ChibiOS/RT is a free and efficient RTOS designed for deeply embedded applications. It offers a comprehensive set of kernel primitives and supports many architectures: ARM7, Cortex-M0, Cortex-M3, Cortex-M4, PowerPC e200z, STM8, AVR, MSP430, ColdFire, H8S, x86.
Public Domain Operating System (currently x86 and 80386 and S/370 and S/390)
The AROS Research Operating System is an effort to implement an Open Source and portable operating system that is compatible with AmigaOS(TM). Originally, it was meant as a direct reimplementation, but already has features not existing in AmigaOS.
Free operating system for Atari computers, and more.
EmuTOS is a TOS compatible operating system for Atari ST series computers, and more. It is made from Digital Research's GPLed original sources and is a free and open source alternative to Atari proprietary ROMs.
FreeDOS is a free DOS-compatible operating system.
FreeDOS is a complete, free, DOS-compatible operating system that you can use to play classic DOS games, run legacy business software, or develop embedded systems. Any program that works on MS-DOS should also run on FreeDOS. It doesn’t cost anything to download and use FreeDOS. You can also share FreeDOS for others to enjoy! And you can view and edit our source code, because all FreeDOS programs are distributed under the GNU General Public License or a similar open source software license.
colorForth is, in Chuck Moore's own words: "A dialect of Forth that uses color to replace punctuation. Includes its own operating system. Produces extremely compact programs. Instant compile from pre-parsed source."
QNAP GPL Source
GPL source for QNAP Turbo NAS
Archman-OS / Arch Linux based linux distribution
Archman OS Arch Linux based linux distribution Default Arch Linux, Default Desktop Environments No configuration, No Customization
Free real-time operating system designed for Cortex-M
Free, extremely simple, amazingly tiny and very fast real-time operating system (RTOS) designed for deeply embedded applications. Target: ARM Cortex-M, STM8 families. It was inspired by the concept of a state machine. Procedure executed by the task (task state) doesn't have to be noreturn-type. It will be executed into an infinite loop. There's a dedicated function for immediate change the task state.
Free cooperative operating system designed for Cortex-M
Free, simple and tiny cooperative operating system (OS) designed for deeply embedded applications. Target: ARM Cortex-M, STM8, AVR8 families. It was inspired by the concept of a state machine. Procedure executed by the task (task state) doesn't have to be noreturn-type. It will be executed into an infinite loop. There's a dedicated function for immediate change the task state.
Real-Time Embedded Operating System
Nuttx is a real time embedded operating system (RTOS). Its goals are: (1) small footprint usable in deeply embedded, resource constrained environments, (2) fully scalable from tiny (8-bit) to moderate (32-bit), (3) standards compliance, (4) real time, and (5) totally open. Think "Tiny Linux".
FlashForth is a standalone Forth system for the Microchip PIC 18, 24, 30, 33 and the Atmel Atmega series of microcontrollers. A Forth system with interpreter, compiler, assembler and multitasker is provided.
Cryptic Allusion Dreamcast-related development: KallistiOS, Ghetto Pong, etc.
Open Source SW/HW Project for Embedded Ethernet Applications. Works with AVR ATmega256/128/103, AVR32, SAM7X, SAM7S(E), SAM9, AT91X40, GameBoy Advance, Cortex M3 / M4 (STM32, NXP LPC, LM3S), Freescale Coldfire, RTL8019AS, LAN91C111, CS8900 and DM9000E chips. Offers a tiny TCP/IP stack including HTTP, FTP and DHCP.
Market leading real time kernel for 35+ microcontroller architectures
FreeRTOS is a market leading RTOS kernel from Amazon Web Services that supports more than 35 architectures and was downloaded once every 3 minutes during 2016. With millions of deployments in all imaginable market sectors (from toys to aircraft), the FreeRTOS kernel is trusted because it is professionally developed, strictly quality controlled, robust, supported, free to use in commercial products without a requirement to expose proprietary source code, and has no IP infringement risk. Amazon Web Services provides a highly reliable, scalable, low-cost cloud infrastructure platform that powers hundreds of thousands of businesses in 190 countries around the world. In 2015 AWS added specific Internet of Things (IoT) capabilities, and now offers Amazon FreeRTOS to help users securely connect their MCU devices to the cloud. Learn more at http://aws.amazon.com/freertos. ARM Cortex (Cortex-M0, Cortex-M0+, Cortex-M3, Cortex-M4, Cortex-M7, Cortex-A9, Cortex-A5), Renesas, TI, etc.
OS-9/6809 compatible operating system for Tandy CoCo and Dragon
The NitrOS-9 Project provides an OS-9/6809 compatible operating system for the Tandy/TRS-80 Color Computer and Dragon home computer.
An operating system based on the best Windows NT design principles
ReactOS is an open source effort to develop a quality operating system that is compatible with applications and drivers written for the Microsoft Windows NT family of operating systems (NT4, 2000, XP, 2003).
RTOS for Secure Systems
Pharos is a Real-Time Operating System designed for Secure Systems. Besides having all the nice real-time properties of a RTOS, it also allows the developer to create multiple separate applications (partitions) that cannot damage each other. It allows the developer to create multiple partitions with a set of threads (executed in user mode), where each partition has its own address space and cannot access the area of another partition, following the microkernel philosophy, but still being fast. It also includes many other features (like inter-partition comms). Checkout the wiki page for more info. It is currently developed for ARM (Arm926ej-s and Cortex R5). Cortex M4 port is next. Version 1.1.0 has been released. See https://sourceforge.net/projects/rtospharos/files/1.1.0/ to download. Feel free to contact us at email@example.com
NetFlow iptables module for Linux kernel
ipt-netflow is high performance NetFlow exporting module for Linux kernel (up to 4.4). Designed for Linux router with heavy network load. This is netfilter/iptables module adding support for -j NETFLOW target. Designed to work efficiently w/o conntrack. Supporting NetFlow protocols v5, v9, and IPFIX. Accounting for IPv4, IPv6 traffic, and NAT translation events (NEL). Additional options is SNMP-index translation rules, aggregation rules, Ethernet type, MPLS, VLAN, and MAC addresses exporting.
ELERA İşletim Sistemi
TORO is demonstrating an innovative operating system by integrating at the same ring level both kernel and the user application server. The threads of the user application server are distributed evenly on all CPUs and running independently in parallel. The memory model chosen is NUMA without pagination. During the initialization, the memory is divided proportionally for each processor installed on the system. When a thread needs memory, the memory allocator returns a free block of memory depending on which CPU the thread is running. In the same way, TORO can dedicate resources to specific processor, i.e. a FileSystem. This only CPU then can access to this instance of FileSystem. The scheduler is based on the cooperative threading model, therefore due to this design, TORO can migrate threads between CPUs and send messages between threads without using any lock instruction. TORO is well suited for integrated system to run at high pace application servers like web servers.
Tool kit for building highly secure special-purpose operating systems
The Genode OS Framework is a tool kit for building highly secure special-purpose operating systems. It scales from embedded systems with as little as 4 MB of memory to highly dynamic general-purpose workloads. Genode is based on a recursive system structure. Each program runs in a dedicated sandbox and gets granted only those access rights and resources that are needed for its specific purpose. Programs can create and manage sub-sandboxes out of their own resources, thereby forming hierarchies where policies can be applied at each level. The framework provides mechanisms to let programs communicate with each other and trade their resources, but only in strictly-defined manners. Thanks to this rigid regime, the attack surface of security-critical functions can be reduced by orders of magnitude compared to contemporary operating systems.
Simplest kernel for cooperative multithreading
Simplest of possible ways to multithreading on the smallest microcontrollers. This project is demonstration the programming technique of the multithreading with polling the system state. Published code debugged and ready to use in your projects.