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Altera_Forum
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17 years ago

Help with altera FFT

hello; what i want to do is to get spectrum of an sinusoidal signal using the altera fft core i have generated a v8 fft with the following setting: fft point : 64 (to start with) archi...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
17 years ago

I changed the FFT to a 256-point burst architecture with the inputs coming from a ROM. When the ROM content is from a digitized 1000Hz analog sine wave, I get two peaks with sidelobes (is that what you call them?). However, when I change the ROM data to numbers generated by the equation

ROM_data = sin(2*1000*pi*[0:255]/256)

The FFT output is all zeros, and even the exponent is all zeros. What happened?