freeRTOS for Arduino Uno, Goldilocks 1284p & Mega 2560
A cute and educational x86 OS
x86-64 os made in crystal
A UNIX-like kernel for the i386 architecture
A Development Framework for Coldfire
A Simple 'IDE'A for Linux Kernel Developers
A new OS
Custom firmware and IDE for the VEX Cortex Microcontroller
SuperWikia: The Runtime/Realtime Environment for Codesmiths
MPP is a C-based programming language that allows you to code more eas