RTOSi

RTOSi is a real-time operating system designed for embedded and IoT devices that require deterministic timing and predictable latency. It provides a preemptive multitasking kernel, priority-based scheduling, and tickless operation to minimize power usage. The kernel is modular, with a core scheduler, inter-task communication primitives, and a hardware abstraction layer that simplifies porting to different microcontrollers and processors.

Key features include memory protection with an MPU, optional memory management, timer services, and robust interrupt handling. RTOSi offers both a native API optimized for low overhead and a POSIX-like API for compatibility, facilitating code reuse across projects. It supports standard IPC mechanisms such as queues, semaphores, event flags, and mailboxes, as well as synchronization and resource locking to prevent priority inversions.

Architecture of RTOSi uses a modular microkernel approach with optional services such as file systems, networking stacks, and device drivers loaded as components. It emphasizes a small footprint, fast context switching, and deterministic interrupt latency. Tooling includes a command-line debugger, trace recorder, and a porting guide for common MCUs and SoCs. The project prioritizes portability, aiming to provide the same API surfaces across ports while allowing architecture-specific optimizations.

RTOSi was first released in 2012 by NovaTech Embedded, with major releases in 2015, 2018, and 2021. It is distributed under the Apache 2.0 license. Development is coordinated on a public repository with community contributions, comprehensive documentation, and a governance model that encourages openness and reproducible builds.

RTOSi is used in robotics, industrial automation, medical devices, consumer electronics, and automotive control units. It provides reference designs, evaluation boards, and verification resources to help teams meet real-time requirements and safety considerations.