MPLab1 Addition

32-bit Binary Addition Step by Step

1. Specify the memory model for code, data, and stack segments

.model small 
.stack 100H 

2. Define your data in the data section ( here you can define various data items: variables, constants, strings, arrays)

.data                           ; .data directive indicates the beginning of data section 
data1 dd 00H 
num1 db 10,13,"Enter the first number: $" 
num2 db 10,13,"Enter the second number: $" 
sum db 10,13,"The sum is :$" 

3. Define your instruction in the code section (here you write the assembly instructions that perform computations, control program flow, and interact with data variables and memory)

.code                           ; .code directive indicates the beginning of code section 
.startup                        ;  the entry point of the program

MOV EBX, 00000000

The function of Lex is as follows:

• Firstly lexical analyzer creates a program lex.l in the Lex language. Then Lex compiler runs the lex.l program and produces a C program lex.yy.c.
• Finally C compiler runs the lex.yy.c program and produces an object program a.out.
• a.out is lexical analyzer that transforms an input stream into a sequence of tokens.
  
  

The Assembly Program Structure

An assembly program is separated into three sections as follows:

.MODEL SMALL
.STACK 100h

.DATA
;data definition go here

.CODE
;instructions go here