List out features of any four addressing modes of 8051.

1 Answer

Answer :

1.Immediate addressing mode: In this Immediate Addressing Mode, the data is provided in the instruction itself. The data is provided immediately after the opcode. These are some examples of Immediate Addressing Mode.

MOVA, #0AFH;


2. Register addressing mode: In the register addressing mode the source or destination data should be present in a register (R0 to R7). These are some examples of RegisterAddressing Mode.

MOVA, R5;

MOVR0, A;


3. Direct Addressing Mode: In the Direct Addressing Mode, the source or destination address is specified by using 8-bit data in the instruction. Only the internal data memory can be used in this mode. Here some of the examples of direct Addressing Mode.

MOV80H, R6;

MOVR2, 45H;

MOVR0, 05H;


4. Register indirect addressing Mode: In this mode, the source or destination address is given in the register. By using register indirect addressing mode, the internal or external addresses can be accessed. The R0 and R1 are used for 8-bit addresses, and DPTR is used for 16-bit addresses, no other registers can be used for addressing purposes. Let us see some examples of this mode.

MOV 0E5H, @R0

MOV @R1, 80H


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