Hello,
I want to use the FFT algorithm from C67xDSPLIB library. I work on DSP core of OMAP-L137 processor.
I chose function: void DSPF_sp_cfftr2_dit (float * x, float * w, short n),
where:
x - pointer to complex data input.
w - Pointer to complex twiddle factor in bit-reverse order.
n - Length of FFT in complex samples, power of 2 such that n ≥32 and n<=32K.
SPRU657.pdf says how to use it:
void main(void)
{
gen_w_r2(w, N); // Generate coefficient table
bit_rev(w, N>>1); // Bit−reverse coefficient table
DSPF_sp_cfftr2_dit(x, w, N);
// input in normal order, output in
// order bit−reversed
// coefficient table in bit−reversed
// order
}
But how to prepare the x and w. What mathematical operations (functions) should be used.
I have samples from an ADC converter and what must I do to replace them to vectors x and w?
