

                  Changes or Special Notes About 6400 Commands
                                                                 02/21/94


        The RS232 based FIPP (Frye Instrument Packet Protocol) was first 
        implemented on the Fonix 6500 Real Time Hearing Aid Analyzer. 
        Other Frye instruments such as the Fonix 6400 use the same 
        command set (or a sub-set of the commands).  The full list of 
        RS232 commands used by Frye instruments that use the FIPP 
        interface are listed in the RS232 Command Reference Guide.
        Over time there have been some minor changes and additions. These 
        changes and/or additions are described below.


        Curve data:

        Prior to version 1.10 the 6400 had 9 curve buffers available for 
        use. With version 1.10 four additional buffers are provided 
        bringing the total curve buffers available to 13.

        There are four base curves and five or nine additional reference 
        curves used in multi-curve. The curves are referenced in Get 
        CurveFrame or Set CurveFrame by the Curve Frame number. 

             6400 Curve               Reference Number

             Curve 1                  0  (Unaided response)
             Curve 2                  1  (Aided response)
             Curve 3                  2  (Insertion gain)
             Curve 4                  3  (Target insertion)

             Reference 1              4  (multicurve registers)
             Reference 2              5
             Reference 3              6
             Reference 4              7
             Reference 5              8
             Reference 6              9  (new with V1.10)
             Reference 7             10  (new with V1.10)
             Reference 8             11  (new with V1.10)
             Reference 9             12  (new with V1.10)

        The curve numbers refer to the curve stack.  
        Curve numbers 0 through 3 correspond to curves 1 through 4. 
        Curve numbers 4 through 12 correspond to multi-curve reference 
        curves 1 through 9.

        The 6400 uses curve frame type '1'. Refer to the Curve Frame 
        Reference Guide for a description of the curve frame types and 
        how they are used.







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        New commands:

        In version 1.10 several new probe commands have been added. these 
        include Get/Set Noise Reduction, Get/Set Automatic Status, 
        Get/Set Output Limit Value, Get/Set RefMic Status, Get/Set 
        Frequency, Get/Set Source Amplitude, Do Sweep, Get/Set Active 
        Status, and Get Microphone Input Value. The commands in version 
        1.10 of the 6400 are based on the command set of version 2.50 of 
        the 6500 probe mode.


        Machine type:

        The 6400 always returns a machine type of 0001. 


        Machine sub-type:

        The 6400 does not return a machine sub-type field (the returned 
        version packet is one field shorter).


        Multi-Curve:

        In version 1.05 of the 6400, the Multi-Curve mode now allows 
        commands to operate as indicated in the list. In version 1.04 the 
        Multi-curve mode did not allow RS232 operation.


        Get RefMic Data:

        This only works in probe mode, while in pure tone, and only when 
        a test is not active.


        Set/Get KeyCode:   

        The 6400 key structure is similar to the 6500. On the 6400, when 
        a key is pressed, that code will be returned only once when 
        requested. A follow on call will read a zero if no other key has 
        been pressed. See the 6500 notes for additional information.


        A note about curves:

        When a 6400 curve frame is requested which does not contain valid 
        data the 6400 returns a NAK, this can be confusing as this is the 
        same error returned when an invalid curve number (i.e. 99) is 
        requested.







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                          6400 Option Flags Description

        The 6400 contains a standard option flag indicator and a custom 
        option flag indicator that can be read by requesting the version 
        number from the 6400. The software version request will return 
        the Software version installed in the 6400 followed by the option 
        flags. The machine type defines the machine being used.

        The information is provided as an array of 16 bit words in the 
        following form:

                  vvvv - Version number
                  oooo - Standard option low word
                  oooo - Standard option high word
                  cccc - Custom option low word
                  cccc - Custom option high word
                  0001 - Machine type

        The version number is the indicated version times 100. Thus 
        version 2.24 would be given as "224". The version number is given 
        as a binary number. The current version and date is visually 
        presented on the 6400's monitor when you first turn it on (the 
        logo screen).

        Following the version number is the standard option flag 
        indicator. The standard option flag indicator consists of a 32 
        bit long word which is used to indicate when a standard option 
        has been installed on the 6400. When the bit is on (1), the 
        option has been installed in the 6400 when the bit is off (0) the 
        option is not installed.

        Following the standard option flag indicator is the custom option 
        flag indicator. The custom option flag indicator also consists of 
        a 32 bit long word which is used to indicate when a custom option 
        has been installed on the 6400. When the bit is off (0), the 
        option has been installed in the 6400 when the bit is on (1) the 
        option is not installed (opposite of standard options).

        Following the custom option flag indicator is the machine 
        identification word. The machine identification word indicates 
        which Frye instrument is responding to the commands. The 6400 
        instrument will always return a 0001 in the machine type word.

        Standard options are those options which are available on all 
        6400s. A custom option is an option which is provided through a 
        special arrangement with a customer and is not available on other 
        6400s.

        Since custom option definitions can change over time, the 
        individual flag definitions are not covered by this appendix. If 
        you require specific information on a custom option you should 
        contact Frye Electronics for more information.




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        Option flag:

        The option flag consists of a 32 bit long word which is used to 
        indicate when a standard option has been installed on the 6400. 
        When the bit is on (1), the option has been installed in the 6400 
        when the bit is off the option is not installed.

        Below is a table showing the option flag bits and the positions 
        and meanings of the bits:

        bit number    flag      functional                bit position  
        (long) word - label   - description             76543210 76543210
        -----------------------------------------------------------------
        ( 0)   0    - ENOP00  - <reserved>              ........ .......x
        ( 1)   1    - ENOP01  - <reserved>              ........ ......x. 
        ( 2)   2    - ENOP02  - <reserved>              ........ .....x..
        ( 3)   3    - ENOP03  - <reserved>              ........ ....x... 
        ( 4)   4    - ENOP04  - <reserved>              ........ ...x....
        ( 5)   5    - ENOP05  - <reserved>              ........ ..x..... 
        ( 6)   6    - ENOP06  - <reserved>              ........ .x......
        ( 7)   7    - ENOP07  - <reserved>              ........ x....... 
        ( 8)   8    - ENOP08  - <reserved>              .......x ........
        ( 9)   9    - ENOP09  - <reserved>              ......x. ........ 
        (10)  10    - ENOP10  - <reserved>              .....x.. ........
        (11)  11    - ENOP11  - <reserved>              ....x... ........ 
        (12)  12    - ENOP12  - <reserved>              ...x.... ........
        (13)  13    - ENOP13  - <reserved>              ..x..... ........ 
        (14)  14    - ENOP14  - <reserved>              .x...... ........
        (15)  15    - ENRS232 - RS232                   x....... ........ 

        (16)   0    - ENOP16  - <reserved>              ........ .......x
        (17)   1    - ENOP17  - <reserved>              ........ ......x. 
        (18)   2    - ENOP16  - <reserved>              ........ .....x..
        (19)   3    - ENOP17  - <reserved>              ........ ....x... 
        (20)   4    - ENOP16  - <reserved>              ........ ...x....
        (21)   5    - ENOP17  - <reserved>              ........ ..x..... 
        (22)   6    - ENOP16  - <reserved>              ........ .x......
        (23)   7    - ENOP17  - <reserved>              ........ x....... 
        (24)   8    - ENOP16  - <reserved>              .......x ........
        (25)   9    - ENOP17  - <reserved>              ......x. ........ 
        (26)  10    - ENOP16  - <reserved>              .....x.. ........
        (27)  11    - ENOP17  - <reserved>              ....x... ........ 
        (28)  12    - ENOP16  - <reserved>              ...x.... ........
        (29)  13    - ENOP17  - <reserved>              ..x..... ........ 
        (30)  14    - ENOP16  - <reserved>              .x...... ........
        (31)  15    - ENOP17  - <reserved>              x....... ........ 


        Flag bits marked <reserved> are reserved for future use. 
        These flags will change in the future and should not be relied 
        upon to remain in a particular condition. Contact Frye 
        Electronics for an option list update if you are working with an 
        option not listed.



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