The first thing that came in to mind when I started learning about electronics is how do computers work? So I did some research and found out that computers do really simple things, just very, very fast. One of them is adding two numbers together, so I decided that I would make a calculator with an Arduino Uno.

The finished product worked very well, capable of adding two numbers nearly instantly.

If wired and coded correctly, this calculator should be able to add two numbers both up to 7 and produce a sum up to 14. Math homework solved!

EXPANDED TECHNICAL DETAILS

Binary Logic Operations

This project demonstrates the fundamentals of digital logic and computer arithmetic using an Arduino Uno as the "Arithmetic Logic Unit" (ALU).

• Inputs: 3 digital pins are used for the first binary number, and another 3 for the second. Pull-up or pull-down resistors ensure stable logic levels.
• Processing: The Arduino performs logical operations (AND, OR, NOT, XOR) and arithmetic additions. For a 3-bit adder, it handles carriers manually or through software-level bitwise operations.

Visualization

The results are displayed via a bank of LEDs, where each LED represents a bit (1 for ON, 0 for OFF).

• Bitwise Mapping: The code uses the bitRead() or bitwise shift operators to set the state of the output LEDs based on the calculated decimal result, providing a clear visual representation of binary-to-decimal conversion and logic state.