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Wrong output with large size FFT

Question asked by hilbishnk on Dec 1, 2011
Latest reply on Dec 1, 2011 by Mitesh

I am pretty new to the SHARC processors and programing DSP's in general. I am trying to run a FFT of size 4098 and I am either not getting an output (seems to be stuck in the FFT function) or the wrong output. I have tried both "rfft" and a hand written fft function. I believe it is a memory problem. Even with smaller FFTs (2048 and 1024) if there are other large arrays in the program the output is inccorect. My FFT is fed into a neural network (severial large weight matrices), so im guessing its either a heap problem or stack problem.

 

My proccessor is a SHARC 21469.

Code attatched works for size 1024, but not 2048 or 4096. And when the large wieght matricies are added in it doesn't work for 1024.

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