Basic Arithmetic Operation

Explanation

Here is a concise breakdown of the program:

1. Purpose

This program performs a bitwise LOGICAL OR operation between two 8-bit hexadecimal numbers (0Fh and F0h). It demonstrates how to combine bit patterns and store the result in the Accumulator.

2. Key Concepts

• Immediate Data Loading (MVI): Loading a specific value directly into a register.
• Accumulator-Centric Design: In 8085 assembly, ALU operations (like ORA) use Register A (the Accumulator) as one input and store the final result back in Register A.
• Bitwise OR Logic: A bit in the result becomes 1 if at least one corresponding input bit is 1.

3. Code Walkthrough

| Instruction | Action | Binary Representation | | :--- | :--- | :--- | | MVI A, 0Fh | Loads value 0Fh into Accumulator (A) | A = 0000 1111 | | MVI B, 0F0h | Loads value F0h into Register B | B = 1111 0000 | | ORA B | ORs Register B with A; saves result in A | 0000 1111 OR 1111 0000 = 1111 1111 | | HLT | Stops execution | Program stops |

4. Output

• Register A (Accumulator): FFh (Binary: 1111 1111)
• Register B: F0h (Unchanged)