8 bit addition in all addressing modes

Aim: 

Write an assembly language program to perform two 8 bit numbers addition using immediate, direct, indirect and register addressing modes.

Apparatus:

A computer loaded with Keil or edsim51.

Program:

Immediate mode:

ORG 0000H

LJMP MAIN

MAIN:

MOV A,#50H

ADD A,#30H

END

Note: Observe 'Acc' for the result.

Direct mode:

ORG 0000H

LJMP MAIN

MAIN:

MOV 40H,#50H

MOV A,#30H

ADD A,40H

END

Note: Observe 'Acc' for the result.

Indirect mode:

ORG 0000H

LJMP MAIN

MAIN:

MOV 40H,#50H

MOV 41H,#30H

MOV R0,#40H

MOV R1,#41H

MOV A,@R0

MOV B,@R1

ADD A,B

END

Note: Observe 40H, 41H locations, R0, R1 registers and A, B for intermediate results.

Observe 'Acc' for the final result.

Register mode:

ORG 0000H

LJMP MAIN

MAIN:

MOV 40H,#50H

MOV 41H,#30H

MOV A,40H

MOV R0,41H

ADD A,R0

END

Note: Observe 40H, 41H locations, R0 register and A for intermediate results.

Observe 'Acc' for the final result.

Result:

Performed 8-bit addition using all addressing modes.

    In the same way, we can program for 8-bit subtraction, multiplication, division using SUB, MUL, DIV instructions.