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OS<!----></a></div><div class="vp-navbar-item"><a class="route-link auto-link" href="/acronyms/" aria-label="Computing Acronyms"><!---->Computing Acronyms<!----></a></div><!--]--></nav><!--[--><!--]--><ul class="vp-sidebar-items"><!--[--><li><a class="route-link route-link-active auto-link vp-sidebar-item vp-sidebar-heading active" href="/osdev/" aria-label="Fusion OS"><!---->Fusion OS<!----></a><ul style="" class="vp-sidebar-children"><!--[--><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/01-intro" aria-label="Writing an OS in Nim"><!---->Writing an OS in Nim<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/02-environment-setup" aria-label="Environment Setup"><!---->Environment Setup<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/03-targeting-uefi-p1" aria-label="Targeting UEFI (Part 1)"><!---->Targeting UEFI (Part 1)<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/04-targeting-uefi-p2" aria-label="Targeting UEFI (Part 2)"><!---->Targeting UEFI (Part 2)<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/05-bootloader-p1" aria-label="UEFI Bootloader (Part 1)"><!---->UEFI Bootloader (Part 1)<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/06-bootloader-p2" aria-label="UEFI Bootloader (Part 2)"><!---->UEFI Bootloader (Part 2)<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/07-kernel-image" aria-label="Kernel Image"><!---->Kernel Image<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/08-loading-the-kernel-p1" aria-label="Loading the Kernel (Part 1)"><!---->Loading the Kernel (Part 1)<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/09-loading-the-kernel-p2" aria-label="Loading the Kernel (Part 2)"><!---->Loading the Kernel (Part 2)<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/10-loading-the-kernel-p3" aria-label="Loading the Kernel (Part 3)"><!---->Loading the Kernel (Part 3)<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/11-physical-memory" aria-label="Physical Memory"><!---->Physical Memory<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/12-virtual-memory" aria-label="Virtual Memory"><!---->Virtual Memory<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/13-higher-half-kernel" aria-label="Higher Half Kernel"><!---->Higher Half Kernel<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/14-memory-segments" aria-label="Memory Segments"><!---->Memory Segments<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/15-interrupts" aria-label="Interrupts"><!---->Interrupts<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/16-user-mode" aria-label="User Mode"><!---->User Mode<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/17-tss" aria-label="Task State Segment"><!---->Task State Segment<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/18-system-calls" aria-label="System Calls"><!---->System Calls<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/19-tasks" aria-label="Tasks"><!---->Tasks<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/20-position-independent-code" aria-label="Position Independent Code"><!---->Position Independent Code<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/21-elf-loader-p1" aria-label="ELF Loader (Part 1)"><!---->ELF Loader (Part 1)<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/22-elf-loader-p2" aria-label="ELF Loader (Part 2)"><!---->ELF Loader (Part 2)<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/23-coop-multitasking" aria-label="Cooperative Multitasking"><!---->Cooperative Multitasking<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/24-system-library" aria-label="System Library"><!---->System Library<!----></a><!----></li><li><a class="route-link auto-link vp-sidebar-item" href="/osdev/25-interrupt-controller" aria-label="Interrupt Controller"><!---->Interrupt Controller<!----></a><!----></li>

40<!--]--></ul></li><!--]--></ul><!--[--><!--]--></aside><!--]--><!--[--><main class="vp-page"><!--[--><!--]--><div class="theme-default-content" vp-content><!--[--><!--]--><div><h1 id="fusion-os" tabindex="-1"><a class="header-anchor" href="#fusion-os"><span>Fusion OS</span></a></h1><p>This is both a documentation and a tutorial for building an operating system, Fusion OS, from scratch in Nim. You can find the source code on GitHub at <a href="https://github.com/khaledh/fusion" target="_blank" rel="noopener noreferrer">https://github.com/khaledh/fusion</a>.</p><blockquote><p>Note: The source for this documentation is on GitHub at <a href="https://github.com/khaledh/khaledh.github.io" target="_blank" rel="noopener noreferrer">https://github.com/khaledh/khaledh.github.io</a>. Comments and contributions are welcome through GitHub issues and pull requests.</p></blockquote><h2 id="screenshots" tabindex="-1"><a class="header-anchor" href="#screenshots"><span>Screenshots</span></a></h2><p><strong>UEFI Bootloader</strong></p><p><img src="/assets/boot-exitbootservices-Dt2Rlx1o.png" alt="UEFI Bootloader"></p><p><strong>GUI</strong> (<em>Note: This screenshot is from the <code>graphics</code> branch, which is still a work-in-progress.</em>)</p><p><img src="/assets/screenshot-graphics-DH5ICI7A.png" alt="Screenshot from the graphics branch"></p><p><strong>Booting and Running the Kernel</strong></p><p><img src="/assets/screenshot-kernel-booting-DtYqTorQ.png" alt="Booting and Running Fusion Kernel"></p><h2 id="features" tabindex="-1"><a class="header-anchor" href="#features"><span>Features</span></a></h2><p>The following features are currently implemented:</p><ul><li>UEFI Bootloader</li><li>Memory Management <ul><li>Single Address Space</li><li>Physical Memory Manager</li><li>Virtual Memory Manager</li><li>Higher Half Kernel</li></ul></li><li>Task Management <ul><li>Kernel Tasks</li><li>User Mode Tasks</li><li>Preemptive Multitasking</li><li>Priority-based Scheduling</li><li>ELF Loader</li></ul></li><li>System Calls <ul><li>System Call Interface</li><li>SYSCALL/SYSRET</li><li>User Mode Library</li></ul></li><li>IPC <ul><li>Synchronization Primitives</li><li>Channel-based IPC</li><li>Message Passing</li></ul></li><li>Hardware <ul><li>Timer Interrupts</li><li>PCI Device Enumeration</li><li>Bochs Graphics Adapter Driver</li></ul></li></ul><h4 id="planned" tabindex="-1"><a class="header-anchor" href="#planned"><span>Planned</span></a></h4><ul><li>Capability-based Security</li><li>Event-based Task State Machines</li><li>Demand Paging</li><li>Disk I/O</li><li>File System</li><li>Keyboard/Mouse Input</li><li>Shell</li><li>GUI</li><li>Networking</li></ul></div><!--[--><!--]--></div><footer class="vp-page-meta"><!----><div class="vp-meta-item git-info"><div class="vp-meta-item last-updated"><span class="meta-item-label">Last Updated: </span><!----></div><!----></div></footer><!----><!--[--><!--]--></main><!--]--></div><!--[--><!----><!----><!--]--><!--]--></div>
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