8085 Program to find the HCF of two given bytes

In this program we will see how to find the HCF or GCD of two numbers using 8085.

Problem Statement

Write 8085 Assembly language program to find the HCF of two numbers stored at memory location 8000H and 8001H.

Discussion

This problem is solved by the Euclidean algorithm to find HCF. This algorithm is very simple.The algorithm steps are as follows −

  • If first number and second number are same, then

    • go to step 3.

Else if first number < second number, then 


    • exchange no1 andno2.

  • first-number <-first-number – second-number; go to step 1

  • Display result as first-number

The values are stored at location 8000H and 8001H, and the result will be stored at location8050H.

Input

First Input

Address Data
... ...
8000 2D
8001 69
... ...
8050 0F
... ...


Second Input

Address Data
... ...
8000 25
8001 35
... ...
8050 01
... ...

Flow Diagram

Program

Address HEXCodes Labels Mnemonics Comments
F000 21, 00, 80
LXI H,8000H Point to the first number
F003 7E
MOV A, M Load the first number into Acc
F004 23
INX H    Point to next location
F005 46
MOV B, M Load the second number
F006 B8 LOOP CMP B    Compare B with A
F007 CA, 17, F0
JZ STORE     When A and Bare same, store the result
F00A DA, 11, F0
JC EXG    If B > A, then exchange B and A
F00D 90
SUB B    if B < A,subtract B from A
F00E C3, 06, F0
JMP LOOP   Jump to LOOP
F011 48 EXG MOV C,B Load C with B
F012 47
MOV B, A Move A to B
F013 79
MOV A, C Move C to A
F014 C3, 06, F0
JMP LOOP     Jump to LOOP 
F017 32, 50, 80 STORE STA 8050H    Store the value into memory
F01A 76
HLT Terminate the program


Output

First Output

Address Data
... ...
8050 0F
... ...


Second Output

Address Data
... ...
8050 01
... ...
Updated on: 2019-07-30T22:30:24+05:30

3K+ Views

Kickstart Your Career

Get certified by completing the course

Get Started
Advertisements