Dhana Sekar,

I guess you used the sine wave article from the below link,

http://www.pantechsolutions.net/dsp-dsc-boards/sine-wave-generation-using-tms320c6745-dsp

so i go ahead with the code explanation for this " SINE WAVE GENERATION USING TMS320C6745 DSP " article.

There are so many ways to generate the sine wave but in this article i used usual sine formula to generate the sine samples. Those sine samples only we seeing in the CCS Graph feature.

Explanation:

1. First assume the below factors to generate the sine samples and declare suitable datatype variables for the values.

Sampling Frequency in Hz = 1024000

Input Frequency in Hz = 4000

const float sampf = 1024000.0;// Sampling frquency is fixed

const int inpf = 4000; // change the input frquency from 1khz to 8khz(1000 to 8000)

float sampt;

double teta;

short value,*sinout;

int i,count,nsamp,value1;

2. Declaring a SDRAM memory location to store samples.

sinout = (short *)0xc0000000;

3. Formula for No.of.Sample,

No.of.Sample = ( Sampling Frequency in Hz / Input Frequency in Hz ) = (1024000/4000) = 256 Samples

Sampling Time in Sec = ( 1 / Sampling Frequency in Hz) = (1/1024000) = 0.0000009765625 Sec

sampt = 1/sampf;

nsamp = sampf/inpf;

4. Printf Statement to know the calculation values, it display the output in CCS console window.

Note: replace the single quote to double quote in all the printf statement

printf('\n Sampling Frequency is : %f',sampf);

printf('\n Sampling Time is :%f',sampt);

printf('\n Input Frequency is : %d',inpf);

printf('\n The number of Sample is : %d',nsamp);

5. Before write the samples to SDRAM , clearing the memory location

for(i=0;i<400;i++)

*(sinout+i)=0;

6. Formula for sine wave,

x(n) = Sin( 2 * pi * Input Frequency in Hz * Sampling Time in Sec * n)

where n is the nth sample

for(count=0;count<nsamp;count++)

{

teta = (2 * PI * inpf * sampt * count);

printf('\nteta = %lf',teta);

value = sin(teta)*1024;

printf('\t sin %lf Value is : %d',teta,value);

value1 = value&0x0000FFFF;

*sinout++ = value1;

}

7. Store the sine samples in DSP SDRAM memory location, so that we can view sine samples in CCS Graph window.

I clearly explained the coding , kindly let me know your status.