intout.c

来自「dsp AD公司ADSP21的代码,里面有FFT FIR IIR EQULIZE」· C语言 代码 · 共 55 行

#include <signal.h>
#include <math.h>
#include "rtdspc.h"

#define SIZE 10

int output_store[SIZE];
int in_inx = 0;
volatile int out_inx = 0;

void sendout(float x);
void output_isr(int ino);

int in_fifo[10000];
int index = 0;

void main()
{
    static float f,a;
    int i,j;

    for(i = 0 ; i < SIZE-1 ; i++) sendout(i);
    interrupt(SIG_IRQ3, output_isr);

    i = 0;
    j = 1;
    for(;;) {
        for(f=0.0 ; f < 1000.0 ; f += 0.005) {
            sendout(a*sinf(f*PI));
            i += j;
            if(i%25 == 0) {
                a = 100.0*exp(i*5e-5);
                if(a > 30000.0 || i < 0) j = -j;
            }
        }
    }
}
void sendout(float x)
{
    in_inx++;
    if(in_inx == SIZE) in_inx = 0;
    while(in_inx == out_inx);
    output_store[in_inx] = (int)x;
}
void output_isr(int ino)
{
    volatile int *out = (int *)0x40000002;

    if(index < 10000)
      in_fifo[index++]=16*in_inx+out_inx;

    *out = output_store[out_inx++] << 16;
    if(out_inx == SIZE) out_inx = 0;
}