Each
instruction requires certain data in which it has to operate. There are various
technique to specify data for instruction. These technique are called
addressing mode.
1.
Direct
Address Mode: In this
mode of addressing, the address of the operand is given in the instruction
itself. E.g. STA 2000H, IN 02H.
2.
Immediate
Addressing Mode: In this
addressing mode, the operand is specified within the instruction itself. E.g.
MVI A, 20H and LXI H, 2500H.
3.
Register
Addressing Mode: The
operands are in general purpose register. The op-code specifies the address of
the registers in addition to the operation to be performed. E.g. MOV A, B and
ADD B.
4.
Register
Indirect Addressing Mode: In this
mode of addressing, the address of operand is specified by the register pair as
a pointer of operand. E.g. LXI M, 2000H and MOV A, M.
5.
Implied
Addressing Mode: These are
certain instruction which operate on the content of an accumulator, such
instruction do not require the address of operand. E.g. CMA, RAR, HLT etc.
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