Using KISS FFT with Ti's TMS320F2812 DSP

I am trying to use the KISS FFT library found on www.sourceforge.net
with the TMS320F2812 DSP from Texas Instruments.  After a bit of work,
I have been able to compile the code and even run a couple of
small-scale FFT calculations, but am having trouble with larger FFT
sizes.

I have a program set up to trigger the ADC periodically and commence
the FFT calculation after enough samples have been collected.  The
interrupt routine that runs whenever an ADC conversion completes
causes a light on the ezDSP board I'm using to toggle on and off, to
indicate that the processor is working.

When I run FFTs with small (less than 100) sample sizes, everything
works fine.  However, when I use sample sizes above this, the light no
longer blinks and the FFT calculation never seems to finish.

I have been looking through the source code for KISS FFT, but haven't
been able to find anything.

Does anyone have any suggestions?

-Brad

By default the watchdog will be enabled at startup.  When computing larger 
FFTs you probably don't have enough time to complete the processing before 
the watchdog resets the board.

Brad

"BradK" <b_kartchner@yahoo.com> wrote in message 
news:743175b4.0410111602.76069aa1@posting.google.com...
>I am trying to use the KISS FFT library found on www.sourceforge.net
> with the TMS320F2812 DSP from Texas Instruments.  After a bit of work,
> I have been able to compile the code and even run a couple of
> small-scale FFT calculations, but am having trouble with larger FFT
> sizes.
>
> I have a program set up to trigger the ADC periodically and commence
> the FFT calculation after enough samples have been collected.  The
> interrupt routine that runs whenever an ADC conversion completes
> causes a light on the ezDSP board I'm using to toggle on and off, to
> indicate that the processor is working.
>
> When I run FFTs with small (less than 100) sample sizes, everything
> works fine.  However, when I use sample sizes above this, the light no
> longer blinks and the FFT calculation never seems to finish.
>
> I have been looking through the source code for KISS FFT, but haven't
> been able to find anything.
>
> Does anyone have any suggestions?
>
> -Brad 

Thanks for the suggestion.  I hadn't thought about the watchdog, but
it turns out that is was disabled anyway.  I discovered that the
problem was that I didn't have enough memory on or off the chip to
store the FFT samples and results (If I had only checked the value
returned by the far_malloc function...).  So, I'll be adding more
memory.

Thanks for the reply!

-Brad


"Brad Griffis" <bradgriffis@hotmail.com> wrote in message news:<mkGad.8749$Rf1.8204@newssvr19.news.prodigy.com>...
> By default the watchdog will be enabled at startup.  When computing larger 
> FFTs you probably don't have enough time to complete the processing before 
> the watchdog resets the board.
> 
> Brad
> 
> "BradK" <b_kartchner@yahoo.com> wrote in message 
> news:743175b4.0410111602.76069aa1@posting.google.com...
> >I am trying to use the KISS FFT library found on www.sourceforge.net
> > with the TMS320F2812 DSP from Texas Instruments.  After a bit of work,
> > I have been able to compile the code and even run a couple of
> > small-scale FFT calculations, but am having trouble with larger FFT
> > sizes.
> >
> > I have a program set up to trigger the ADC periodically and commence
> > the FFT calculation after enough samples have been collected.  The
> > interrupt routine that runs whenever an ADC conversion completes
> > causes a light on the ezDSP board I'm using to toggle on and off, to
> > indicate that the processor is working.
> >
> > When I run FFTs with small (less than 100) sample sizes, everything
> > works fine.  However, when I use sample sizes above this, the light no
> > longer blinks and the FFT calculation never seems to finish.
> >
> > I have been looking through the source code for KISS FFT, but haven't
> > been able to find anything.
> >
> > Does anyone have any suggestions?
> >
> > -Brad