AnsweredAssumed Answered

FFT accelerator input buffer for real data

Question asked by ChristianH on Feb 26, 2015
Latest reply on Aug 26, 2015 by ChristianH



I've searched through several threads and manuals but did not find an answer so far.


I'd like to use the SHARC ADSP-21469 FFT accelerator for real input data (imaginary part is zero).

The FFT is done each second on the incoming audio data stream with 256 samples (so one shot FFT, no repeat).


I'm thinking of saving the transfer time and memory space for just zeros in the imaginary part.

Do I need to transfer / clear the imaginary input buffer part each time I want to start a new FFT?

In other words is the input buffer of the FFT accelerator overwritten when starting the FFT or is it hold (until power cycle)?