PEENOS

Pi Exploration & Experimentation for Noobs Operating System

Welcome to PEENOS, a lightweight, baremetal operating system built for the Raspberry Pi 3B! PEENOS is designed to empower hobbyists, students, and developers with a simple yet functional environment for exploring the fundamentals of operating system development.

Whether you're experimenting with hardware, diving into low-level programming, or simply curious about how operating systems work, PEENOS is your gateway to hands-on learning.

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Features

• Baremetal Architecture: PEENOS runs directly on the hardware, without any underlying OS.
• ARMv8 Support: Optimized for the ARM Cortex-A53 architecture of the Raspberry Pi 3B.
• Custom Memory Management: Includes a basic memory management unit (MMU) and paging system.
• Peripheral Support: Built-in drivers for SD cards, timers, and FAT file systems.
• Command Shell: Execute basic commands through an intuitive custom shell.
• Interrupt Handling: Robust exception and interrupt handling mechanisms.
• Minimalist Design: Focused on clarity and simplicity for educational purposes.

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Directory Structure

├── src
│   ├── arch
│   │   └── arm
│   │       ├── boot.s
│   │       └── vector_table.s
│   ├── commands
│   │   ├── cmd
│   │   └── cmds.c
│   ├── drivers
│   │   ├── fat.c
│   │   ├── sd.c
│   │   └── systimer.c
│   ├── kernel
│   │   ├── exceptions
│   │   │   ├── exc.c
│   │   │   └── interrupt.c
│   │   ├── kernel_main.c
│   │   ├── mmu.c
│   │   └── page.c
│   └── libc
│       ├── delays.c
│       ├── pLib.c
│       └── rprintf.c
├── obj
│   └── (compiled object files)
├── include
│   └── (header files)
├── kernel.ld
├── Makefile
└── README.md

Getting Started

Requirements

• Raspberry Pi 3B
• Cross-compiler for ARM (e.g., aarch64-linux-gnu-gcc)
• QEMU (for emulation and debugging)
• GNU Make