Subtract Two Consecutive Bytes of an Array in 8085

Here we will see how we can subtract two consecutive elements in an array using 8085.

Problem Statement

Write 8085 program to subtract two consecutive elements of an array and store them in the same location. The results will be placed at the same location from where they are taken. The numbers are stored from location 8001. The size of array is stored at 8000.

Discussion

Here we will solve this problem by using one subroutine. That will subtract two consecutive numbers and stored them into correct position. That subroutine will be called multiple times to subtract all consecutive pairs. The task will be followed half of the number of elements. So we are taking the count, then rotate it to the right to make it half. We are rotating through carry. if the carry is already high it may store different result, so we are clearing the carry by using STC and CMC instructions.

Input

Flow Diagram

Program

Output