Indexed Addressing • Effective address is computed as (Index * scale factor) + signed displacement ∗ 16-bit addresses: – displacement: 8- or 16-bit number – scale factor: none (i.e., 1) ∗ 32-bit addresses: – displacement: 8- or 32-bit number – scale factor: 2, 4, or 8 • Useful to access elements of an array (particularly if the element size is 2, 4, or 8 bytes) » Displacement ==> points to the beginning of the array » Index register ==> selects an element of the array (array index) » Scaling factor ==> size of the array element