

                                                           04/04/97 -med

                FONIX FP40 RS232 Troubleshooting Guidelines


        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 in the instrument but did 
          something wrong during the installtion.
        - 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 the analyzers which have the RS232 option and with the 
        RS232 option upgrades:

         - Special RS232 cable with red/green diagnostic LEDs
         - Diagnostic software to check the computer's serial 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
                              RS232 diagnostics were passed.


        o RS-232 BAD UART -- RS232 software was detected, but the 
                             hardware is bad.

        If your RS232 option was factory installed, contact Frye.  
        Refer to the RS232 installation instructions for more 
        information. 

        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). 




















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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.  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. Run the FCHECK program on the computer. 
        Refer to the FCHECK documentation for more information on the use 
        of the FCHECK program.

        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 may be a problem 
        with your analyzer (or your test cable is bad). Note: If the 
        FRYERS driver has not been run on the computer, or the FCHECK 
        program is not running, you may not see the red led flashing. 
        The FP40 requires that a program is running on the PC that 
        enables the RS232 operation before it will send polls. 

        If you do not have the Frye cable, but you have an oscilloscope 
        or VOM handy, you can use the scope or meter 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. 

        If you do not have a computer handy, or you are uncertain if the 
        computer is setup properly, you can "fake" the FP40 into thinking 
        that the RS232 has been enabled by shorting pins 4 and 5 on the 
        25 pin connector, or pins 7 and 8 on the 9 pin connector. This 
        will enable the FP40's RS232 interface and should cause the red 
        led to start flashing.





















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        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 a 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 RS232 cable) to use the 9-pin port.
        the leds on it.


        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. 









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        Your RS232 diskette contains a program called FCHECK.EXE which
        checks 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.

        In order to run FCHECK with MSDOS or Win3.1, 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 and WinNT), you should run FCHECK32. FCHECK32 does 
        not need 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.  The Help window describes error 
        conditions that might be causing the problem.  

        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 
        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. 
          
        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. 
              
        <eof> 

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