Open Source Assembly Operating System Kernels

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.

Syllable Desktop is a complete operating system that is easy to use, powerful, lightweight and extraordinarily fast and responsive. It has its own kernel, filesystem, GUI and applications. Syllable Server is a matching small and efficient Linux server.

Visopsys is an alternative operating system for PC compatible computers. In development since 1997, this system is small, fast, and open source. It features a simple but functional graphical interface, pre-emptive multitasking, and virtual memory. Though it attempts to be compatible in a number of ways, Visopsys is not a clone of any other operating system. You can demo the distribution from a “live” CD/DVD or floppy disk

POSIX API for Win2K-XP. Mainly implemented in the driver. Included: write-on-copy fork, threads, mutexes, spins, condvars, rwlocks, signals ... Signals/cancelation interrupt all waitable syscalls, NT syscalls are automaticaly restarted.

The goal of project is to build CMSIS like environment for LPC2000 series MCU and to write RTOS for LPC2000 and Cortex Microcontrollers

Agnix is a small operating system kernel for i386, supporting 32-bit protected memory mode, paging, hardware switched tasks, memory tests, PCI bus, devices, PCI IRQ routing, RT timers and network protocols.

Free and simply RTOS for AVR at assembler. So far, the AVR Studio is used as a development environment. The system supports the preemptive and cooperative multitasking modes, semaphores. Use a small amount of memory for tasks.

FOS - open source 32-bit microkernel operating system.

The FDOS Operaing System is 100% written in Assembler (NASM). It supports FAT 12, TSR and a small Multi Kernel System. The source is very good documentated (only in English). A German, russian and English Documentation (about 40 pages) are included.

GrindarsOS - 32bit protect-mode one-task operating system.

Idioma is an open source object-oriented operation system. Main goals of Idioma project are simplicity and elegance.

MDF is microkernel operating system. Module architecture minimalistic design.

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.

High performance, assembler coded, both desktop and server operating system. Ease of use, ease of programming, joy of power.

An English, German, Japanese, Portuguese, Russian, Chinese, Hindi & Bengali desktop OS loading from miniCD or USB key with applications and personal config files on floppy or USB key.

Tesoro is an open source operating system project fully written in x86 Assembler language. The architecture is partially based on some QNX ideas and some fresh ideas. It combines low level assembler coding (e.g. microkernel with extremely fast task switch

The purpose of objex project resemles GNU project i.e. to develop a complete operating system which is free and open source software. In contrast to the GNU project we are going to build modern system which put together all recent progress in computer

XSystem Kernel Project - an object-oriented 32-bit protected-mode operating system for IA32-architecture.

Yamit - Scalable, Portable and High Performance POSIX complaint OS. Microkernel based Operating System designed for tightly or loosely coupled multiprocessor hardware.

Just another view on how should OS be designed. Streams based architecture, micro kernel, dynamic loading/removing drivers without OS rebooting, ...

JimpOS - Java Implemented Operating System The main purpose of the JimpOS project is realisation of multitasking, platform independent operating system written in Java language.

scmRTOS is tiny Real-Time Preemptive Operating System intended for use with Single-Chip Microcontrollers. scmRTOS is capable to run on small uCs with as little amount of RAM as 512 bytes. The RTOS is written on C++ and supports various platforms.