Addition of two packed BCD numbers entered through keyboard

• Write an 8086 program that adds two packed BCD numbers input from the keyboard and computes and displays the result on the system video monitor
• Data should be in the form 64+89= The answer 153 should appear in the next line.

Program: 

Mov dx, buffer address

Mov ah,0a

Mov si,dx

Mov byte ptr [si], 8

Int 21

Mov ah,0eh

Mov al,0ah

Int 10 ;                               BIOS service 0e line feed position cursor

sub byte ptr[si+2], 30h

sub byte ptr[si+3], 30h

sub byte ptr[si+5], 30h

sub byte ptr[si+6], 30h

Mov cl,4

Rol byte ptr [si+3],cl

Rol byte ptr [si+6],cl

Ror word ptr [si+2], cl

Ror word ptr [si+2], cl

Mov al, [si+3]

Add al, [si+6]

Daa

Mov bh,al

Jnc display

Mov al,1

Call display

Mov al,bh

Call display

Int 20

Display Subroutine:

mov bl,al ;         Save original number and al,f0 ;Force bits 0-3 low

mov cl,4 ;           Four rotates

ror al,cl ;             Rotate MSD into LSD

add al,30 ;          Convert to ASCII

mov ah,0e ;       BIOS video service 0E

int 10 ;                Display character

mov al,bl ;          Recover original number

and al,0f ;           Force bits 4-7 low

add al,30 ;          Convert to ASCII

int 10 ;                 Display character

ret ;                      Return to calling program

                                                   ;

                                                             ;Input buffer begins here

interfacing 7 segment display with 8086 processor

Statement: Program to interface 8086 microprocessor kit with Seven Segment Display and make any digit to Blink

Description:

In this program we interface 8086 microprocessor with Seven Segment Display and diaplay a digit.  To interface with Seven Segment Display,we must be familiar with 8255A PPI, which has three ports which can be used as I/O ports. The ports A, B and C are identified using addresses 19H, 1BH, and 1DH respectively and control register address is 1FH. We use Seven Segment Display structure using the following digit

	Digit	Hexadecimal	Decimal	Binary
8	0 1 2 3 4 5 6 7 8 9	C0 F9 A4 B0 99 92 82 F8 80 90	192 249 164 176 153 146 130 248 128 144	11000000 11111001 10100100 10110000 10011001 10010010 10000010 11111000 10000000 10010000

code: 

Source program:

 MOV AL,10000000B

 OUT PPI_C, AL

STR:   MOV AL, 10011001B

 OUT PPIA,AL

 MOV CX, FFFFH

DEL:    NOP

 NOP

 NOP

 LOOP DEL

 MOV AL, 11111111B

 OUT PPIA, AL

 MOV CX, FFFFH

DEL1:    NOP

 NOP

 NOP

 LOOP DEL1

 JMP  STR

 HLT

Traffic light programming in assembly for 8086

; Traffic ligts test 2 for
; c:\emu8086\devices\Traffic_Lights.exe

; This is just an example of how to set the lights,
; DO NOT RUN AT MAXIMUM SPEED, DO NOT USE REAL CARS.
;)


#start=Traffic_Lights.exe#

name "traffic2"

yellow_and_green equ      0000_0110b
red              equ      0000_0001b
yellow_and_red   equ      0000_0011b
green            equ      0000_0100b

all_red          equ      0010_0100_1001b

start:
nop


; 0,1,2

mov ax, green
out 4, ax

mov ax, yellow_and_green
out 4, ax

mov ax,red
out 4, ax

mov ax, yellow_and_red
out 4, ax


; 3,4,5

mov ax, green << 3
out 4, ax

mov ax, yellow_and_green << 3
out 4, ax

mov ax,red << 3
out 4, ax

mov ax, yellow_and_red << 3
out 4, ax



; 6,7,8

mov ax, green << 6
out 4, ax

mov ax, yellow_and_green << 6
out 4, ax

mov ax,red << 6
out 4, ax

mov ax, yellow_and_red << 6
out 4, ax



; 9,A,B

mov ax, green << 9
out 4, ax

mov ax, yellow_and_green << 9
out 4, ax

mov ax,red << 9
out 4, ax

mov ax, yellow_and_red << 9
out 4, ax


; all

mov ax, all_red
out 4, ax

mov ax, all_red << 1  ; all yellow
out 4, ax

mov ax, all_red << 2  ; all green :)
out 4, ax


jmp start