3
        COM 4          02e8h  IRQ 3/2*      Serial 4        3228h   IRQ 3
                                            Serial 5        4220h   IRQ 3
                                            Serial 6        4228h   IRQ 3
                                            Serial 7        5220h   IRQ 3
                                            Serial 8        5228h   IRQ 3

        * COM 3 and COM 4 in classic bus computers are not IBM standards, but
        defacto standards widely accepted by modem and system manufacturers.


    SERIAL PORTS & INTERRUPTS - INTERNAL MODEMS

        2400B Classic, 2400B MNP - Classic bus based:

        COM 1 IRQ 4 - COM 2 IRQ 3 - COM 3 IRQ 4 - COM 4 IRQ 3
        COM 3 IRQ 5 and COM 4 IRQ 2 are not supported by this modem!

        2400B Modem 2 - Micro Channel bus based: Standard Serial 1-8

        SatisFAXtion modem and CCP:

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   |      Troubleshooting the Intel 2400B Classic and 2400EX Modems          |
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        COM 1 IRQ 4 - COM 2 IRQ 3 - COM 3 IRQ 4/5 - COM 4 IRQ 3/2


    S7 REGISTER LIMITS

        The modem command guide incorrectly states that our modems have a limit
        of 30 seconds for S7. The S7 register supports up to 255 seconds.

        ** INTEL CONFIDENTIAL **

        The only exception to this rule is version 1.5 of our non-MNP chipset
        that DOES have a 30 second limit. This would affect the 2400B Classic,
        2400EX, the Connection Co-Processor modem, and the 2400B Modem 2.
        Version 1.6 and newer support a range of 1-255 seconds for the S7
        register. Here's how to test the presence of version 1.5:

        - Issue ATZ to the modem and wait for an OK.
        - Issue ATS7=75 and wait for an OK.
        - Issue ATS7? and observe the result.

        If the returned value is 030, the modem is version 1.5. If the value is
        075 the modem is version 1.6 or newer.

        If a customer is specifically having problems with the 30 second time
        limit for the S7 register and you've verified that they do have version
        1.5 of the modem chipset, RMA their modem for a new one. All currently
        shipping non-MNP modems have version 1.6 or higher chipsets.

        NOTE: This problem only appears (if at all) in the 2400EX, 2400B
        Classic, 2400B Modem 2 or the Connection Co-Processor modem option. MNP
        BASED MODEMS ARE NOT AFFECTED.


    TESTCOM PASSES -- OTHER PROGRAMS FAIL

        THIS CELL PERTAINS ONLY TO TESTCOM VERSIONS PRIOR TO 4.0!!

        Since the older version of TESTCOM doesn't use interrupts when
        diagnosing the modem, IRQ conflicts and/or COM port overlaps may not
        surface.

        If TESTCOM works fine, suspect an IRQ conflict or COM port overlap and
        troubleshoot accordingly.


    TESTCOM LOCKS SYSTEM WHEN TESTING SATISFAXTION MODEM

        This is caused by a COM port overlap or the SatisFAXtion device drivers
        not being loaded. Both SATISFAX.SYS AND CASMGR need to be loaded for
        the modem to operate properly. TESTCOM Version 4 and newer will not
        lock but report an error.

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   |      Troubleshooting the Intel 2400B Classic and 2400EX Modems          |
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   |============================== (continued) ==============================|

        The SatisFAXtion modem manual indicates that the machine should be
        booted to a clean floppy (with no AUTOEXEC/CONFIG) before running
        TESTCOM. THIS IS INCORRECT.Boot normally and ensure that SATISFAX.SYS
        and CASMGR are installed before running TESTCOM!


    &V COMMAND RETURNS "ERROR"

        Intel's 2400B MNP and 2400EX MNP modems use "AT\S" instead to view the
        modem's status instead of AT&V. All other MNP based modems use AT&V.


    XENIX/UNIX AUTO-ANSWER PROBLEMS

        If the customer is having trouble with their modem auto answering
        (Unix/Xenix based system), the modem may need to be setup to be in
        "quiet" mode. Most Xenix/Unix systems don't look for RING or CONNECT
        result codes. They will be interpreted as login attempts. Try issuing
        "ATS0=1E0Q1&W" to the modem. After sending this command to the modem,
        the AA light should come on and no response should be given on the
        screen. It will shut off echo, turn off modem result codes and answer
        the phone on the first ring. This command sequence will also write this
        configuration into the modem's non-volatile RAM, so every time the
        modem is turned on these settings will be retained.




























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