bachi / libad9915

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src/ddsFreq.c 3.76 KB
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dfa91a3bc   pyb   libad9915 : add i... 
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  #include <stdlib.h>
  #include <stdio.h>
  #include <unistd.h>
  #include <math.h>
  #include "ddsFreq.h"
  #include "ad9915.h"
  
  //#define debug
  long double pgcd ( long double m , long double n)
  {
  	        if (fmod(m,n) ==0)
                  return n;
          return pgcd(n,fmod(m,n));
  }
  
  int setddsFreq(int fd, int f_dds, long double f0, long double fs)
  {
  
  	#ifdef debug
  		printf("f0=%Le\tfs=%Le
  ",f0,fs);
  	#endif
  
          if (fs<0 || f0<0) return EXIT_FAILURE;
  
  	struct frac f1;
  
  	f1.numerator = f0;
  	f1.denominator = fs;
  	
  	long double d1 = pgcd (f1.numerator , f1.denominator );
  	//printf(" d1 = %24.16Lf
  ",d1);
  
  	long double M = f0 / d1 ;
  	long double N = fs / d1 ;
  	//printf(" M = f0 / d1 = %24.16Lf
  ",M);
  	//printf(" N = fs / d1 = %24.16Lf
  ",N);
  
  
  	long double ftw = M * scalbn(1.0,32);
  	ftw /= N;
  	//printf("ftw = %24.16Lf
  ",ftw);
  
  	
  	//printf("X=floor(ftw) = %24.16Lf
  ",(long double)floor(ftw));
  	
  	long double Y = M * scalbn(1.0,32);
  	Y -=  N * floor(ftw);
  	//printf("Y=M*2**32-X*N = %24.16Lf
  ",Y);
  	
  	long double d2 = pgcd (Y,N);
  	//printf(" d2 = %24.16Lf
  ",d2);
  
  	long double A = Y / d2;
  	long double B = N / d2;
  	//printf("A = Y/d2 = %24.16Lf
  ",A);
  	//printf("B = N/d2 = %24.16Lf
  ",B);
  	
  	//printf("f0 = (M/N) * fclk= %24.32Lf
  ",fs*M/N);
  	//printf("f0 = (X+A/B)2**32= %24.32Lf
  ",fs*(floor(ftw)+A/B)/scalbn(1.0,32));
  	
  #ifdef debug
  printf("
   so finally the programmed registers are :
  "
          "ftw= 0x%08x         A= 0x%08x            B= 0x%08x
  "
          "",(unsigned int)ftw,(unsigned int)A,(unsigned int)B);
  printf("uint ftw = %d
  ",(unsigned int)ftw);
  
  printf("
   0x%08x 0x%08x 0x%08x 
  
  ",(unsigned int)ftw,(unsigned int)A,(unsigned int)B);
  //setFreqMM(fd,f_dds,(unsigned int)ftw, (unsigned int)A, (unsigned int)B);			
  #endif
  setFreqMM(fd,f_dds,(unsigned int)ftw, 2*(unsigned int)B, 2*(unsigned int)A);			//??why *2??
  	return EXIT_SUCCESS;
  }
  int ddsFreq(int fd, int f_dds)
  {
2146e89f7   bachi   ddsFreq.c : suppr... 
94
 
  	//checkSize();
dfa91a3bc   pyb   libad9915 : add i... 
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  	long double f0,fs;		
  	//printf("long = %lu
  ",sizeof (long));
  	//printf("float = %lu
  ",sizeof (float));
  	//printf("double = %lu
  ",sizeof (double));
  	//printf("long double = %lu
  ",sizeof (long double));
  
  	printf("
  Desired output Frequency (MHz) : ");	
  	scanf("%Lf",&f0);
  	printf("DDS frequency Clock (MHz) : ");
  	scanf("%Lf",&fs);
  
          //long double f0=atof(argv[1]); //desired output freq
          //long double fs=atof(argv[2]); //dds_clk
  	//int toto = (int)strtol(argv[3],NULL,0);
  	//printf("toto=%d\t%x
  ",toto,toto);
  
          if (fs<0 || f0<0) return EXIT_FAILURE;
  
  	struct frac f1;
  
  	f1.numerator = f0;
  	f1.denominator = fs;
  	
  	long double d1 = pgcd (f1.numerator , f1.denominator );
  	printf(" d1 = %24.16Lf
  ",d1);
  
  	long double M = f0 / d1 ;
  	long double N = fs / d1 ;
  	printf(" M = f0 / d1 = %24.16Lf
  ",M);
  	printf(" N = fs / d1 = %24.16Lf
  ",N);
  
  
  	long double ftw = M * scalbn(1.0,32);
  	ftw /= N;
  	printf("ftw = %24.16Lf
  ",ftw);
  
  	
  	printf("X=floor(ftw) = %24.16Lf
  ",(long double)floor(ftw));
  	
  	long double Y = M * scalbn(1.0,32);
  	Y -=  N * floor(ftw);
  	printf("Y=M*2**32-X*N = %24.16Lf
  ",Y);
  	
  	long double d2 = pgcd (Y,N);
  	printf(" d2 = %24.16Lf
  ",d2);
  
  	long double A = Y / d2;
  	long double B = N / d2;
  	printf("A = Y/d2 = %24.16Lf
  ",A);
  	printf("B = N/d2 = %24.16Lf
  ",B);
  	
  	printf("f0 = (M/N) * fclk= %24.32Lf
  ",fs*M/N);
  	printf("f0 = (X+A/B)2**32= %24.32Lf
  ",fs*(floor(ftw)+A/B)/scalbn(1.0,32));
  	
  printf("
   so finally the programmed registers are :
  "
          "ftw= 0x%08x         A= 0x%08x            B= 0x%08x
  "
          "",(unsigned int)ftw,(unsigned int)A,(unsigned int)B);
  //printf("uint ftw = %d
  ",(unsigned int)ftw);
  
  printf("
   0x%08x 0x%08x 0x%08x 
  
  ",(unsigned int)ftw,(unsigned int)A,(unsigned int)B);
  //setFreqMM(fd,f_dds,(unsigned int)ftw, (unsigned int)A, (unsigned int)B);			
  setFreqMM(fd,f_dds,(unsigned int)ftw, 2*(unsigned int)B, 2*(unsigned int)A);			
  	return EXIT_SUCCESS;
  }