Immediate Addressing Mode. In this addressing mode the operand is a constant value whose binary encoded form is stored in the instruction itself. Thus this value is present in the instruction register or effective address register after the instruction has been fetched. Rather than attempting to memorize a table like this for each instruction learn the following two general principles about addressing. The immediate mode cannot be used for the destination operand.
Immediate mode creates a constant value encoded in one of the operand fields of the instruction.
It does not make sense for this to be the place where a result is stored. In binary operations both operands cannot be memory references. The two data paths to the ALU come from the bank of data registers and a temporary register. One memory operand can be placed in the temporary register but the other must come from the bank of registers or be an immediate operand. It retrieves one value from one location and stores it in another.