What is the uC/OS task scheduling mechanism?
uCos is an embedded operating system that offers a task scheduling mechanism to manage and schedule the execution of multiple tasks.
In uCos, tasks are independent execution units, each having its own Task Control Block (TCB) to save the task’s status and relevant information. The task scheduler will select the highest priority task from the ready tasks to execute, based on a certain scheduling algorithm.
The task scheduling algorithm of uCos can be divided into two types: preemptive scheduling and cooperative scheduling.
- Preemptive scheduling: In preemptive scheduling, tasks can be forcibly preempted by tasks with higher priorities. uCos offers various scheduling algorithms such as priority scheduling, time-slice round-robin scheduling, etc. which can be selected based on specific needs.
- Collaborative scheduling: In collaborative scheduling, each task voluntarily releases execution rights to allow other tasks to run. uCos provides mechanisms for task delay and suspension, allowing tasks to actively give up execution rights through delay or suspension.
The task scheduler periodically schedules tasks based on their priority and status to determine the next task to be executed. It also offers features such as event notification mechanisms, message queues, etc., for communication and synchronization between tasks.
In summary, the task scheduling mechanism of uCos manages and schedules the execution of multiple tasks through task control blocks. It selects the next task to execute based on priority and status, and offers two scheduling algorithms: preemptive scheduling and cooperative scheduling.
