In general, an operating system is designed to manage system resources to meet the demands of different applications. An OS also has some essential elements, including a process scheduler, task manager, memory management, system interface, file systems, multitasking, synchronization, interrupt, event handling, timers and clocks, I/O, and inter-task communication.
On the other hand, a real-time operating system is a type of operating system designed for devices and systems that need to respond in real-time to a trigger very quickly. For instance, in case of software fail-safe, an RTOS will pre-empt lower-priority processes and carry out higher-priority tasks first.
Another great example to understand the purpose and need for an RTOS is the LiDAR and video imaging that autonomous vehicles implement when the car goes down a highway without straying the marked lines or hitting anything. In such a case where a machine or system is given life-safety responsibilities, the higher chances are that it has an RTOS so that a processor can make decisions quickly.
In previous times, the world of embedded systems was full of MCUs because of the high price of performance computing and simple control loops were enough. In today’s time, the embedded world comprises every level from single loop controllers to extremely quick, process-laden, and complex systems.
When do we need an RTOS?
An RTOS becomes a must when there are a wide range of processes and devices and the timing of processes is more critical than average performance. Since a real-time operating system can guarantee the timing requirements for processes it is running, has low latency, and is predictable as it can determine a task’s completion time with certainty, it is the best choice for time-critical applications. What’s more, it enables the existence of both time-critical and non-time-critical tasks.
This type of OS can effectively handle interrupts depending on priority and better control scheduling. Unlike a traditional OS, an RTOS is designed to meet computation deadlines no matter how worse the situation gets for the RTOS.
If you can’t decide whether you should use a PC RTOS or not, here are some of the most common reasons why RTOS is preferred and when:
- You need a real-time response.
You don’t always need an RTOS but if you want real-time response for a time-critical system or application, RTOS is a better choice.
- You need to develop a certified embedded system.
Some certifications require using RTOS to handle the tasks of embedded systems where even a small delay can lead to huge losses.
- You need to develop a time-critical system.
As an RTOS provides a deterministic, hard, real-time response to respond to events in real-time, it makes a great choice when you are designing a system that is given life-safety responsibilities. It is expected to be quick and accurate when it resides in a PC or an embedded system.
When buying a PC RTOS, make sure that you consider some important factors such as responsiveness, safety certifications, available system resources, openness, security, and compatibility.
