LAHF             Load Register AH from Flags         Flags: not altered

          Logic:     AH bits    .    Flag-reg bits
                    7 6 4 2 0   .      S Z A P C

    LAHF copies the five 8080/8085 flags (Sign, Zero, Auxiliary Carry,
    Parity, and Carry) into bits 7, 6, 4, 2, and 0, respectively, of the
    AH register. The flags themselves are unchanged by this instruction.

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   Operands                  Clocks   Transfers  Bytes   Example
   no operands                 4          -        1     LAHF
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       Notes:         This instruction is primarily used to provide upward
                      compatibility between the 8080/8085 family and the
                      8086 family.

                      After this instruction is executed, bits 1, 3 and 5
                      of AH are undefined.