 .MODEL SMALL
.STACK 100H
.DATA
MAIN_MENU DB ,0DH,0AH,"Calculator",0DH,0AH
DB "Press 'A' For ADDITION",0DH,0AH
DB "Press 'S' For SUBTRACTION",0DH,0AH
DB "Press 'M' For MULTIPLICATION",0DH,0AH
DB "Press 'D' For DIVISION",0DH,0AH
DB "Press 'E' For EXIT",0DH,0AH
DB "Press 'R' For RETURN to Main Menu",0DH,0AH
DB "***************************",0DH,0AH
DB "***************************",0DH,0AH
DB "Enter Your CHOICE",0DH,0AH,'$'
NUM1 DB "Enter First Number",0DH,0AH,'$'
NUM2 DB ,0DH,0AH,"Enter SecondNumber",0DH,0AH,'$'
ADD1 DB ,0DH,0AH,"FOR ADDITION",0DH,0AH,'$'
SUB1 DB ,0DH,0AH,"FOR SUBTRACTION",0DH,0AH,'$'
MUL1 DB ,0DH,0AH,"FOR MULTIPLICATION",0DH,0AH,'$'
DIV1 DB ,0DH,0AH,"FOR DIVISION",0DH,0AH,'$'
EX DB ,0DH,0AH,"GOOD BYE AND HAVE A NICE TIME:)",0DH,0AH,'$'
ANS DB ,0DH,0AH,"ANSWER",0DH,0AH,'$'
CONTINUE DB ,0DH,0AH,"DO YOU WANT TO CONTINUE",0DH,0AH,'$'
OP1 DB ?
OP2 DB ?
Operand DB ?
CON DB ?  

.CODE  
.STARTUP
  START:
        MOV AH,09H
        MOV DX, OFFSET MAIN_MENU
        INT 21H
        MOV AH,01H
        INT 21H
        MOV Operand,AL
        MOV AL,Operand
        CMP AL,'A'
        JE ADD
        CMP AL,'S'
        JE SUB
        CMP AL,'M'
        JE MUL
        CMP AL,'D'
        JE DIV
        CMP AL,'R'
        JE START
        CMP AL,'E'
        JE EXIT 
        
ADD: ; PERFORMING ADDITION
MOV AH,09H
MOV DX,OFFSET ADD1
INT 21H
;FIRST OPERAND
MOV AH,09H
MOV DX,OFFSET NUM1
INT 21H
MOV AH,01H  
INT 21H
MOV OP1,AL
;SECOND OPERAND
MOV AH,09H
MOV DX,OFFSET NUM2
INT 21H
MOV AH,01H
INT 21H
MOV OP2,AL
MOV AH,09H
MOV DX, OFFSET ANS
INT 21H
MOV AL,OP1
MOV BL,OP2
ADD AL,BL
AAS
OR AX, 3030H
; PRINT RESULT
MOV AH,0EH
INT 10H
;FOR CONTINUE
MOV AH,09H
MOV DX,OFFSET CONTINUE
INT 21H
MOV AH,01H
INT 21H
MOV CON,AL
MOV AL,CON
CMP AL,'Y'
JE START
CMP AL,'N'
JE EXIT

SUB: ; PERFORMING SUBTRACTION
MOV AH,09H
MOV DX,OFFSET SUB1
INT 21H
;FIRST OPERAND
MOV AH,09H
MOV DX,OFFSET NUM1
INT 21H
MOV AH,01H
INT 21H
MOV OP1,AL
;SECOND OPERAND
MOV AH,09H
MOV DX,OFFSET NUM2
INT 21H
MOV AH,01H
INT 21H
MOV OP2,AL
MOV AH,09H
MOV DX, OFFSET ANS
INT 21H
MOV AL,OP1
MOV BL,OP2
SUB AL,BL
AAS
OR AX, 3030H
; PRINT RESULT
MOV AH,0EH
INT 10H
;FOR CONTINUE
MOV AH,09H
MOV DX,OFFSET CONTINUE
INT 21H
MOV AH,01H
INT 21H
MOV CON,AL
MOV AL,CON
CMP AL,'Y'
JE START
CMP AL,'N'
JE EXIT

MUL: ; PERFORMING MULTIPLICATION
MOV AH,09H
MOV DX,OFFSET MUL1
INT 21H
;FIRST OPERAND
MOV AH,09H
MOV DX,OFFSET NUM1
INT 21H
MOV AH,01H
INT 21H
SUB AL,30H
MOV OP1,AL
;SECOND OPERAND
MOV AH,09H
MOV DX,OFFSET NUM2
INT 21H
MOV AH,01H
INT 21H
SUB AL,30H
MOV OP2,AL
MOV AH,09H
MOV DX, OFFSET ANS
INT 21H
MOV AL,OP1
MOV BL,OP2
MUL BL
ADD AL,30H
; PRINT RESULT
MOV AH,0EH
INT 10H
;FOR CONTINUE
MOV AH,09H
MOV DX,OFFSET CONTINUE
INT 21H
MOV AH,01H
INT 21H
MOV CON,AL
MOV AL,CON
CMP AL,'Y'
JE START
CMP AL,'N'
JE EXIT 

DIV: ; PERFORMING DIVISION
MOV AH,09H
MOV DX,OFFSET DIV1
INT 21H
;FIRST OPERAND
MOV AH,09H
MOV DX,OFFSET NUM1
INT 21H
MOV AH,01H
INT 21H
SUB AL,30H
MOV OP1,AL
;SECOND OPERAND
MOV AH,09H
MOV DX,OFFSET NUM2
INT 21H
MOV AH,01H
INT 21H
SUB AL,30H
MOV OP2,AL
MOV AH,09H
MOV DX, OFFSET ANS
INT 21H
MOV AX,0000H
MOV AL,OP1
MOV BL,OP2
DIV BL
ADD AL,30H
; PRINT RESULT
MOV AH,0EH
INT 10H
;FOR CONTINUE
MOV AH,09H
MOV DX,OFFSET CONTINUE
INT 21H
MOV AH,01H
INT 21H
MOV CON,AL
MOV AL,CON
CMP AL,'Y'
JE START
CMP AL,'N'
JE EXIT

EXIT: ; SAY GOOD BYE AND THEN EXIT
MOV AH,09H
MOV DX,OFFSET EX
INT 21H
.EXIT
END

created 3 years ago

Assembly Online Compiler

Write, Run & Share Assembly code online using OneCompiler's Assembly online compiler for free. It's one of the robust, feature-rich online compilers for Assembly language. Getting started with the OneCompiler's Assembly compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as Assembly and start coding.

About Assembly

Assembly language(asm) is a low-level programming language, where the language instructions will be more similar to machine code instructions.

Every assembler may have it's own assembly language designed for a specific computers or an operating system.

Assembly language requires less execution time and memory. It is more helful for direct hardware manipulation, real-time critical applications. It is used in device drivers, low-level embedded systems etc.

Syntax help

Assembly language usually consists of three sections,

Data section

To initialize variables and constants, buffer size these values doesn't change at runtime.
bss section

To declare variables
text section

_start specifies the starting of this section where the actually code is written.

Variables

There are various define directives to allocate space for variables for both initialized and uninitialized data.

1. To allocate storage space to Initialized data

Syntax

variable-name    define-directive    initial-value

Define Directive	Description	Allocated Space
DB	Define Byte	1 byte
DW	Define Word	2 bytes
DD	Define Doubleword	4 bytes
DQ	Define Quadword	8 bytes
DT	Define Ten Bytes	10 bytes

2. To allocate storage space to un-initialized data

Define Directive	Description
RESB	Reserve a Byte
RESW	Reserve a Word
RESD	Reserve a Doubleword
RESQ	Reserve a Quadword
REST	Reserve a Ten Bytes

Constants

Constants can be defined using

1. equ

To define numeric constants

CONSTANT_NAME EQU regular-exp or value

2. %assign

To define numeric constants.

%assign constant_name value

3. %define

To define numeric or string constants.

%define constant_name value

Loops

Loops are used to iterate a set of statements for a specific number of times.

mov ECX,n
L1:
;<loop body>
loop L1

where n specifies the no of times loops should iterate.

Procedures

Procedure is a sub-routine which contains set of statements. Usually procedures are written when multiple calls are required to same set of statements which increases re-usuability and modularity.

procedure_name:
   ;procedure body
   ret