This is the repository for all my Arduino simulation and hardware projects

1. The Arduino Matrix Calculator 🧮

A tactile arithmetic experience powered by ATmega328P

A simple, robust calculator that handles the basics without the distraction of an OS.

🧐 Why I Built This

I wanted to understand the raw logic behind input processing. Instead of using a phone calculator, I built one from scratch to learn about matrix scanning, state management, and LCD driver communication.

⚡ Features

• Arithmetic Core: Handles Addition, Subtraction, Multiplication, and Division.
• Continuous Calculation: Chain operations (e.g., 5 + 5 then + 2 uses the previous result).
• Error Handling: Catches division by zero errors.
• Reset on Demand: Dedicated C button to wipe the memory.

🔌 Pinout & Wiring

The code uses specific pin mappings. If you are using an Arduino Uno, note that Pins 14-17 correspond to Analog Pins A0-A3.

Component	Component Pin	Arduino Pin	Notes
LCD Display	RS	D12
	E (Enable)	D11
	D4	D10
	D5	D9
	D6	D8
	D7	D7
Keypad	Row 1 - 4	D2, D3, D4, D5
	Col 1	A3 (D17)	Leftmost column
	Col 2	A2 (D16)
	Col 3	A1 (D15)
	Col 4	A0 (D14)	Rightmost column

🛠️ How to Run

1. Clone this repository.
2. Open calculator.ino in the Arduino IDE.
3. Install the required libraries via Library Manager (Ctrl+Shift+I):
   • Keypad by Mark Stanley
   • LiquidCrystal (Built-in)
4. Connect your Arduino and hit Upload.

🎮 Controls

Key	Function
0-9	Enter Numbers
A	+ (Add)
B	- (Subtract)
C	× (Multiply)
D	÷ (Divide)
#	= (Result)
*	Clear (Reset)

Found this useful? ⭐ Give this repo a Star!

Developed with ❤️ by Shoumik Islam AKA Base21rizz