Function 6502h          Get Uppercase Table                          DOS 3.3+

    Returns the address of the uppercase table for the specified code
    page and country code. The table maps extended ASCII characters
    (ASCII value > 128) to their uppercase equivalents.

        Entry   AX    = 6502h
                BX    = Code page ID (0FFFFh = current code page)
                CX    = Size of buffer (min. 5)
                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

    ──────────────────────────────────────────────────────────────────

    Format of country info buffer:
        Offset  Size    Description
        00h     1       Info-ID (= 02h)
        01h     4       32-bit address of uppercase table

    The uppercase table starts with a 16-bit value that specifies the
    length of the table; the remainder of the table specifies the
    uppercase equivalents of the ASCII characters from 80h to 0FFh.