extern void InitC5402(void);
extern void OpenMcBSP(void);
extern void CloseMcBSP(void);
extern void WRITEAD50(void);

  #include "math.h"
  #include "stdio.h"
  #define pi 3.1415927
  #define Length 102
  #define Len 8
 
  double x[Length],xc[Length],xr[Length];
  double vk[Len][Length],vs1[Len],vs2[Len],v[3],s[Len],z[Len];
  double vkn[Len][Length];
  double fr0,fr1,fr2,fr3,fc0,fc1,fc2,fc3,fs,fr,fc;
  double m1,m0,max1,max2;
  int i,j;
  
/***********************************************************************
** Main Function Program
***********************************************************************/
void main(void)
{           
      int inkey,outkeyrow,outkeycol;
      char outkey;
	  int *out = (int*)0x2b00;
	  int in[16] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
	  int ks;

	  fs = 8000;
  	  fr0 = 697.0;  fc0 = 1209.0;
  	  fr1 = 770.0;  fc1 = 1336.0;
  	  fr2 = 852.0;  fc2 = 1477.0;
  	  fr3 = 941.0;  fc3 = 1633.0;
  	  
  	  s[0] = fr0/fs;  s[4] = fc0/fs;
	  s[1] = fr1/fs;  s[5] = fc1/fs;
	  s[2] = fr2/fs;  s[6] = fc2/fs;
	  s[3] = fr3/fs;  s[7] = fc3/fs;
	  
/*input the key number from 0 to 15*/
	  InitC5402(); /* initialize C5402 DSP */
 	  OpenMcBSP();

	  for (;;)
	  {
	  	for (ks=0; ks<16; ks++)  
		{
		  inkey = in[ks];
	  	  if      (inkey==0)  {fr=fr3; fc=fc1;}
		  else if (inkey==1)  {fr=fr0; fc=fc0;}
		  else if (inkey==2)  {fr=fr0; fc=fc1;}
	      else if (inkey==3)  {fr=fr0; fc=fc2;}
	  	  else if (inkey==4)  {fr=fr1; fc=fc0;}
	      else if (inkey==5)  {fr=fr1; fc=fc1;}
	      else if (inkey==6)  {fr=fr1; fc=fc2;}
	      else if (inkey==7)  {fr=fr2; fc=fc0;}
	      else if (inkey==8)  {fr=fr2; fc=fc1;}
	      else if (inkey==9)  {fr=fr2; fc=fc2;}
	      else if (inkey==10) {fr=fr0; fc=fc3;}
	      else if (inkey==11) {fr=fr1; fc=fc3;}
	      else if (inkey==12) {fr=fr2; fc=fc3;}
	      else if (inkey==13) {fr=fr3; fc=fc3;}
	      else if (inkey==14) {fr=fr3; fc=fc0;}
	      else if (inkey==15) {fr=fr3; fc=fc2;}
	      
	      for (i=0; i<Length; i++)
	      {
	      	 xr[i] = sin(2*pi*fr*i/fs);
	  		 xc[i] = sin(2*pi*fc*i/fs);
	  		 x[i] = 1*(1.0*xc[i]+1.0*xr[i]);
	      }
          
          for (j=0; j<8; j++)
 	  	  {
		  	 for (i=0; i<Length; i++)
  		  	 {
	  		 	 *out = (int)(x[i]*16300.0);
	  			 WRITEAD50();  /* Tone output*/
	  	  	 }
	  	  }
		   
   		  for(i=0; i<Len; i++)
	  	  {
			v[2]=v[1]=v[0]=0;
			for (j=0; j<Length; j++)
			{
				v[2] = 2*(cos(2*pi*s[i]))*v[1]-v[0]+x[j];
				vk[i][j] = v[2];
				v[0] = v[1];
				v[1] = v[2];
			}	
	  	  }

	      for (i=0; i<Len; i++)
    	  {
			vs1[i] = vk[i][Length-1];
			vs2[i] = vk[i][Length-2];
	  	  }

		  for (i=0; i<Len; i++)
		  {
 	 		m1 = vk[i][Length-1] * vk[i][Length-1];
	  		m0 = vk[i][Length-2] * vk[i][Length-2];
	  		z[i] = m1+m0-2*cos(2*pi*s[i])*vk[i][Length-1]*vk[i][Length-2];
	  	  }
	  
	  	  max1=0.0;
	      
	  	  for (i=0; i<(Len/2); i++)
	  	  {
		  	if (z[i] >= max1) { max1 = z[i]; outkeyrow = i+1;}
	  	  }
	  
	  	  max2=0.0;
	      
		  for (i=4; i<Len; i++)
		  {
	  		if (z[i] >= max2) { max2 = z[i]; outkeycol = i-4+1;}
	  	  }
	  	  	 
/* Show the detceedt Key Number */ 
	  	  	 
	  	  if (outkeyrow==1)
	  	   	{
	  	   		if      (outkeycol==1) outkey = '1';
	  	   		else if (outkeycol==2) outkey = '2';
	  	   		else if (outkeycol==3) outkey = '3';
	  	   		else if (outkeycol==4) outkey = 'A';
	  	   	}
	  	  	 
	  	  else if (outkeyrow==2)
	  	   	{
	  	   		if      (outkeycol==1) outkey = '4';
	  	   		else if (outkeycol==2) outkey = '5';
	  	   		else if (outkeycol==3) outkey = '6';
	  	   		else if (outkeycol==4) outkey = 'B';
	  	   	}
	  	  	 
	  	  else if (outkeyrow==3)
	  	   	{
	  	   		if      (outkeycol==1) outkey = '7';
	  	   		else if (outkeycol==2) outkey = '8';
	  	   		else if (outkeycol==3) outkey = '9';
	  	   		else if (outkeycol==4) outkey = 'C';
	  	   	}
	  	  	 
	  	  else if (outkeyrow==4)
	  	   	{
	  	   		if      (outkeycol==1) outkey = '*';
	  	   		else if (outkeycol==2) outkey = '0';
	  	   		else if (outkeycol==3) outkey = '#';
	  	   		else if (outkeycol==4) outkey = 'D';
	  	   	}
	  	  	 
	  	  i=0;
	  	  i=0;
	    }
	  }
}
/***********************************************************************
** End of File –– exp015.c
***********************************************************************/