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Effective Address (EA) Calculations

    This table lists the number of clock cycles required to calculate the
    effective address on the 8088 microprocessor.  The 80x86 processors
    require considerably fewer clock cycles to calculate effective
    addresses, so this table represents the worst-case.

    EA Component                  8088 Clocks          Example
    Displacement                       6               MOV AX,ADDR

    Register indirect                  5               MOV AX,[BP]
        BX, BP, SI, DI

    Displacement + Base or Index       9               MOV AX,ADDR[BP]
        BX + Disp, BP + Disp
        SI + Disp, DI + Disp

    Base + Index
        BP + DI, BX + SI               7               MOV AX,[BP+DI]
        BP + SI, BX + DI               8               MOV AX,[BX+DI]

    Displacement + Base + Index
        BP + DI + Disp                 11              MOV AX,ADDR[BP+DI]
        BX + SI + Disp

        BP + SI + Disp                 12              MOV AX,ADDR[BP+SI]
        BX + DI + Disp

       Notes:         Add 2 clocks for segment overrides

                      Each memory reference requires an additional 4 clock
                      cycles.  The Transfers field in the instruction
                      timing charts gives the number of memory references
                      for each instruction.

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