operating system

51 Articles

A RISC-V Operating System Instruction Manual

May 26, 2025 by 1 Comment

To some, an operating system is a burden or waste of resources, like those working on embedded systems and other low-power applications. To others it’s necessary, abstracting away hardware so that higher-level programming can be done. For most people it’s perhaps not thought of at all. But for a few, the operating system is the most interesting piece of software running on a computer and if you’d like to investigate what makes this often overlooked aspect of computer science interesting, take a look at this course on operating systems from Cornell University.

The operating system itself is called Earth and Grass Operating System because it splits the functionality of the operating system into three separate parts. The Earth layer involves dealing with hardware, the Grass layer involves hardware-independent aspects, and a third application layer implements other key operating system features. It’s built for a RISC-V processor, since that instruction set is completely open source and transparent about what it’s doing. It’s also incredibly small, coming in at around 2000 lines of code. The course covers nine areas, with the first six being core operating system functions and the remaining three covering more advanced operating system concepts.

For understanding the intricacies and sometimes mysterious ways that operating systems work, a course like this can go a long way into unraveling those mysteries and developing a deeper understanding of how it brings the hardware to work for higher-level software. We actually featured this operating system two years ago, before this course was created, which covers this project for those who like to take a more self-directed approach, or simply want a lightweight OS for a RISC-V system.

Mockup of a printed copy of the Little OS Book

One Book To Boot Them All

April 2, 2025 by 19 Comments

Somewhere in the universe, there’s a place that lists every x86 operating system from scratch. Not just some bootloaders, or just a kernel stub, but documentation to build a fully functional, interrupt-handling, multitasking-capable OS. [Erik Helin and Adam Renberg] did just that by documenting every step in The Little Book About OS Development.

This is not your typical dry academic textbook. It’s a hands-on, step-by-step guide aimed at hackers, tinkerers, and developers who want to demystify kernel programming. The book walks you through setting up your environment, bootstrapping your OS, handling interrupts, implementing virtual memory, and even tackling system calls and multitasking. It provides just enough detail to get you started but leaves room for exploration – because, let’s be honest, half the fun is in figuring things out yourself.

Completeness and structure are two things that make this book stand out. Other OS dev guides may give you snippets and leave you to assemble the puzzle yourself. This book documents the entire process, including common pitfalls. If you’ve ever been lost in the weeds of segmentation, paging, or serial I/O, this is the map you need. You can read it online or fetch it as a single 75-page long PDF.

Mockup photo source: Matthieu Dixte

Help Propel The Original ARM OS Into The Future

March 30, 2025 by 33 Comments

We use ARM devices in everything from our microcontroller projects to our laptops, and many of us are aware of the architecture’s humble beginnings in a 1980s Acorn Archimedes computer. ARM processors are not the only survivor from the Archimedes though, its operating system has made it through the decades as well.

RISC OS is a general purpose desktop operating system for ARM platforms that remains useful in 2025, as well as extremely accessible due to a Raspberry Pi port. No software can stand still though, and if RISC OS is to remain relevant it must move with the times. Thus RISC OS Open, the company behind its development, have launched what they call a Moonshots Initiative, moving the OS away from incremental development towards much bolder steps. This is necessary in order for it to support the next generation of ARM architectures.

We like RISC OS here at Hackaday and have kept up to date with its recent developments, but even we as fans can see that it is in part a little dated. From the point of view of RISC OS Open though, they identify support for 64-bit platforms as their highest priority, and to that end they’re looking for developers, funding partners, and community advocates. If that’s you, get in touch with them!

Tactility; The ESP32 Gets Another OS

January 11, 2025 by 14 Comments

Doing the rounds this week is a new operating system for ESP32 microcontrollers, it’s called Tactility, and it comes from [Ken Van Hoeylandt]. It provides a basic operating system level with the ability to run apps from an SD card, and it has the choice of a headless version or an LVGL-based touch UI.

Supported devices so far are some Lillygo and M5Stack boards, with intriguingly, support in the works for the Cheap Yellow Display board that’s caught some attention recently. The term “ESP32” is now a wide one encompassing Tensilica and RISC-V cores and a range of capabilities, so time will tell how flexible it is for all branches of the family.

We find this OS to be interesting, both in its own right and because it joins at least two others trying to do the same thing. There’s [Sprite_TM]’s PocketSprite mini console, and the operating system used by the series of Netherlands hacker camp badges,  We’ll be trying to get a device running it, in order to give you a look at whether it’s suitable for your projects. If it runs well on the cheaper hardware, it could be a winner!

Writing A RISC-V OS From Scratch

January 9, 2025 by 15 Comments

If you read Japanese, you might have seen the book “Design and Implementation of Microkernels” by [Seiya Nuda]. An appendix covers how to write your own operating system for RISC-V in about 1,000 lines of code. Don’t speak Japanese? An English version is available free on the Web and on GitHub.

The author points out that the original Linux kernel wasn’t much bigger (about 8,500 lines). The OS allows for paging, multitasking, a file system, and exception handling. It doesn’t implement interrupt handling, timers, inter-process communication, or handling of multiple processors. But that leaves you with something to do!

The online book covers everything from booting using OpenSBI to building a command line shell. Honestly, we’d have been happier with some interrupt scheme and any sort of crude way to communicate and synchronize across processes, but the 1,000 line limit is draconian.

Since the project uses QEMU as an emulation layer, you don’t even need any special hardware to get started. Truthfully, you probably won’t want to use this for a production project, but for getting a detailed understanding of operating systems or RISC-V programming, it is well worth a look.

If you want something more production-ready, you have choices. Or, stop using an OS at all.

Haiku OS’s Beta 5 Release Brings Us Into A New BeOS Era

October 30, 2024 by 28 Comments

The name BeOS is one which tends to evoke either sighs of nostalgia or blank stares, mostly determined by one’s knowledge of the 1990s operating system scene. Originally released in 1995 by Be Inc., it was featured primarily on the company’s PowerPC-based BeBox computers, as well as being pitched to potential customers including Apple, who was looking for a replacement for MacOS. By then running on both PowerPC and x86-based systems, BeOS remained one of those niche operating systems which even the free Personal Edition (PE) of BeOS Release 5 from 1998 could not change.

As one of the many who downloaded BeOS R5 PE and installed it on a Windows system to have a poke at it, I found it to be a visually charming and quite functional OS, but saw no urgent need to use it instead of Windows 98 SE or 2000. This would appear to have been the general response from the public, as no BeOS revival ensued. Yet even as BeOS floundered and Be Inc. got bought up, sold off and dissected for its parts, a group of fans who wanted to see BeOS live on decided to make their own version. First called OpenBeOS and now Haiku, it’s a fascinating look at a multimedia-centric desktop OS that feels both very 1990s, but also very modern.

With the recent release of the R1 Beta 5 much has been improved, which raises the interesting question of how close Haiku is to becoming a serious desktop OS contender.

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FreeBSD At 30: The History And Future Of The Most Popular BSD-Based OS

October 28, 2024 by 40 Comments

Probably not too many people around the world celebrated November 1st, 2023, but on this momentous date FreeBSD celebrated its 30th birthday. As the first original fork of the first complete and open source Unix operating system (386BSD) it continues the legacy that the Berkeley Software Distribution (BSD) began in 1978 until its final release in 1995. The related NetBSD project saw its beginnings somewhat later after this as well, also forking from 386BSD. NetBSD saw its first release a few months before FreeBSD’s initial release, but has always followed a different path towards maximum portability unlike the more generic nature of FreeBSD which – per the FAQ – seeks to specialize on a limited number of platforms, while providing the widest range of features on these platforms.

This means that FreeBSD is equally suitable for servers and workstations as for desktops and embedded applications, but each platform gets its own support tier level, with the upcoming version 15.x release only providing first tier support for x86_64 and AArch64 (ARMv8). That said, if you happen to be a billion-dollar company like Sony, you are more than welcome to provide your own FreeBSD support. Sony’s Playstation 3, Playstation 4 and Playstation 5 game consoles namely all run FreeBSD, along with a range of popular networking and NAS platforms from other big names. Clearly, it’s hard to argue with FreeBSD’s popularity.

Despite this, you rarely hear people mention that they are running FreeBSD, unlike Linux, so one might wonder whether there is anything keeping FreeBSD from stretching its digital legs on people’s daily driver desktop systems?

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