Emu8086 is a user-friendly microprocessor simulator designed for learning and practicing assembly language programming, allowing users to write, compile, and run 8086 assembly code. Assembly language is a low-level language that uses mnemonics instead of binary code, with 8 general-purpose 16-bit registers available in the 8086 CPU. The document also outlines the process for downloading and installing emu8086 and provides examples of how to use the CPU registers and basic assembly instructions.

1. Introduction to
emu8086
emu8086 is a powerful and user-friendly microprocessor simulator that
allows you to learn and practice assembly language programming. It
provides a comprehensive environment for writing, compiling, and running
8086 assembly code.

2. What is Assembly language
• Assembly Language is a low level programming language
• It is one step higher than machine language.
• In Assembly language symbols are used instead of binary code.
• These symbols are called mnemonics.
• For example ADD instruction is used to Addition two number
• It is also known as Symbolic language.

3. How to download and install emu8086
Step 1
Step 2

4. Step 3
Step 4

5. REGISTORS
It is a memory device use to store data.
These registers are present inside the CPU
GENENRAL PURPOSE REGISTORS:
In 8086 CPU has 8 general purpose registers each registers has its own name:
1. AX
2. BX
3. CX
4. DX
5. SI
6. DI
7. BP
8. SP
9. DS
10.ES
11.SS
12.CS

6. AX- The accumulator register (Divide into AH / AL)
BX-The base address register (Divide into AH / AL)
CX-The count register (Divide into AH / AL)
DX- The data register (Divide into AH / AL)
SI-source index register
DI-Destination Index register
BP-Base pointer
SP-Stack pointer
CS-Point at the segment counting the current program.
DS-Generally points at segment where variables are
defined
ES- Extra segment register, its up to a coder to defines
its usage.
SS- Point at the segment counting the stack.

7. Registers
All general purpose registers are 16bit registers and divided into two parts.
First four registers are AX, BX, CX, DX.
They are two separate 8 bit registers.
Exp: AX is represented as
• AX=AH+AL.
• BX= BH+BL .
• CX= CH+CL.
• DX= DH+DL.

8. Registers are 16 bit separated as (8bit+8bit)
AX=AH+AL
Exp: AX = 00110000 00111001
Then AH= 00110000
And AL= 00111001
16bit 8bit

9. Updated Registers
These Registers are updated from AX, to EAX,RAX from 8
bit to 64 bit, AX reg: is 16 bit, EAX reg: is 32 bit and RAX
reg: is 64 bit.

10. Program
mov Ax,10 Move 10 to ax
mov bx,6 Move 6 to bx
Add ax,bx Add bx to ax
mov bx,34 Move 34 to bx
Sub bx,ax Sub ax to bx
Explanation