what is the difference between RTOS and (assembly or c) code

[neduva]

hi friends i have a doubt. please clarify this.
by using (c or assembly) we can create program to run in 8051 or any other controller means. what is the benifit of using rtos?
why RTOS is most powerfull tool.

---------- Post added at 17:50 ---------- Previous post was at 17:48 ----------

i'm asking this to know, what exactly rtos is? and how to practice this?

 

[bhav]

C is higher level language. the code written is for general operating system with latency.

In RTOS code is optimized for that particular hardware for which real-time operating system is designed. the through put is increased with more tighter timing control of the hardware components.

 

[neduva]

ok. Can you tell me how to learn RTOS. is there any simple project to learn about RTOs.

 

[rohitkhanna]

Hmmm.... you are comparing apples with oranges.

C and other languages are how you specify exactly what actions a particular processor must to, down to the last details.

RTOS is a general name for "Real Time Operating System". This means that is a pre-built set of code which MANAGES the processor for you (the "Operating System" part), and has the capability to react to real-world signals immediately (the "Real-Time" part).

So an RTOS makes life simpler for a C programmer by providing all sorts of built-in functions etc. For example - timer management, memory management, interrupt management, etc.

making any sense ?
cheers!

 

[sachin_im]

Hello

As everyone told you that RTOS is real time operating system, actually role of RTOS comes when you need multi tasking in your system and you have to priorities your task. Here you consider task as your c function. Means suppose there are three function in your code written for specific applications and you want each function to work in parallel. Then RTOS will able to allow you to convert your traditional functions into tasks and will schedule them as per priority of tasks.
You can refer following presentation on RTOS for more information…
Following links may be useful for you.

http://www.embeddedcraft.org/RTOS Part1.pdf
http://www.embeddedcraft.org/RTOS Part2.pdf
http://www.embeddedcraft.org

hi friends i have a doubt. please clarify this.
by using (c or assembly) we can create program to run in 8051 or any other controller means. what is the benifit of using rtos?
why RTOS is most powerfull tool.

---------- Post added at 17:50 ---------- Previous post was at 17:48 ----------

i'm asking this to know, what exactly rtos is? and how to practice this?

 

[neduva]

means we can do different task in same clock cycle. and we cannot do this using normal c language. is it so?

Here you consider task as your c function. Means suppose there are three function in your code written for specific applications and you want each function to work in parallel. Then RTOS will able to allow you to convert your traditional functions into tasks and will schedule them as per priority of tasks.

 

[bhav]

sahin_im is right

 

[neduva]

ya i have gone through that pdf. it shows an example.i cant find the difference between that two programing. so can you please elaborate that programing. if possible give your own example program.

 

[sachin_im]

The difference is that functions are now threads. For create a threads we need function. There are API to create threads, in which function is a parameter. Apart from functions there are other parameters also. API is nothing but a set of functions specific to RTOS or OS.

 

[neduva]

I understood the concept of RTOS. but i'm scared of start doing. my confusions are 1) like c, java,asm.... is RTOS a separate predefind coding command? 2)if so. how to learn that? 3) Can we use same keyword to program all the controller?

 

[bigdogguru]

i'm asking this to know, what exactly rtos is? and how to practice this?

Your in luck. One of the foremost texts on RTOS:

Patterns for Time-Triggered Embedded Systems

Which has been out-of-print for sometime, has been released on PDF by the author Michael Pont.

You can download the text free of charge, directly from the author's website:

Patterns for Time-Triggered Embedded Systems

Although the texts code examples are based on the 8051, they can be readily ported to almost any microcontroller.

At a thousand pages, the text is a real gem, packed cover to cover with information concerning RTOSs and their development.


BigDog

 

[milind.a.kulkarni]

I will like to share one point here-

In context of real time operating system.... either be it any thing from RTlinux to FreeRTOS the task given to operating system are finished in the deterministic manner.... It is based on the priority of the task .....

@ rohitkhanna - In my view at least... it is nothing like immediately ( I mean you said "Real time" ) ..... The time dead lines in RTOS are fixed in some cases but it may get altered based on the priority of the task too in case by case and type of RTOS that you use ....

@ bigdog / rohitkhanna - Please correct the me if I am wrong with the explanation ?

with regards,

 

[kiranvarma3]

By using C or assembly you can perform one task at a time using infinite loop (while(1){}). but by using RTOS you can perform many tasks concurrently by using scheduling algorithms (ex:round robin scheduling). not only that RTOS provide built in library (no need to write code for basic task like serial communication etc.,), it provide resource management (CPU time, memory, etc.,). And many other advantages. for example if you design an LED screen application, in which our micro controller is trying to refresh the screen at 24frames/sec and at the same time the micro controller should read the animation data received via serial communication and stored the data in external memory, in such cases we need RTOS.

 

[sky_123]

@BigDog,

That is an excellent book!
I hope many people read it...

 

[rohitkhanna]

I will like to share one point here-

@ rohitkhanna - In my view at least... it is nothing like immediately ( I mean you said "Real time" ) ..... The time dead lines in RTOS are fixed in some cases but it may get altered based on the priority of the task too in case by case and type of RTOS that you use ....

@ bigdog / rohitkhanna - Please correct the me if I am wrong with the explanation ?

with regards,

It's not really necessary to comment on EVERYTHING milind. But if you do, then try and make it understandable by the level of person asking the question.