RV: Timer service routines

[fernando.ruiz at ctv.es]

-----Mensaje original-----
De: fernando.ruiz at ctv.es [mailto:fernando.ruiz at ctv.es]
Enviado el: sabado, 18 de noviembre de 2000 22:06
Para: Jake Janovetz
Asunto: RE: Timer service routines


Here, the documentation

http://www.oarcorp.com/rtems/betas/rtems-4.5.0-beta/online-docs/rtemsdoc-4.5
-beta3/share/rtemsdoc/html/c_user/c_user00112.html

about of timers. This is the online doc. But you can get the PDF (very good
doc)
from ftp.oarcorp.com.

The timer has the same HARDWARE priority that the system clock.
No task priority. It runs always. The best place for Watchdog or similar.
It is the system clock the caller. Not scheduled (I think..).
The same look that isr. Async by periodic (fired after period) clock.

None isr or timer service must take a lot of time. You can signal a waited
task
and the signaled task makes the slow work. Ever the same philosophy.

(Help Joel if I lie... but my programs runs... very good)

All the interrupt catched are a good place to exec the RTEMS directives.

My kbd_isr() send an kbd_event to waited wait_kbd() routine
and it runs very good. There the code calls RTEMS directives.

The same method in the timer service routine.

What kind of code need you run?

Need you a bref example that runs without problems?

Ahh if the docs includes the easy call directives examples our
life will be wonderful...

Saludos.->From Spain :)

Fernando RUIZ CASAS
fernando.ruiz at ctv.es

P.D.:
Is Snapshot list the best place to ask the kind of question?
I don't know well because I am new is RTEMS.
I think that rtems-users is best place. Isn't it?

-----Mensaje original-----
De: Jake Janovetz [mailto:janovetz at uiuc.edu]
Enviado el: sabado, 18 de noviembre de 2000 19:47
Para: rtems-snapshots at oarcorp.com
Asunto: Timer service routines


Hello...

   I believe this has been asked before, but I cannot find it in
the past archives...  I need a bit more information on the
execution of timer service routines.  What context do they run
in and with what priority?  Are they expected to finish very
quickly (like interrupt service routines)?
   Basically, I'm wondering if the TSR itself can execute some
code, then reset the timer or if I should write it such that
it sends a message to another thread to perform the execution.

    Jake