8086 Microprocessor Basic Programs

This repository contains basic assembly language programs for the 8086 microprocessor. These programs cover various fundamental operations and problem-solving techniques useful for learning and understanding 8086 assembly programming.

---

📂 List of Programs

These are the solved problems of the 8086 microprocessor asked in the IOE examination.

S.N.	Problem Statement	File Link
1	Assembly level Program to toggle case in 8086	click_here
2	Assembly level Program to change into uppercase and print each character in newline in clear screen in 8086	click_here
3	Assembly level Program in 8086 to Clear Screen	click_here
4	Assembly level Program in 8086 microprocessor to read a string and count no of uppercase and lowercase	click_here
5	Write an Assembly level Program in 8086 Microprocessor to read a string and display it in the next line with the first letter in uppercase and rest in lowercase for each word	click_here
6	Write an Assembly level Program in 8086 Microprocessor to display the multiplication table of the number given by the user in clear screen	click_here
7	Write an Assembly level Program in 8086 Microprocessor to read string and count the number of words	click_here
8	Write an Assembly level Program in 8086 Microprocessor to find the largest and smallest numbers of an array having 10 numbers. Display the found numbers in the clear screen	click_here
9	Two tables contain 10 16-bit data. WAP in 8086 to generate third table which contains 1FFFh if the corresponding data in 1st table is less than that of 2nd table, else store 0000h	click_here
10	Assembly level Program in 8086 Microprocessor to read a string from user and display vowels and consonants seperately	click_here
11	WAP in 8086 to read word from user and display all the alphabets in alternate case (first alphabet in uppercase, second alphabet in lower case , third alphabet in upper case and so on) in clear screen.	click_here
12	WAP in 8086 to read string from user and display only alphabetic characters from the string in clear screen.	click_here
13	WAP in 8086 which will input the username from the keyboard. If the user is "Tribhuvan University" it will display "valid user" else it will display "invalid user".	click_here
14	WAP in 8086 to input a string, count the word of this string whose length is greater than 5 and display this count in clear screen.	click_here

---

Basic Templetes

This is the basic templete that almost every 8086 microprocessor program must have.

.model small	; Defines the memory model. "small" means code and data fit within 64KB each.
.stack 64	; Allocates a 64-byte stack for the program. 
.data		; Section for declaring variables (if needed).

.code		;code section
    main proc far 
        
        MOV ax, @data
        MOV ds, ax	; Initializes the data segment (only needed if data section exists).

        ;your code here...
     
        mov ax, 4C00h	; DOS interrupt to return control to the OS.
        int 21h    
    main endp
 end

Loop

MOV CX, 0
MOV CL, 05h  ;no of times loop runs 
L1:
 
     ;code here...
     INC SI  ;only if SI is used in loop(used in most cases)

LOOP L1
            

New Line

MOV AH, 02H        ; SELECT DOS FUNCTION 02H (DISPLAY CHARACTER)
MOV DL, 0AH        ; ASCII CODE FOR LINE FEED.
INT 21H            ; CALL DOS INTERRUPT TO PRINT THE CHARACTER

MOV DL, 0DH        ; ASCII CODE FOR CARRIAGE RETURN (CR - MOVE TO BEGINNING OF LINE)
INT 21H            ; CALL DOS INTERRUPT TO PRINT THE CHARACTER    

String

.DATA  
    MAXLEN DB 255         ; MAXIMUM BUFFER SIZE (255 CHARACTERS)  
    ACTLEN DB ?           ; ACTUAL LENGTH OF INPUT (FILLED AFTER INPUT)  
    INPUT DB 255 DUP('$') ; BUFFER TO STORE USER INPUT

    MSG DB 'ENTER A STRING: $' ; PROMPT MESSAGE
.CODE  
    MAIN PROC FAR  
        ; INITIALIZE DATA SEGMENT  
        MOV AX, @DATA  
        MOV DS, AX  

        ; DISPLAY MESSAGE "ENTER A STRING: "  
        LEA DX, MSG          ; Store address of MSG in DX
        MOV AH, 09H          ; DOS FUNCTION 09H (PRINT STRING)  
        INT 21H  

        ; READ STRING FROM USER  
        LEA DX, MAXLEN        ; SET BUFFER LOCATION  
        MOV AH, 0AH           ; DOS FUNCTION 0AH (BUFFERED INPUT)  
        INT 21H

         ; DISPLAY ENTERED STRING  
        LEA DX, INPUT         ; SKIP FIRST TWO BYTES (MAXLEN & ACTLEN)  
        MOV AH, 09H           ; DOS FUNCTION 09H (PRINT STRING)  
        INT 21H  

Clear Screeen

.code
    main proc far 
        
        ;clear screen
        MOV AX,0600H;REQ TO SCROLL
    	MOV BH,61H        ;BLUE ON BROWN FOR ATTRIBUT ON PIXEL 
    	MOV CX,0000H
    	MOV DX,1950H
    	INT 10h
    	;Cursor Reset
    	MOV AH, 02h      ; Function 02h: Set cursor position
    	MOV BH, 00h      ; Video page 0
    	MOV DX, 0000h    ; Row 0, column 0
        INT 10h

     main endp
 end

Index

• Other than SI, BX and DI can also be used as index.

---

🛠️ Contributions

Contributions are welcome! If you want to add new programs or improve existing ones, feel free to submit a pull request.

---

Happy Coding!🔥