How to setup a mic while implementing DTMF detection in DSK6713

Hi Abdallah,

Which sample code you are trying with?
Is it TI provided example code or your own developed code?
If it is TI example code then details with me, so that i can help you out in better way.

Code taken from chapter 10 of Rulph Chassaing's book.

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//DTMF.c (Partial)Decodes DTMF signals and turn on corresponding LEDs
#define N 100
short i; short buffer[N];
short sin697[N],cos697[N],sin770[N],cos770[N],sin852[N],cos852[N],sin941[N],cos941[N],sin1209[N],cos1209[N],sin1336[N],cos1336[N],sin1477[N],cos1477[N];
long weight697,weight697_sin,weight697_cos,weight770,wight770_sin,weight770_cos,weight852,weight852_sin,weight852_cos;
long weight941,wight941_sin,weight941_cos,weight1209,wight1209_sin,weight1209_cos,weight1336,wight1336_sin,weight1336_cos;
long wight1477,weight1477_sin,weight1477_cos;
long weight1,weight2,choice1,choice2;

interrupt void c_int11()

{
for (i = N-1; i > 0; i--)
buffer[i]=buffer[i-1]; // initialize buffer
buffer[0]=input_sample(); //input sample into buffer
output_sample(buffer[0]*10); //output
weight697_sin=0; weight697_cos=0; //sine/cosine weight @ each freq
weight770_sin=0; weight770_cos=0;
weight852_sin=0; weight852_cos=0;
weight941_sin=0; weight941_cos=0;
weight1209_sin=0; weight1209_cos=0;
weight1336_sin=0; weight1336_cos=0;
weight1477_sin=0; weight1477_cos=0;


for (i = 0; i < N; i++)
{
weight697_sin = weight697_sin +buffer[i] * sin697[i];
weight697_cos=weight697_cos+buffer[i]*cos697[i];
weight770_sin=weight770_sin+buffer[i]*sin770[i];
weight770_cos=weight770_cos+buffer[i]*cos770[i];
weight852_sin=weight852_sin+buffer[i]*sin852[i];
weight852_cos=weight852_cos+buffer[i]*cos852[i];
weight941_sin=weight941_sin+buffer[i]*sin941[i];
weight941_cos=weight941_cos+buffer[i]*cos941[i];
weight1209_sin=weight1209_sin+buffer[i]*sin1209[i];
weight1209_cos=weight1209_cos+buffer[i]*cos1209[i];
weight1336_sin=weight1336_sin+buffer[i]*sin1336[i];
weight1336_cos=weight1336_cos+buffer[i]*cos1336[i];
weight1477_sin=weight1477_sin+buffer[i]*sin1477[i];
weight1477_cos=weight1477_cos+buffer[i]*cos1477[i];
}
//for each freq compare sine weight and cosine weight and choose largest
if(abs(weight697_sin)>abs(weight697_cos)) {weight697=abs(weight697_sin);}
else {weight697=abs(weight697_cos);}
if(abs(weight770_sin)>abs(weight770_cos)) {weight770=abs(weight770_sin);}
else {weight770=abs(weight770_cos);}
if(abs(weight852_sin)>abs(weight852_cos)) {weight852=abs(weight852_sin);}
else {weight852=abs(weight852_cos);}
if(abs(weight941_sin)>abs(weight941_cos)) {weight941=abs(weight941_sin);}
else {weight941=abs(weight941_cos);}
if(abs(weight1209_sin)>abs(weight1209_cos)) {weight1209=abs(weight1209_sin);}
else {weight1209=abs(weight1209_cos);}
if(abs(weight1336_sin)>abs(weight1336_cos)) {weight1336=abs(weight1336_sin);}
else {weight1336=abs(weight1336_cos);}
if(abs(weight1477_sin)>abs(weight1477_cos)) {weight1477=abs(weight1477_sin);}
else {weight1477=abs(weight1477_cos);}

weight1=weight697; choice1=1;//among weight697,... weight941 find largest
if(weight770>weight1) {weight1=weight770; choice1=2;} //...
if(weight852>weight1) {weight1=weight852; choice1=3;}
if(weight941>weight1) {weight1=weight941; choice1=4;}
weight2=weight1209; choice2=1;//among weight1209,...weight1477 find largest
if(weight1336>weight2) {weight2=weight1336; choice2=2;}
if(weight1477>weight2) {weight2=weight1477; choice2=3;}
if((weight1>40000)&&(weight2>40000)) //set a threshhold
{ // depending on choices1 and 2 turn on corresponding LEDs
if((choice1==1)&&(choice2==1)) //button "1" -> 0001
{DSK6713_LED_off(0);DSK6713_LED_off(1);DSK6713_LED_off(2);DSK6713_LED_on(3);}
if((choice1==1)&&(choice2==2)) //button "2" -> 0010
{DSK6713_LED_off(0);DSK6713_LED_off(1);DSK6713_LED_on(2);DSK6713_LED_off(3);}
if((choice1==1)&&(choice2==3)) //button "3" -> 0011
{DSK6713_LED_off(0);DSK6713_LED_off(1);DSK6713_LED_on(2);DSK6713_LED_on(3);}
if((choice1==2)&&(choice2==1)) //button "4" -> 0100
{DSK6713_LED_off(0);DSK6713_LED_on(1);DSK6713_LED_off(2);DSK6713_LED_off(3);}
if((choice1==2)&&(choice2==2)) //button "5" -> 0101
{DSK6713_LED_off(0);DSK6713_LED_on(1);DSK6713_LED_off(2);DSK6713_LED_on(3);}
if((choice1==2)&&(choice2==3)) //button "6" -> 0110
{DSK6713_LED_off(0);DSK6713_LED_on(1);DSK6713_LED_on(2);DSK6713_LED_off(3);}
if((choice1==3)&&(choice2==1)) //button "7" -> 0111
{DSK6713_LED_off(0);DSK6713_LED_on(1);DSK6713_LED_on(2);DSK6713_LED_on(3);}
if((choice1==3)&&(choice2==2)) //button "8" -> 1000
{DSK6713_LED_on(0);DSK6713_LED_off(1);DSK6713_LED_off(2);DSK6713_LED_off(3);}
if((choice1==3)&&(choice2==3)) //button "9" -> 1001
{DSK6713_LED_on(0);DSK6713_LED_off(1);DSK6713_LED_off(2);DSK6713_LED_on(3);}
if((choice1==4)&&(choice2==1)) //button "*" -> 1010
{DSK6713_LED_on(0);DSK6713_LED_off(1);DSK6713_LED_on(2);DSK6713_LED_off(3);}
if((choice1==4)&&(choice2==2)) //button "0" -> 1011
{DSK6713_LED_on(0);DSK6713_LED_off(1);DSK6713_LED_on(2);DSK6713_LED_on(3);}
if((choice1==4)&&(choice2==3)) //button "#" -> 1100
{DSK6713_LED_on(0);DSK6713_LED_on(1);DSK6713_LED_off(2);DSK6713_LED_off(3);}
}
else { //weights below threshold, turn LEDs off
DSK6713_LED_off(0);DSK6713_LED_off(1);DSK6713_LED_off(2);DSK6713_LED_off(3);
}
return;
}
void main()
{
DSK6713_LED_init();
DSK6713_LED_off(0);DSK6713_LED_off(1);DSK6713_LED_off(2);DSK6713_LED_off(3);
for (i = 0; i < N; i++) //define sine/cosine for all 7 frequencies
{
buffer[i]=0;
sin697[i]=1000*sin(2*3.14159*i/8000.*697);
cos697[i]=1000*cos(2*3.14159*i/8000.*697);
sin770[i]=1000*sin(2*3.14159*i/8000.*770);
cos770[i]=1000*cos(2*3.14159*i/8000.*770);
sin852[i]=1000*sin(2*3.14159*i/8000.*852);
cos852[i]=1000*cos(2*3.14159*i/8000.*852);
sin941[i]=1000*sin(2*3.14159*i/8000.*941);
cos941[i]=1000*cos(2*3.14159*i/8000.*941);
sin1209[i]=1000*sin(2*3.14159*i/8000.*1209);
cos1209[i]=1000*cos(2*3.14159*i/8000.*1209);
sin1336[i]=1000*sin(2*3.14159*i/8000.*1336);
cos1336[i]=1000*cos(2*3.14159*i/8000.*1336);
sin1477[i]=1000*sin(2*3.14159*i/8000.*1477);
cos1477[i]=1000*cos(2*3.14159*i/8000.*1477);
}
comm_intr(); while(1); //init DSK, codec, McBSP; infinite loop
}

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