Function 6501h          Get Extended Country Information             DOS 3.3+

     Returns the country information that DOS uses to control the
     keyboard and screen.

        Entry   AX    = 6501h
                BX    = Code page ID (0FFFFh = current code page)
                CX    = Size of buffer (min. 5, set to 41)
                DX    = Country code (0FFFFh = current country)
                ES:DI = Pointer to country info buffer

        Return  Buffer updated
                or
                AX = Error code, if CF is set
                     | 01h Invalid function (CX < 5)
                     | 02h File not found (bad code page/country code)

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    Format of country info buffer:
        Offset  Size    Description
        00h     1       Info-ID (= 01h)
        01h     40d     ExtCountryInfo structure


    Note
    If the parameter passed in CX is greater than 5 but less than the
    size of the country information, the information is truncated and
    no error is returned.