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uc/OS v/s freeRTOS

Posted by Nobody/Anonymous on November 10, 2004
how do we compare uc/OS with freeRTOS. I am interested only in reliability and performance. ie how good is the existing features of freeRTOS compared to the similar features offered by uc/OS

RE: uc/OS v/s freeRTOS

Posted by Richard on November 11, 2004
Which is best depends on your application. The mechanics of using FreeRTOS and uCOS are very similar.

There are two main differences between the two:

1)Licensing. FreeRTOS is completely free for any application. The uCOS source code comes bundled with a book requiring purchase, and a binary run time license ($$$) is required if you use uCOS in a commercial application.

2)Scheduling. uCOS uses a bitmap scheduler, FreeRTOS does not. A bitmap scheduler has the advantage of allowing a more deterministic context switch time, and in some cases a faster context switch time – it does however severely restrict your design freedom as it only allows a single task at any given priority level. FreeRTOS on the other hand is more flexible as any number of tasks can share the same priority.

I think FreeRTOS is simpler to use; initialization is automatic on creation of the first task, and ISR routines don’t have to be written in assembler. But you are probably asking the wrong person if you want a non-biased opinion!


RE: uc/OS v/s freeRTOS

Posted by Nobody/Anonymous on December 2, 2004
another point is ports: ucos supports tens (hundreds) of MCUs while freertos is still starting up. also code quality has been proven by validation suites for ucos (e.g. FDA).

I wonder how well freertos covers a full range testsuite..?

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