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FFT problem

Started by ivan...@hotmail.com August 18, 2008
Hi,

I am trying to call an FFT library function from assembly code. I am working with ADSP 21396 processor (SHARC). I picked _cfftn_nonSIMD. I've tried using the SIMD version but it doesn't work. Anyway, I don't have to use it since the FFT calculation is not under tight timing constraints.
The problem with the nonSIMD version is that it doesn't give correct results for 4096 points. _cfft128_nonSIMD, _cfft256_nonSIMD, _cfft512_nonSIMD, _cfft1024_nonSIMD and _cfft2048_nonSIMD all work, but _cfft4096_nonSIMD doesn't. It returns me garbage mostly -1.NAN. The size of input and output arrays should not be a problem, I've checked that. It has to be something related to the stack and memory and general, but I don't know what it could be. Anyone had a similar problem?

Cheers,
Ivan