Addressing Modes

(A)        REGISTER MODE

                 

                     The operand is the contents of a processor register the name (address) of the register is given in the instruction processor register are used as temporally storage locations. Where the data in a register are accessed using the register mode.

(B)       ABSOLUTE MODE

                 

                     The operand is in a memory location the address of this location is given explicitly in the instruction. The absolute mode can represent global variables in program a declaration such as integer A.B; in a high level language program will cause the complier to allocate a memory location to each of the variables A and B.

(C)       IMMEDIATE MODE

                 

                     The operand is given explicitly in the instruction address and data constants can be represented in assembly language using the immediate mode.

For example

         The instruction move 200 immediate, replaces the value 200 in register or clearly the immediate mode is only used to specify the value of a source operand.

                     Using a subscript to denote the immediate mode is not appropriate in assembly languages. A common collection is to use the sharp Sign (#) in front of the value to indicate that this value is to be used as an immediate operand.

(D)       INDIRECT MODE

                 

                     The effective address of the opened is the contents of register or memory location whose address appears in the instruction we denote indirection by pacing the name of the register or the memory address.