OSE
The ENEA OSE real-time operating system first released in 1985.
The Enea multi core family of real-time operating systems was first released in 2009.
The Enea Operating System Embedded (OSE) is a family of real-time, microkernel, embedded operating system created by Bengt Eliasson for ENEA AB, which at the time was collaborating with Ericsson to develop a multi-core system using Assembly, C, and C++. Enea OSE Multicore Edition is based on the same microkernel architecture. The kernel design that combines the advantages of both traditional asymmetric multiprocessing (AMP) and symmetric multiprocessing (SMP). Enea OSE Multicore Edition offers both AMP and SMP processing in a hybrid architecture. OSE supports many processors, mainly 32-bit. These include the ColdFire, ARM, PowerPC, and MIPS based system on a chip (SoC) devices.
The Enea OSE family features three OSs: OSE (also named OSE Delta) for processors by ARM, PowerPC, and MIPS, OSEck for various DSP's, and OSE Epsilon for minimal devices, written in pure assembly (ARM, ColdFire, C166, M16C, 8051). OSE is a closed-source proprietarily licensed software released on 20 March 2018. OSE uses events (or signals) in the form of messages passed to and from processes in the system. Messages are stored in a queue attached to each process. A link handler mechanism allows signals to be passed between processes on separate machines, over a variety of transports. The OSE signalling mechanism formed the basis of an open-source inter-process kernel design project named LINX.