ISRs and rtems_task_wake_after

Joel Sherrill joel.sherrill at
Fri Feb 15 13:21:14 UTC 2002

"Aaron J. Grier" wrote:
> just a reality check.  I've been banging on the same chunk of code for
> two days straight now and I think I finally figured out what I was doing
> wrong.
> you cannot call rtems_task_wake_after from within an ISR, correct?

Correct.  task wake after is for tasks to delay.  ISRs are not tasks.
> IE "never never never block within an ISR" is a rule I should carve into
> the top of my monitor so I'm reminded of it every day, yes?

That's the 1st rule of embedded programming.  Quickly followed with
"don't take too long in an ISR" :)

> :)
> --
>   Aaron J. Grier  |   Frye Electronics, Tigard, OR   |  aaron at
>      "In a few thousand years people will be scratching their heads
>        wondering how on earth the first computer was invented and
>           bootstrapped without a prior computer to do it with."
>                     --  Chris Malcolm, on comp.arch

Joel Sherrill, Ph.D.             Director of Research & Development
joel at                 On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
   Support Available             (256) 722-9985

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