On Thursday 12 March 2009 14:20:23 guoliang liu wrote:
> Hi all,
>
> I have a robot program running on Orocos, which has three component :
> Camera, SerialPort and WorkPart. The component WorkPart gets image from
> Camera and give command to robot by SerialPort. The WorkPart also need
> feedback data from SerialPort.
> But it just can work very well when I use ORO_SHECK_OTHERS. If I use
> ORO_SCHED_RT, the SerialPort can not feedback correctly. Maybe it becauses
> I give the wrong priority for three component.
> I gave the WorkPart highest priority and gave lower priority for Camera and
> SerialPort.
> If I run three component in the same time, does that mean the WorkPart will
> run all the time because it has highest priority and the others need to
> wait??
> I know a little about real time schedual, anyone can give a suggestion?

If you run a component with a NonPeriodicActivity and ORO_SCHED_RT and the
component runs in an 'infinite loop', it will prevent all the other components
to run with a lower priority. (99 is highest, 1 is lowest).

This issue is less with PeriodicActivity, because they go to sleep
periodically, which offers an opprotunity for the lower priority tasks to run.

Peter