main.c

TigerSharc TS201 32-bit floating point FFT routine

// Example C usage of fft16

#include <stdio.h>
#include <sysreg.h>
#include <builtins.h>
#include <math.h>
#include "FFTDef.h"
#include <filter.h>

#define pi 3.1415926

section ("input")
#if N==64
 int input[N] = {
                  #include "inputs/input64.dat"
                  };
#elif N==128
 int input[N] = {
                  #include "inputs/input128.dat"
                  };
#elif N==256
 int input[N] = {
                  #include "inputs/input256.dat"
                  };
#elif N==512
 int input[N] = {
                  #include "inputs/input512.dat"
                  };
#elif N==1024
 int input[N] = {
                  #include "inputs/input1024.dat"
                  };
#elif N==2048
 int input[N] = {
                  #include "inputs/input2048.dat"
                  };
#elif N==4096
 int input[N] = {
                  #include "inputs/input4096.dat"
                  };
#elif N==8192
 int input[N] = {
                  #include "inputs/input8192.dat"
                  };
#elif N==16384
 int input[N] = {
                  #include "inputs/input16384.dat"
                  };
#elif N==32768
 int input[N] = {
                  #include "inputs/input32768.dat"
                  };
#endif
#ifdef initialization_error
      int input[N];
#endif


#pragma align 4
section ("int_buff") int
	int_buff[N];

volatile int
	tmp_i0,
	tmp_i1;
	
float twiddle_table[1024]={
                  #include "inputs/twiddle_1024.dat"
                  };

complex_float  twiddle[512] = {
                  #include "inputs/twiddle_1024.dat"
                  };
                  	


//*********************************** main ********************************************
void main( void )
{
	int index;
/*in the case of TS201, at the beginning of the program the
cache must be enabled. The procedure is contained in the
cache_enable macro that uses the refresh rate as input parameter
      -if CCLK=500MHz, refresh_rate=750
      -if CCLK=400MHz, refresh_rate=600
      -if CCLK=300MHz, refresh_rate=450
      -if CCLK=250MHz, refresh_rate=375
*/
#ifdef __ADSPTS201__
  asm("#include <defts201.h>");
  asm("#include <cache_macros.h>" );
  asm("cache_enable(750);");
  asm("#include <ini_cache.h>");
  asm("#include <fftdef.h>");
  asm("preload_cache;");

#endif

#ifdef initialization_error

  printf("ERROR: This FFT function works only in the following conditions:\n");
  printf("N must be a power of 2 and 64<=N<=32768\n");
  printf("Please change the settings in the file FFTDef.h\n");
#else
	tmp_i0 = __builtin_sysreg_read( __CCNT0 );         // read initial cycle count
    /*
	for(index=0;index<512;index++)
	{
		twiddle_table[2*index]=cos(2*pi*index/1024);
		twiddle_table[2*index+1]=sin(2*pi*index/1024);
	}
    */
	FFT16(&(input), &(int_buff), N, log2_N);



	tmp_i1 = __builtin_sysreg_read( __CCNT0 );         // read final cycle count
//Atention! This cycle count includes also the code used to push and pop r24:31 
//at the beginning and at the end of the fft routine (totally 51 cycles)
	printf("cycle count = %d\n", tmp_i1 - tmp_i0);       // print the cycle count

#endif
}