8088/8086  Effective Address (EA) Calculation

                   Description                            Clock Cycles

        Displacement                                            6
        Base or Index (BX,BP,SI,DI)                             5
        Displacement+(Base or Index)                            9
        Base+Index (BP+DI,BX+SI)                                7
        Base+Index (BP+SI,BX+DI)                                8
        Base+Index+Displacement (BP+DI,BX+SI)                  11
        Base+Index+Displacement (BP+SI+disp,BX+DI+disp)        12


        - add 4 cycles for word operands at odd addresses
        - add 2 cycles for segment override
        - 80188/80186 timings differ from those of the 8088/8086/80286


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