Apollo Kernel - x86_64 Operating System

A x86_64 operating system kernel with a cool architecture, improved input handling, and modular design. This implementation maintains visual compatibility with previous versions while featuring an entirely new codebase built from the ground up.

From Scratch (This wouldn't exist if someone didn't treatin a DMCA takedown <3 thank you<3)

Architecture Overview

Core Design Principles

• Modular Component Architecture: Cleanly separated subsystems with well-defined interfaces
• Enhanced Memory Management: Heap allocator with block coalescing and alignment
• Robust Input Handling: PS/2 keyboard driver with proper interrupt management
• Layered System Design: Clear separation between hardware abstraction and kernel logic

System Components

• Terminal Subsystem: Hardware-abstracted VGA text mode with advanced color management
• Input Manager: Buffered keyboard input with state tracking and scan code conversion
• Command Processor: Interactive shell with history management and command parsing
• Memory Allocator: Dynamic heap management with fragmentation prevention
• Time Keeper: Real-time clock interface with date/time functionality

Features

Updated Functionality

• Improved Keyboard Input: Fixed input handling with proper buffering and state management
• Advanced Shell System: Command history, tab completion, and enhanced user interaction
• Better Memory Management: Efficient allocation strategies with automatic defragmentation
• Robust Error Handling: Input validation and graceful error recovery
• Hardware Abstraction: Clean separation between hardware-specific and generic code

Technical Improvements

• 64-bit Native Design: Full x86_64 long mode implementation
• Multiboot2 Compliance: Enhanced bootloader compatibility
• Modular Build System: Organized source tree with logical component separation
• Enhanced Documentation: Inline documentation and API specifications

Building the Kernel

Prerequisites

# Ubuntu/Debian
sudo apt update
sudo apt install build-essential nasm qemu-system-x86 grub-pc-bin grub-common xorriso

# Cross-compiler setup
wget https://github.com/lordmilko/i686-elf-tools/releases/download/7.1.0/x86_64-elf-tools-linux.zip
unzip x86_64-elf-tools-linux.zip
export PATH=$PATH:$(pwd)/bin

Compilation

# Build complete kernel
make all

# Run in QEMU emulator
make run

# Debug with GDB
make debug

# Clean build artifacts
make clean

# Show build information
make info

# Validate
make verify

System Architecture

Boot Sequence

1. Multiboot2 Header: GRUB bootloader integration
2. 32-bit Bootstrap: Initial CPU setup and verification
3. Long Mode Transition: Switch to 64-bit execution
4. Subsystem Initialization: Component startup sequence
5. Shell Activation: Interactive user environment

Memory Layout

• Kernel Space: 1MB+ physical address mapping
• Heap Region: 16MB dynamic allocation area
• Stack Space: 64KB kernel execution stack
• Page Tables: Identity-mapped 1GB address space

Input/Output Architecture

• VGA Text Mode: 80x25 character display with full color support
• PS/2 Keyboard: Enhanced driver with proper interrupt handling
• Serial Interface: Debug output capability for development

Commands Reference

Command	Description	Example Usage
help	Display available commands	help
shell	Enter advanced shell mode	shell
clear	Clear screen	clear
echo	Display text	echo Hello World
date	Show current date/time	date
calc	Basic arithmetic calculator	calc 15 + 25
meminfo	Memory usage statistics	meminfo
sysinfo	System information	sysinfo
history	Show command history	history
palette	Color palette demonstration	palette
uptime	System uptime	uptime
reboot	Restart system	reboot
shutdown	Halt system	shutdown

Example images

Calculator Examples

apollo> calc 100 + 50
Result: 100 + 50 = 150

apollo> calc 256 / 8
Result: 256 / 8 = 32

apollo> calc 25 * 4
Result: 25 * 4 = 100

Development and Debugging

Running on Real Hardware

# Create bootable USB drive
sudo dd if=distribution/apollo.iso of=/dev/sdX bs=4M status=progress conv=fsync
# Replace /dev/sdX with your USB device

Debug Information

# Boot with debugging symbols
qemu-system-x86_64 -cdrom apollo.iso -s -S -monitor stdio

# In another terminal, connect GDB
gdb distribution/apollo.bin
(gdb) target remote localhost:1234
(gdb) continue

Technical Specifications

• Architecture: x86_64 (AMD64/Intel 64)
• Boot Protocol: Multiboot2
• Memory Model: 64-bit flat memory with paging
• Graphics: VGA text mode 80x25 with 16-color palette
• Input: PS/2 keyboard with full modifier support
• Build System: GNU Make with cross-compilation
• Languages: C99, x86_64 Assembly
• Toolchain: GCC cross-compiler, NASM assembler

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Apollo Kernel - x86_64 Operating System Technology