Complex-OS

About

An x86 operating system written from scratch in C and Assembly for ITBA's Operating Systems course. It covers the full path from power-on to a running kernel: a custom bootloader hands control to a kernel that sets up the low-level plumbing the rest of the system depends on.

Key Features

• A custom bootloader that prepares the CPU and loads the kernel into memory.
• A kernel entry point bridging the Assembly boot stage and the C runtime.
• Low-level interrupt and device handling to reach an interactive state.
• A Makefile-driven build that produces a bootable disk image.

Technical Challenges

• Transitioning the CPU from 16-bit real mode into 32-bit protected mode during boot.
• Coordinating the handoff between Assembly and C across the boot boundary.
• Debugging at the hardware level with no operating system underneath to lean on.

Impact & Results

Built first-hand intuition for the hardware/software boundary — from the bootloader up to a running kernel.

Technologies Used