Basic Arithmetic Operation

Explanation

Here is the breakdown of the assembly (8085 ASM) program:

1. Purpose

This program adds two hexadecimal numbers (25h and 15h) together using CPU registers and stops execution. The final sum is stored in the Accumulator.

2. Key Concepts

• Immediate Addressing Mode (MVI): Loading fixed data values directly into registers.
• Accumulator-Based Arithmetic (ADD): Operations automatically use the Accumulator (Register A) as one operand and overwrite it with the result.
• Program Termination (HLT): Halting the CPU to stop further execution.

3. Code Walkthrough

• MVI A, 25h — Loads the value 25h (hexadecimal) into Register A (Accumulator).
• MVI B, 15h — Loads the value 15h (hexadecimal) into Register B.
• ADD B — Adds the contents of Register B (15h) to Register A (25h). The calculated sum is stored back in Register A.
• HLT — Halts (stops) the processor.

4. Output

• Register A (Accumulator): 3Ah (Hexadecimal addition: 25h + 15h = 3Ah, which is 58 in decimal)