What Is Real Time Operating System?

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What Is Real Time Operating System?
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What is a real time operating system and how does it work? A real-time operating system, also called RTOS, is a type of operating system that revolves around two key features that it has, that is determinism and predictability. 

In the RTOS, few repetitive tasks are performed inside the system, and it operates in quite a tight time cycle and boundary. It has a general purpose as the operating system, but a few key factors that make it quite different compared with other operating system. 


So, What Is RTOS?

RTOS, or real time operating system isn’t quite similar to any other operating system like Windows, Linux, or iOS. The RTOS is an operating system that is based on repeated tasks, with the features of determinism, as well as predictability. In general, the purpose of the real time operating system is to do several repetitive tasks within a tight time boundary.

The RTOS itself is also divided into “Soft” RTOS and “Hard” RTOS, and each of the systems operates within the millisecond’s timeframe, so compared to human reactions, these can be a bit overwhelming, and that is soft RTOS. As for hard RTOS, it provides responses and tasks with low digit milliseconds or any less. 

How Does It Work?

Generally, RTOS work by creating and doing repetitive tasks, and all of it is within a very tight time boundary that could span milliseconds. Different from the general operating system, where the time boundary can be varies depending on the task, the RTOS time boundary needs to be done ASAP, and on the scale of human reaction, it is done within a few milliseconds. 

The main characteristics of RTOS are determinism, predictability, high-end performance, and priority-based scheduling on its system.

Read more : RTOS in Embedded Systems (Microcontrollers)

The Characteristics Of RTOS

Let’s take a look at the characteristics of the RTOS itself shall we:

  • Determinism: It gives repeating input, and with similar output, as similar, as possible, with less than 0.1% margin of difference or error.
  • High-end performance: it gives fast, responsive, and could execute actions within a very small milliseconds timeframe, compared with any other general operating system
  • Priority-based scheduling system: any of its actions would then be assigned as a high priority, and it will be executed first when there is more than one operating system inside one integrated big system. 
  • Predictability: with the same input, comes in with the very same, and predictable output, with very little margin of errors allowed in one system
  • Safety and security: RTOS frequently only be used as a critical system, very important, and any failures would have resulted in disaster. As such, this system needs to have higher safety and security compared with another general operating system. 

So, that’s it on the explanation about what is real time operating system and how does it work. As we have mentioned earlier, you can find the use of RTOS in many assembly factories, such as car factories. This is because it needs a fast, inhumane response time to produce on the scale of an assembly factory, and to do that, there would need an RTOS.

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