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I have always wanted to boot OS from scratch.
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In this project we are bootstraping kernel via a simple boot sector which loads the kernel into memory and switches to 32-bit protected mode from 16-bit real mode and then calls the kernel code.
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Kernel sets up the global descriptor table, interrupt descriptor table, initializes timer, keyboard interrupt and paging.
- Boot from scratch
- Enter 32-bit Protected mode
- Jump from assembly to C
- Interrupt handling
- Keyboard input and output
- A basic libc
- Virtual memory (Paging)
- Ordered array data structure
- Memory Manager
- Basic shell commands
- Multiboot compliant kernel
├── boot
│ ├── boot_sect.asm
│ ├── disk_load.asm
│ ├── gdt.asm
│ ├── print_hex.asm
│ ├── print_string.asm
│ ├── print_string_pm.asm
│ └── switch_to_pm.asm
├── cpu
│ ├── idt.c
│ ├── idt.h
│ ├── interrupt.asm
│ ├── isr.c
│ ├── isr.h
│ ├── ports.c
│ ├── ports.h
│ ├── timer.c
│ ├── timer.h
│ └── types.h
├── cross-compiler.sh
├── drivers
│ ├── keyboard.c
│ ├── keyboard.h
│ ├── screen.c
│ └── screen.h
├── get_kernel_size
├── kernel
│ ├── bootanimation.c
│ ├── bootanimation.h
│ ├── kernel.c
│ ├── kernel_entry.asm
│ ├── kernel.h
│ ├── kshell.c
│ └── kshell.h
├── libc
│ ├── function.c
│ ├── function.h
│ ├── mem.c
│ ├── mem.h
│ ├── ordered_array.c
│ ├── ordered_array.h
│ ├── string.c
│ └── string.h
├── LICENSE
├── linker.ld
├── Makefile
├── memory
│ ├── kheap.c
│ ├── kheap.h
│ ├── paging.c
│ └── paging.h
├── README.md
└── Resources.md
$ sudo apt install nasm # Netwide Assembler
$ sudo apt install qemu-system-x86 # CPU emulator
$ sudo apt install make # Build system
$ ./cross-compiler # Builds the cross compiler
$ make run # Build and Run- Resources
- Writing a Simple Operating System — from Scratch -by Nick Blundell
- https://github.com/cfenollosa/os-tutorial
- https://github.com/acmiitr/KSOS
- http://www.brokenthorn.com/Resources/OSDevIndex.html
- http://www.jamesmolloy.co.uk/tutorial_html/
- https://wiki.osdev.org/Meaty_Skeleton