

                FONIX 6500 RS232 Troubleshooting Guidelines
                                                                 04/30/97


        You should use these guidelines if you are having problems 
        getting your FONIX hearing aid analyzer to communicate with your 
        host computer.  If you are trying to install an RS232 option 
        upgrade, refer to the document titled "RS232 Installation 
        Instructions".

        The most common problems encountered by Frye support personnel 
        are listed below.  It is always best to troubleshoot the most 
        common causes first, before moving on to more complicated causes.  
        For example, if you had the RS232 option installed at the 
        factory, you should start out with the assumption that it has 
        been installed correctly and troubleshoot problems external to 
        the analyzer first.  

        Most common RS232 problems encountered:

        - Customer didn't purchase RS232 but thought they had the option.
        - Bad RS232 cable.
        - Customer had RS232 cable connected to computer COM port 2
          and was trying to communicate with software which was using
          COM port 1 (or vice versa).
        - Customer had multiple COM ports in computer, but they were not
          configured properly on the serial card  (e.g. COM ports were
          not enabled, interrupts conflicted, etc.)
        - Customer installed RS232 option upgrade and didn't connect 
          cables properly inside the analyzer, or didn't install jumper
          correctly.
        - Using the Frye RS232 cable (with the leds) with some laptops
          may not work because the laptop does not provide true RS232 
          output levels.

        To help you troubleshoot the RS232 operation of your FONIX 
        instrument and RS232 software, Frye now supplies the following 
        items with all analyzers which have the RS232 option and with all 
        RS232 option upgrades:

         - Diagnostic plug for your analyzer's serial port.
         - Special RS232 cable with red/green diagnostic LEDs
         - Diagnostic software to check the computer's COM port

        If you purchased your RS232 option before these items became 
        available and you are having trouble with your RS232 operation,
        you should contact Frye to obtain these troubleshooting tools.









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        TROUBLESHOOTING PROCEDURE

        1. Check the analyzer's RS232 option

        When you turn on your analyzer, it checks for RS232 software
        on the system software EPROM.  If it detects the software, it 
        performs a limited self-test of its RS232 hardware.  A status 
        message is displayed below the Frye Electronics copyright notice 
        on the opening display screen.  This message can be any of the 
        following: 

        <no message> -- No RS232 software was detected.  

        This could also indicate bad system software EPROMs, but this is 
        unlikely if the instrument is operating normally in all other 
        functions. Contact Frye to verify that you have the RS232 option 
        or to get replacement EPROMs.  Have your serial number handy. 


        o RS-232 AVAILABLE -- RS232 software was detected and limited
                              diagnostics were passed.


        o RS-232 BAD UART -- RS232 software was detected, but the UART 
                             chip is bad, or is the wrong type, or is 
                             installed incorrectly.  

        If your RS232 option was factory installed, contact Frye.  If you 
        installed the RS232 option yourself, check that none of the pins 
        on the UART chip are bent under or sticking out of the socket on 
        the I/O board.  Check that the notch on the UART chip is toward 
        the top of the I/O board.  Refer to the RS232 installation 
        instructions for more information. If the UART looks like it is 
        installed correctly and you still get above message, contact Frye 
        for a replacement UART or additional help. 

        In addition to the limited self-test described above, you may 
        perform a more detailed check of your RS232 option using the 
        diagnostic plug shipped with your analyzer.  If you did not 
        receive one of these plugs with your instrument, contact Frye to 
        obtain one.

        To perform the detailed RS-232 self-test, turn the analyzer off 
        and insert the 25-pin plug labeled "RS232 Diagnostic Plug" into 
        the 25-pin connector labeled "RS232 Computer Interface" on the 
        back of your analyzer.  Turn the instrument power on.  The 
        analyzer will automatically perform a detailed check of RS232 
        functions.  One of the following status messages will be 
        displayed under the Frye copyright notice: 

        o DIAGNOSTICS PASSED -- Indicates that no problems were detected
                                in your analyzer's RS232 operation. 




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        !!! NOTE !!! 
            If you get any of the following messages with the diagnostic 
            plug installed and your RS232 option was factory installed or 
            installed by a distributor, please contact Frye or the 
            distributor.  Be sure to have your instrument serial number 
            handy when you call.

        o RS-232 AVAILABLE -- RS232 software was detected and the limited
                              self-test passed, but no diagnostic plug 
                              was detected, so no detailed self-test was 
                              performed.  

        If you get this message with the diagnostic plug installed, then 
        the 7-pin RS232 connector on the I/O board inside your instrument 
        is probably misaligned.  Check to make sure that this connector 
        is covering all the connector pins on the I/O board.  Refer to 
        the RS232 installation instructions for more information.  If the 
        connector is correctly installed and you are still getting this 
        message, contact Frye. 

        o RS-232 BAD UART -- Same as described for the limited self-test.


        o RS-232 BAD CABLE --  Indicates that the 7-pin connector on the
                               I/O board is installed upside down. 

        When this connector is correctly installed, the white dot on the 
        connector is toward the bottom of the I/O board and the gray wire 
        on the ribbon cable is toward the top.  If the connector is 
        installed correctly and you still get this message, contact Frye. 


        o RS232 NO INTERRUPT -- Indicates that the jumper next to the 
                                UART on the I/O board is connected 
                                incorrectly or the run has not been cut.

        You should refer to the RS232 installation instructions for 
        correct jumper installation. If the IO board was an old style 
        board, it may also require that the run under the jumper be cut. 
        This should have been done during installation. (Note: The cut 
        run applies only to old style IO boards.)  















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        2. Check that the analyzer is sending polls

        When the analyzer is ready to accept commands from the computer 
        it sends a stream of special data packets, called "polls", to the 
        computer, usually about 5 times per second.  To determine if the 
        analyzer is sending polls, connect the Frye RS232 cable with the 
        red and green LEDs between the analyzer and the computer (the 
        LEDs go on the computer end) and reset the analyzer. The analyzer 
        will come up with the opening logo screen and begin  sending 
        polls.  You should see a flickering red LED on the RS232 cable to 
        indicate that polls are being sent down the cable.  If you do not 
        see the red LED flickering, there is a problem with your analyzer 
        (or your test cable is bad). 

        Note:  If you do not have the Frye cable, but you have an 
        oscilloscope handy, you can use the scope to look for pulses on 
        pin 3 of the 25-pin connector or pin 2 of the 9-pin connector. 

        If your analyzer is sending polls and you are not communicating,
        you can assume the analyzer is functioning properly and look 
        for problems in the cable or computer.


        3. Check the RS232 cabling

        A bad RS232 cable is often the cause of communication problems
        between an analyzer and computer, particularly if the problem 
        seems to be intermittent.  The quickest way to check for a bad 
        cable is to try a known good cable.  If you don't have a cable 
        that you are sure is good, you may want to purchase a new one.  
        The odds of the new cable being bad are slight, so if you still 
        have the problem after trying a new cable, you can assume that 
        the problem is in the computer or application software. 

        The Fonix RS232 option expects a standard 'straight-thru' RS232 
        cable. These cables are available from most stores that carry 
        computer supplies.  If you want to use a longer cable, the RS232 
        standard supports cable lengths up to 50 feet at the 
        communication rate used by FONIX instruments, but you can 
        probably go up to 100 feet without having any problems.  Do not 
        use RS232 cables which are designated as "Null Modem" cables.  
        Your computer's serial port connector may be either 9-pin or 25-
        pin connector (or you may have both types). You may connect your 
        analyzer to either of these ports.  You may use a standard 25-
        pin-to-9-pin adapter to adapt the Frye RS232 cable (or any other 
        standard 25-pin RS232 cable) to use the 9-pin port. 










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        4. Check the computer's serial port

        Most computers have one 25-pin female parallel port and one or 
        two male 25-pin or 9-pin serial ports.  With few exceptions you 
        can identify the serial ports by looking for 25-pin or 9-pin 
        connectors on the back of your computer which are male (they have 
        pins sticking out).  The serial card(s) in your machine usually 
        have jumpers which disable or enable these ports and jumpers to 
        determine which connector gets assigned to which communications 
        port: COM1, COM2, COM3, or COM4.  If you have two COM ports, they 
        are almost always configured as COM1 and COM2 at the factory or 
        at the computer store.  It is important for you to determine 
        which COM port has been assigned to each connector so that you 
        are not trying to communicate with COM1 when you are connected to 
        COM2.  Some computers have these ports labeled, but most don't.  
        You can usually look at your computer documentation or the 
        documentation that came with your serial cards to determine this 
        information, but often it is easier to just run some program 
        which uses the serial ports and figure out which port works when 
        you have the software configured for that port.  This is the 
        approach we have taken with the RS232 diagnostic program. 

        Your RS232 diskette contains a program called FCHECK.EXE which
        checks a several functions of your RS232 communication from 
        the computer side.  To use FCHECK, you should have your computer 
        and analyzer connected with an RS232 cable.  Reset your analyzer 
        so it is in the opening screen sending polls. If you have the 
        Frye RS232 cable, you should check the red LED to make sure you 
        are receiving polls as described above. 

        In order to run FCHECK on an MSDOS or Win3.1 system, you must 
        first load the FRYERS.COM driver.  Load FRYERS and then start 
        FCHECK. FCHECK will start up and begin testing COM1 by default. 
        For 32 bit systems (Win95 or WinNT), you should run FCHECK32. 
        FCHECK32 does not use FRYERS.COM, but it does need FRYERS32.DLL 
        to be located in the Windows subdirectory.

        When FCHECK starts, the Status box in the upper right hand corner 
        will display the message "-- Testing --".   Eventually this 
        status box will display either the message "No Poll" or the 
        message "Test Completed".

        A "No Poll" message indicates that the computer is not receiving 
        polls from the analyzer on COM1.  If you see pulses on the red 
        LED, you know you are getting polls, so you can assume that the 
        port you are connected to on the back of the computer is not 
        COM1, or that COM1 is disabled or malfunctioning.  The Help 
        window describes error conditions that might be causing the 
        problem.  







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        A "Test Completed" status message should be accompanied by a
        message in the Help window saying that RS232 communication on 
        COM1 is functioning successfully.  If you get this message, then 
        you have a functioning communications link via the Fryers FIPP
        protocol between the analyzer and the computer.  If your 
        application still isn't working, you probably have an error in 
        your application.  If your application can be configured to use 
        COM1 or COM2, such as the Frye CHAP program, you should check to 
        make sure that the program is configured for the correct port. 

        If you receive a 'No Poll' on COM1, press '2' to begin testing
        COM2.  Do not change the connection on the back of your computer.
        If you get a successful connection, you know that the connector 
        you are currently connected to on the back of the computer is 
        COM2.  If you get a 'No Poll' on COM2 as well, you know that the 
        port is disabled, or malfunctioning, or is configured as COM3 or 
        COM4.  To test for COM3, press "3". To test for COM4, press "4". 
        If you cannot get a successful communication using FCHECK, then 
        you most likely have a malfunctioning or incorrectly configured 
        serial card.  

        Note: Sometimes the COM ports use non-standard interrupts. This 
        is sometimes done to allow more than the two standard COM ports 
        to exist in the computer. If you know the interrupt number for 
        the card, you can set it by pressing "I" followed by the 
        interrupt number (use "A" through "F" for interrupts 10-15). 
        During startup of the test, FCHECK will look for the available 
        valid interrupts (on 16 bit systems only). 

        Note: Some laptops do not provide a full RS232 compatible output. 
        This may cause a problem if you are using the Frye supplied RS232 
        cable with the red and green leds. If you are using a laptop, try 
        replacing the Frye supplied cable with a standard RS232 cable 
        (without the leds). 

          
        5. If you have performed all the checks in steps 1 through 4 and 
        still cannot get the computer to communicate with your analyzer, 
        call Frye for additional help. 
                 
        History: 09/27/94 -med original
                 04/30/97 -med revised 

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