indirect address


indirect address

[‚in·də′rekt ə′dres] (computer science) An address in a computer instruction that indicates a location where the address of the referenced operand is to be found. Also known as multilevel address.

indirect address

(processor)An addressing mode found in many processors'instruction sets where the instruction contains the addressof a memory location which contains the address of the operand(the "effective address") or specifies a register whichcontains the effective address. In the first case(indirection via memory), accessing the operand requires twomemory accesses - one to fetch the effective address andanother to read or write the actual operand. Registerindirect addressing requires only one memory access.

An indirect address may be indicated in assembly language byan operand in parentheses, e.g. in Motorola 68000 assembly

MOV D0,(A0)

writes the contents of register D0 to the location pointed toby the address in register A0.

Indirect addressing is often combined with pre- or post-increment or decrement addressing, allowing the address of theoperand to be increased or decreased by one (or some specifiednumber) either before or after using it.

indirect address

An address mode that points to another pointer rather than the actual data. This mode is prohibited in RISC architecture. See indirection and address mode.