Threads/Fibers code?

[jonr]

I have an application that is in need of "fibers"  (see: http://en.wikipedia.org/wiki/Fiber_(computer_science) ).  Basically, non-preemptive threads where a process can allow another process to run by calling "yield()".  At a low level, the scheduler round robins among tasks with each task having its own stack.   Is there any simple existing code for this out there?

[jonr · Accepted solution]

I ended up using CocoOS.  Works great, especially after I wrote a thread to do round robin scheduling of the other threads.

[jonr]

I got FreeRTOS to compile and link OK, but it doesn't actually seem to run threads.  So if anyone has it working on MPC5444 or MPC 5634, pleae let me know.

  #.section ".xcptn","ax"    # The "ax" is required to generate"non-text" code  */  .section .__exception_handlers,text  .align  16

[jonr]

FreeRTOS would also work.  Does anyone have it running with CodeWarrior on a MPC5xxx?