AsifOS (educational)

AsifOS (educational) is a fully-functioning Operating System from scratch for learning purposes.

Why this project

The wonders of Operating Systems, especially how they are implemented, always fascinated me. I thought about how a software can actually communicate with the hardware, what happens when we press a key in the keyboard and how a process can read it. With this project I am blessed with the knowledge and wonders of Low-Level computing.

Features of AsifOS (educational)

Bootloader implemented in Intel Real Mode (i8086 16-bit), which will be a raw bootable machine code.
Small part of bootloader loading the kernel and the entire kernel implementation in Intel Protected Mode (i80386 32-bit).
The kernel is written in C entirely, the best programming language ever created.
Memory Management using Paging and Heap.
Virtual File Systems.
FAT16 file system implementation.
Hardware level interrupts using Intel's 8259A PIC.
Implementation of Disk Drivers.
PS/2 Keyboard driver.
Implementation of Processes and Threads/Tasks.
Preemptive multi-tasking using Round-Robin schedular algorithm.
Implementation of loading processes from raw binary and 32-bit ELF file format, used by famous OS's like Linux.
Kernel and user space protections.
Kernel Commands with interrupt driven System Calls.
A user space shell program to interact with the Operating System.
Other miscellaneous implementations like TTY and other microarchitecture related stuff.

Note: AsifOS only supports i386 architecture and BIOS boot for now.

How to build

Prerequisite installations:

Linux: Install the i386-elf-toolchain and nasm according to the distro you are using (Good luck with Ubuntu). We need qemu for testing as well.

MacOS: Try nativeos/homebrew-i386-elf-toolchain, install nasm and qemu with regular homebrew formulae. Haven't tested in Macintosh.

Windows: May God have mercy on your soul.

Build and run:

Just invoke run.sh. It will then invoke make to build the entire project generating os.img and then run it with qemu-system-i386.

Demonstrations

This project is not production ready, I did this project for educational purposes only. Check out AsifOS (production), which I am currently working on.

Peace.