ATmega328P Bare-Metal C

A collection of bare-metal C programs for the Arduino Uno (ATmega328P). This repository documents my journey of learning embedded systems from the ground up, bypassing the Arduino IDE and high-level libraries to directly manipulate hardware registers.

🧠 Why Bare Metal?

While frameworks like the Arduino core are excellent for rapid prototyping, they obscure the underlying hardware architecture. This repository is dedicated to mastering silicon-level programming by:

• Reading the Datasheet: Translating ATmega328P datasheet specifications directly into C code.
• Direct Register Manipulation: Controlling peripherals (GPIO, Timers, ADC, UART) via memory-mapped registers.
• Understanding the Build Process: Managing compilation, linking, and flashing manually using standard GNU toolchains rather than clicking "Upload" in an IDE.
• Optimizing Performance: Writing deterministic, highly efficient code with minimal overhead.

🛠️ Hardware Requirements

• Development Board: Arduino Uno Rev3 (or any ATmega328P-based board)
• Peripherals: LEDs, resistors (220Ω - 330Ω), jumper wires, breadboard
• Interface: Standard USB Type-A to Type-B cable

💻 Toolchain Setup

To build and flash these programs, you will need the AVR GCC toolchain and AVRDUDE.

For Linux (Debian/Ubuntu):

sudo apt-get update
sudo apt-get install gcc-avr binutils-avr avr-libc avrdude make