Problem with interrupts on ADSP-21161N

Hi Jim,

Jim Thomas wrote:

> My guess is that the problem occurs when the higher priority
interrupt
> pre-empts to lower priority one.  This is more likely to happen at
> higher rates.  Can you turn off the NESTM bit?

I was waiting for your contribution. It definitely seems to be a
problem with timing... When the SPORT interrupt was running at 240 Hz I
didn't have that problem.

Will try to disable interrupt nesting (which worked in a great manner
for SPORT0 interrupt at 240 Hz), and will see what happens.
Thanks for your time,

JaaC

Hi,

I apologize for posting the same, several times. This is because of the new
beta service from google groups. Sometimes it fails to confirm that the
message was succesfully sent.

Regards,

--
Jaime Andr�s Aranguren Cardona
jaac@nospam.sanjaac.com
SanJaaC Electronics
Soluciones en DSP
www.sanjaac.com

(Remove "nospam" from e-mail address)

"Jaime Andr&#4294967295;s Aranguren Cardona" <jaime.aranguren@gmail.com> escribi&#4294967295; en el
mensaje news:1106759966.692019.47020@f14g2000cwb.googlegroups.com...
> Hi Jim,
>
> Jim Thomas wrote:
>
> > My guess is that the problem occurs when the higher priority
> interrupt
> > pre-empts to lower priority one.  This is more likely to happen at
> > higher rates.  Can you turn off the NESTM bit?
>
> I was waiting for your contribution. It definitely seems to be a
> problem with timing... When the SPORT interrupt was running at 240 Hz I
> didn't have that problem.
>
> Will try to disable interrupt nesting (which worked in a great manner
> for SPORT0 interrupt at 240 Hz), and will see what happens.
> Thanks for your time,
>
> JaaC
>

Hello,

I've got some news, guys.

Nesting was not the problem.
Stack overflow was not the problem.
ADI libraries for ISR management were not the problem.

This was the problem, my stupid mistake:

In my code, I have routines like this, running on the ISR (at least one of
them):

buffer[counter] = sample;        // Store sample in buffer
counter++;                       // Increment counter
if (counter == MAX_VALUE) {
  flag = true;                   // Set flag if buffer gets full
}
else {
  flag = false;                  // Otherwise, keep it cleared
}

My mistake was that I forgot the "counter = 0;" sentence near "flag = true".
I was doing it in another routine, which does not get triggered at this
point, but in a subsequent call to a function, the calling is controlled by
the "flag".

I simply moved the "counter = 0;" sentence near "flag = true", and
everything works perfectly. Even with interrupt nesting enabled!!

I want to thank all of you for taking your precious time to give me your
valuable advice.

Long live comp.dsp!!

--
Jaime Andr�s Aranguren Cardona
jaac@nospam.sanjaac.com
SanJaaC Electronics
Soluciones en DSP
www.sanjaac.com

(Remove "nospam" from e-mail address)

"Jim Thomas" <jthomas@bittware.com> escribi&#4294967295; en el mensaje
news:10vfc75plgteu2e@corp.supernews.com...
> Jerry Avins wrote:
> > Jaime Andr&#4294967295;s Aranguren Cardona wrote:
> >>I placed a hardware breakpoint in the range from 0x50000 to 0x50005 to
> >>halt the processor whenever memory in this range is written. The
> >>interrupt stopped to occur before the stack was full, so th problem is
> >>not being caused by stack overflow, at least not directly. The problem
> >>is that the IMASK register, which masks the enabled interrupts, is
> >>being written with data that disables my interrupts, so they don't
> >>occur anymore.... All of this modifications happens inside the code
> >>which is provided on libraries by ADI.
> >
> >
> > My point may yet shed light. Run time is longer at lower interrupt
> > rates. What about the number of interrupts? Do they increase?
> >
>
> My guess is that the problem occurs when the higher priority interrupt
> pre-empts to lower priority one.  This is more likely to happen at
> higher rates.  Can you turn off the NESTM bit?
>
> --
> Jim Thomas            Principal Applications Engineer  Bittware, Inc
> jthomas@bittware.com  http://www.bittware.com    (603) 226-0404 x536
> Quidquid latine dictum sit, altum sonatur.
> Whatever is said in Latin sounds profound.