AAD             ASCII Adjust before Division         Flags: O D I T S Z A P C
                                                            ? - - - * * ? * ?
AAD

        Logic   AL ← AH * 10 + AL
                AH ← 0

    AAD converts the unpacked two-digit BCD number in AX into binary
    in preparation for a division using DIV or IDIV, which require
    binary rather than BCD numbers.

    The result produced by the subsequent division will be an unpacked
    BCD number.


    Opcode      Format
    D5 0A       AAD


    Length and timing
    Operands    Bytes   8088    186     286     386     486     Pentium
    -            2      60      15      14      19      14      10   NP