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Altera_Forum's avatar
Altera_Forum
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18 years ago

Example DSP Builder FFT megacore V7.1

Hi all,

I'm searching for a Simulink example of a application with the FFT megacore V7.1. My simulation still don't run after several hours of trying...

Thank you very much!

Reto

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    Reto,

    I found a few things:

    - the simulation wasnt long enough to see the results coming out. You had the simulation running for 600 clocks on a 1024 point FFT, you'll need at least 3X the FFT size to account for the latency.

    - the EOP and SOP packets were misformed. You should only assert for 1 clock and the SOP and EOP should be 1023 clocks away and then repeat every 1024 clocks.

    I've fixed the simulation and attached it. You'll need to regenerate the megacore of course.

    :)

    blk
  • Altera_Forum's avatar
    Altera_Forum
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    Thanks for the good demo design. Perhaps someone can help me.

    I'd like to alter the design to have SOP and EOP signals generated via DSP Builder - my input digital signal will stream continuously, and the FFT will pick off 2048 points (need SOP every 1024 for maximum packet size limitation, but need EOP at 2048 points)

    I am having difficulty mimicking the behavior of "Pulse Generator" with the available "Single Pulse" DSP Builder block.

    Thank you,

    --Mickey
  • Altera_Forum's avatar
    Altera_Forum
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    hello everyone,

    I am new about using this megafunction.

    I have video data from a sensor.

    and I have to do fft to this datas.

    I tried to do but is there anyone who can help me ?