sinegen_table.c

教程《DSP 原理及其 C 编程开发技术》中的源代码

//Sinegen_table.c Generates a sinusoid for a look-up table 
 
#include <math.h>
#define table_size (short)10	 //set table size
short sine_table[table_size];	 //sine table array
short i;

interrupt void c_int11()	 //interrupt service routine
{
 output_sample(sine_table[i]); //output each sine value
 if (i < table_size - 1) ++i;  //incr index until end of table
    else i = 0;			 //reinit index if end of table
 return;				 //return from interrupt
}
 
void main()
{  
float pi=3.14159;

for(i = 0; i < table_size; i++)
  sine_table[i]=10000*sin(2.0*pi*i/table_size); //scaled values

i = 0;
comm_intr();                   //init DSK, codec, McBSP
while(1);                      //infinite loop
}