        RS232 Option Installation Instructions for               10/15/92 
        Fonix FA series Audiometers

        1. Check that your upgrade kit contains the following items:

           - 16C450 UART chip
           - One EPROM chip
           - Floppy disk containing sample programs and documentation
           - Internal ribbon cable with 10-pin connectors
           - RS232 BOARD with mount screws
           - External RS232 cable to connect audiometer to computer


        2. Remove the cover from the audiometer

           a. Unplug the audiometer power cord from the wall if currently 
              plugged in.

           b. Unplug any cables attached to the rear panel of the 
              audiometer.

           c. Remove the seven screws securing the top to the audiometer 
              chassis.

           d. Lift the top at the front of the audiometer. It will pivot 
              on two hinges located at the rear of the chassis. Lift all 
              the way until the top rests on its back side. Note that the 
              back part of the chassis will rise slightly as you do this. 


        3. Install the 16C450 UART chip and check jumper on the 
           CPU/KEYBOARD

           a. Install the 16C450 UART chip into the empty 40-pin IC 
              socket that is located near the bottom (rear) right edge of 
              the CPU/KEYBOARD. The index notch on the chip should be 
              pointing toward the center of the CPU board when it is 
              properly installed.
         
              Check to make sure that none of the legs of the IC are bent 
              under or sticking out of the socket. 

           b. If you wish to use the standard FIPP protocol (default), 
              move the jumper (JP1) next to the UART so that it is on the 
              two pins oriented parallel to the UART (1 and 2). If you 
              wish to use the limited ASCII protocol, move the jumper so 
              that it is on the two pins perpendicular to the UART (2 and 
              3). For best operation, you should use the FIPP protocol 
              method of communication.





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        4. Install the RS232 BOARD

           a. Remove the blank cover over the RS232 option hole in the       
              audiometer backpanel by breaking the plastic studs with a       
              pair of pliers. Remove the clips from the studs if they       
              still remain. Discard the cover and clips. 

           b. Using the screws provided, install the RS232 BOARD in the 
              hole in the backpanel. Install the board so that the side 
              of the RS232 board with the components installed is towards 
              the output board and the solder side of the board is 
              towards the power switch. Double check that pin one       
              (printed "1") of the ten pin connector is pointing towards 
              the chassis bottom. 

           c. Attach the supplied ten conductor ribbon cable to the RS232 
              BOARD. Make sure that the color dots on the cable match the 
              color dots on the board and that they are next to each 
              other. Attach the other end of the ribbon cable to the 
              CPU/KEYBOARD board at J5 (next to the UART). Make sure that 
              the color dots on the cable match the color dots on the 
              CPU/KEYBOARD and that they are next to each other. Pin "1" 
              on the RS232 BOARD should match up with the "1" one on the 
              CPU board. On both connectors, the color stripe on the 10 
              pin ribbon cable should be at pin "1".

              It is important that this connector be correctly installed. 
              If it is incorrectly installed, the RS232 option board will 
              be destroyed when you apply power to the audiometer.


        5. Install the EPROM chip in the CPU/KEYBOARD and check jumper

           a. The EPROM chip is located in a socket (U13) along the right 
              edge the CPU/KEYBOARD. Remove the current chip from the 
              socket. Install the new EPROM chip into the socket.  The 
              notch on the EPROM should be oriented toward center of the 
              board when properly installed.  It is important to double 
              check this since installing the EPROM backwards will 
              destroy it if you apply power to the audiometer.  

           b. Check the EPROM style jumper (JP2) that can be found next 
              to the EPROM. The jumper should be connected to pins 1 and 
              2. On older audiometers, the jumper may be connected to 
              pins 2 and 3. If this is the case, move the jumper to pins 
              1 and 2. 


        6. Close the audiometer case and install the seven screws you 
            removed previously. 





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        7. Test the audiometer to see if it still works

           a. Turn on the audiometer.  Diagnostic tests are run 
              automatically on power up.  The LEDs on the front panel 
              should light up. After a few seconds the LEDs should go out 
              (except those indicating normal operating conditions. If 
              the green Hearing Aid Simulator LEDs flash, refer to the 
              operators manual to determine the type of error being 
              indicated. 
              
           b. Attach the External RS232 cable (supplied in the RS232 
              option kit) to the RS232 Computer Interface connector on 
              the back of the audiometer. 

              1. If you selected the standard FIPP option when you 
                 installed the 16C450 UART, the red LED on the cable 
                 should be flashing. If you selected the limited ASCII 
                 option the LED will not flash. The FIPP option is the 
                 standard default selection.

              2. To test the ASCII option, you will need a terminal (or 
                 terminal emulation software on your computer) set to 
                 9600 baud, 8 data bits, one stop bit. On the terminal 
                 (or in the terminal program) press the return key. 
                 You should see a question mark returned (?) followed by 
                 a command prompt on the next line. Enter in the command 
                 VERSION. You should see the copyright, date, version 
                 and model message displayed.

              3. To test the FIPP option, you will need a computer with a 
                 serial port. Attach the External RS232 cable to the 
                 computer's RS232 port and run the FCHECK program 
                 provided on the floppy disk.         

              4. Refer to the Sample programs on the provided floppy disk 
                 for programs that show how you can use the RS232 
                 interface with the audiometer. 

        8. Return the EPROM that was removed from the CPU board to Frye 
           Electronics, Inc. in the mailing box provided.










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