Addition Subtraction

EXPT NO: DATE:

ADDITION & SUBTRACTION

AIM To write assembly language program for performing addition and subtraction operation of two byte numbers.

APPARATUS REQUIRED: SL.NO ITEM SPECIFICATION QUANTITY

1. Microprocessor kit 8086 kit 1 2. Power Supply +5 V dc 1 3. Keyboard 1

ALGORITHM: (i ) 16 - b i t a dd i t i o n h) Initialize the MSBs of sum to 0 i) Get the first number. j) Add the second number to the first number. k) If there is any carry, increment MSBs of sum by 1. l) Store LSBs of sum. m) Store MSBs of sum. (ii ) 16 - b i t s ub t r a ctio n f) Initialize the MSBs of difference to 0 g) Get the first number h) Subtract the second number from the first number. i) If there is any borrow, increment MSBs of difference by 1. j) Store LSBs of difference k) Store MSBs of difference. (i) Mu lti p lic a ti o n o f 16 - b i t n umb ers : a) Get the multiplier. b) Get the multiplicand c) Initialize the product to 0. d) Product = product + multiplicand e) Decrement the multiplier by 1 f) If multiplicand is not equal to 0, repeat from step (d) otherwise store the product. (ii) D i v i s io n o f 1 6 - b i t n u m b e r s . a) Get the dividend b) Get the divisor c) Initialize the quotient to 0. d) Dividend = dividend – divisor e) If the divisor is greater, store the quotient. Go to step g. f) If dividend is greater, quotient = quotient + 1. Repeat from step (d) g) Store the dividend value as remainder. FLOWCHART ADDITION SUBTRACTION

START START

SET UP COUNTER (CY) SET UP COUNTER (CARRY)

GET FIRST OPERAND GET FIRST OPERAND TO A

GET SECOND OPERAND SUBTRACT TO A SECOND OPERAND FROM MEMORY

YES A = A + B IS THERE ANY CY YES NO IS THERE COUNTER = ANY CARRY COUNTER + 1 COUNTER = COUNTER + 1 STORE THE DIFFERENCE NO

STORE THE SUM STORE THE CARRY

STORE THE CARRY STOP

STOP MULTIPLICATION DIVISION

Start Start

Load Divisor & Dividend Get Multiplier & Multiplicand

REGISTER=00 QUOTIENT = 0

DIVIDEND = DIVIDEND - DIVISOR REGISTER = REGISTER + MULTIPLICAND

QUOTIENT = QUOTIENT + 1 Multiplier=MULTIPLIER – 1

IS IS NO NO MULTIPLIER DIVIDEND < =0? DIVISIOR?

YES STORE THE RESULT YES

STORE QUOTIENT STORE REMAINDER = DIVIDEND NOW STOP STOP ADDITION PROGRAM COMMENTS

MOV CX, 0000H Reset counter CX

MOV AX,[1200] Get the first data in AX reg

MOV BX, [1202] Get the second data in BX reg

ADD AX,BX Add the contents of both the regs AX & BX and store the result in AX JNC L1 Check for carry

INC CX If carry exists, increment the CX by 1

L1 MOV [1206],CX Store the carry in CX

MOV [1204], AX Store the sum in AX

INT 3 Stop the program

SUBTRACTION PROGRAM COMMENTS

MOV CX, 0000H Reset counter CX

MOV AX,[1200] Get the first data in AX reg

MOV BX, [1202] Get the second data in BX reg

SUB AX,BX Subtract the contents of BX from AX and store the result in AX JNC L1 Check for borrow

INC CX If borrow exists, increment the CX

L1 MOV [1206],CX Store the borrow

MOV [1204], AX Store the difference

INT 3 Stop the program MULTIPLICATION

PROGRAM COMMENTS

MOV AX,[1200] Get the first data

MOV BX, [1202] Get the second data

MUL BX Multiply both

MOV [1206],AX Store the lower order product

MOV [1208],DX Store the higher order product

INT 3 Stop the program

DIVISION

PROGRAM COMMENTS

MOV AX,[1200] Get the first data (Dividend)

MOV DX, [1202] Initialize DX register with 0000h

MOV BX, [1204] Get the second data(Divisor)

DIV BX Divide the dividend by divisor

MOV [1206],AX Store the Quotient

MOV [1208],DX Store the remainder

INT 3 Stop the program OUTPUT:

ADDITION- With carry/without carry

input output

MEMORY

SUBTRACTION-with borrow/without borrow

MEMORY

MULTIPLICATION

MEMORY

DIVISON

MEMORY

RESULT: