"µOS++" (micro OS plus plus) is an open source, royalty-free, real-time operating system intended for embedded systems built around ARM Cortex M or AVR devices. It is based on a preemptive scheduler written in C++ (more info in the Wiki).
Open source project that offer summary and download services on this page is a project that carry out their development work on other open source development sites. Their work is linked to this page via a feature called OFI, and their work is not carried out here on OSDN site.