#include <stdio.h>
#include <stdint.h>
#include <math.h>
#include <dsplib.h>

#define NUMSAMP 16
#define LENGTH NUMSAMP * 2
#define TAU 2 * 3.14159265358979323846

#pragma DATA_ALIGN(cosine, 8);
float cosine[LENGTH];

#pragma DATA_ALIGN(plot, 8);
int16_t plot[LENGTH];

#pragma DATA_ALIGN(fft, 8);
int16_t fft[LENGTH];

#pragma DATA_ALIGN(twiddle, 8);
int16_t twiddle[LENGTH];

#pragma DATA_ALIGN(itwiddle, 8);
int16_t itwiddle[LENGTH];

#pragma DATA_ALIGN(result, 8);
int16_t result[LENGTH];

void main(void)
{
 int i;
 int m = 0;
 float f0Tc = 0.25;

 for(i = 0; i<LENGTH; i = i+2)
 {
  cosine[i] = (float)cos(TAU * m * f0Tc);
  cosine[i+1] = (float)0.0;
  m++;
 }

 DSP_fltoq15(cosine, plot, (short)LENGTH);
 
 gen_twiddle_fft16x16(twiddle, (int)NUMSAMP);      
 gen_twiddle_ifft16x16(itwiddle, (int)NUMSAMP);    
                                                   
 DSP_fft16x16(twiddle, (int)NUMSAMP, plot, fft);  
                                                   
 DSP_ifft16x16(itwiddle, (int)NUMSAMP, fft, result);

}