Importance of RTOS????

[chandu.kurapati]

Hi,
Any one please describe about what is the need of RTOS over traditional embedded programming.what is the need of RTOS.

How we can achieve concurrency with the RTOS, please explain with in depth example to understand more clearly.

I saw one example about two UART's are filling the data in buffers & application sharing that data, they written some thing about that, but i can not understand it.

please explain little bit deeper for me, to understand the importance of RTOS in the programming point of view.

Thanks & Regards,
Chandu,Kurapati.

 

[andre_luis]

Operating systems working in real time are required for applications heavily dependent of the time basis, such as data acquisition for further image/sound processing, or for local processing if the hardware platform is a DSP core or has a powerful built-in coprocessor.

As one of the basic conditions in these applications is a fixed cadence in the tick of the samples, RTOS aims to achieve that with no additional complexity in the programming framework. This could even be done in a standard OS, but in this case the timer interrupt handling and context retrieving from a stack should be made manually by your code.

 

[matrixofdynamism]

A bare metal code that uses an infinite loop with interrupts is actually sufficient for many tasks. However, as the complexity of the application increases, the loop + interrupts method well fail to effectively carry out all tasks especially of there are timing constraints on the tasks. For example, the processor must read or write data from or to an external device or devices within some time constraints. Using infinite loop with interrupts may be sufficient. However, as the complexity of the problem increases the program will fail. An RTOS will then be needed to save the day. That is why it is an RTOS rather than a standard OS.

The FreeRTOS website explains this concept. It shows a program that uses the bare metal version and then a program that uses the FreeRTOS version to do the same thing. The FreeRTOS version is considerably simpler as most of the complexity is encapsulated by the FreeRTOS itself. Please do have a look at the website of FreeRTOS.