help reqd rgd example preempt pls(with denx core)

Wolfgang Grandegger wolfgang.grandegger at
Tue Oct 5 22:04:21 CEST 2004

On 10/01/2004 09:39 AM deepa.vijayaraghavan at wrote:
> hi all,
> there were a few mistakes, as the earlier mail was typed in a hurry..
> sorry abt that.
> I am referring to the example preempt, that demonstrates how a higher
> priority task and a lower priority task work together. My application is
> also sort of similar, hence clarity on this example will help me a great
> deal.
> I am using IBM ppc 440 based ebony board.
> In the functions rt_task_make_periodic(), if the second parameter is
> left as it is(now + tick_period), I get no output. Infact when I check
> if the task gets scheduled at all, by using rt_printk statements, I get
> no output.
> But if I set the delay to 0(or some small number), I get output so long
> as the init_module() runs. I get output based on the number of times the
> tasks get scheduled before the init_module() function is completed. I
> use 'insmod' for the loading the module.
> When I do rmmod, the tasks are terminated without errors.
> The same is the case with the 'Frank' example too.
> I use the 'One shot' timer. With 'periodic' timer, i see no output
> whatsoever.
> Any help is highly appreciated.

Can you please provide more information on the problems and errors. What
version of RTAI are you using? Can we have a look to a test module
demostrating the problem?


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