How will RTOS react when task preemption and interrupt occur?

hi,

I got confused how the RTOS will react when the task preemption is occured
and any one of the interrupt is occured , i donot know even my question
is correct or not.

Thanks
G kannan

Re: RTOS doubt

If the interrupt is opened, OS should process the interrupt. But if the task processing the interrupt is low priority, OS could transfer control to the task.

Re: RTOS doubt

it might vary with the type of RTOS you are using . most of them sport different scheduling algorithms........
-F

Re: RTOS doubt

actually my question is , The lower priority task is running at that time
one higher priority task is coming and one externaal interrupt also coming
what will happend ?

Thanks

Re: RTOS doubt

i ll explain in other way
for preemptive kernel if ISR occurs the Lowest priority task save its contents and move on to work then when the ISR is complete doing the sheduler will check for the task of the priorities and jump to highest priority task the as it goes
as in ucos is an preemptive RTOS

Re: RTOS doubt

well if the task which is comming has higher prioprity then the one running the (in Preemptive Scheduler ) it will save the context of the running task and and run the task with higher priority and also for the interrupt the ISR will/can spawn the task to service the Interrupt this new task will be ready to run but not untill all higher priority task has executed

regards
I guess I explained

Added after 26 seconds:

well if the task which is comming has higher prioprity then the one running the (in Preemptive Scheduler ) it will save the context of the running task and and run the task with higher priority and also for the interrupt the ISR will/can spawn the task to service the Interrupt this new task will be ready to run but not untill all higher priority task has executed

regards
I guess I explained

guys in which software or tool this task preemption have to work.. will u plz say... jmahesh_17@yahoo.co.in

Pre emption has to work on RTOS or even general purpose systems.. in rtos, it can be done by Vxworks tool...