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The pages on this site contain documentation for very old MS-DOS software, purely for historical purposes. If you're looking for up-to-date documentation, particularly for programming, you should not rely on the information found here, as it will be woefully out of date.

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     Use this chart to determine how many clock cycles are needed for
     effective address calculation time (EA) on the 8086/8088 processors
     and 8087 coprocessor:
 
     Components              EA Clocks     Examples
 
     Displacement            6             mov   ax, stuff
                                           mov   ax, stuff+2
 
     Base or index           5             mov   ax, [bx]
                                           mov   ax, [di]
 
     Displacement plus       6             mov   ax, [bp+8]
     base or index                         mov   ax, stuff[di]
 
     BP+DI or BX+SI          7             mov   ax, [bx+si]
                                           mov   ax, [bx+di]
 
     BP+SI or BX+DI          8             mov   ax, [bx+di]
                                           mov   ax, [bp+si]
 
     BP+DI+disp              11            mov   ax, stuff[bx+si]
     or BX+SI+disp                         mov   ax, [bp+di+8]
 
     BP+SI+disp              12            mov   ax, stuff[bx+di]
     or BX+DI+disp                         mov   ax, [bx+di+20]
 
     Segment override        EA+2          mov   ax, es:stuff
                                           mov   ax, ds:[bp+10]
                                    -♦-