5 Essential RTOS Functionalities You May Not Know About

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5 Essential RTOS Functionalities You May Not Know About A real-time operating system (RTOS) has a variety of different functionalities that enable its operations. These include a priority based scheduler, deterministic behavior, system clock interrupt routine, RTOS service, and synchronization and messaging. Priority based scheduler Under the priority based scheduler, a single real-time operating system process is implemented with 32 to 256 possible priorities. The priority scheduler is designed to run processes under the highest possible priority. For instance, if a task is running on a CPU, the next highest priority task will run automatically, and the process continues. The highest priority tasks close the CPU it runs, and once the original task is pre-empted by a new task, the high priority project is made ready. Tasks under the priority based scheduler are classified in three states: ready to run, running and blocked.

Ready to run: this is when a process has all the required resources to run, but it should not be in a running state. Running: Running a task is said to be running if it is under execution. Blocked: Blocked a task that does not have enough necessary resources for a successful execution is sent to a blocked state. Scheduling techniques: The priority based scheduler relies on three task scheduling techniques cooperating scheduling, round robin scheduling, and preemptive scheduling. Under cooperating scheduling, tasks run until their execution is accomplished. Round robin scheduling assigns a fixed time to each process and the process must be completed within the time slot or its data generation and flow are lost. Preemptive scheduling entails allocating time to time-dependent priority tasks. The 256 priority levels are considered and each task is assigned a unique priority level.


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