sam2_2.c

本文件是ni公司的labwindows/cvi软件的部分例子和源程序

#include <ansi_c.h>
#define PI  3.1415926  
//wave data generation function
void GenerateWave (int shape,double datapoints[100],double wavepeak)
{
    int i;
	double wavemax=wavepeak/2.0;
    switch (shape) {
        case 1 :        
        /* Sinewave */
            for (i=0;i<100;i++)
                datapoints[i] = wavemax * sin((((2.0*PI)/100.0) * i)) + 50.0;
            break;
        case 2 :       
        /* Square wave */
            for (i=0;i<33;i++)
                datapoints[i] = 50.0-wavemax;
            for (i=33;i<67;i++)
                datapoints[i] = 50.0+wavemax;
            for (i=67;i<100;i++)
                datapoints[i] = 50.0-wavemax;
            break;
        case 3 :       
        /* Triangle wave */
            for (i=0;i<25;i++) {
                datapoints[i] = i*4*wavepeak/100+50-wavemax;
                datapoints[i+25] = wavepeak - (i*4)*wavepeak/100+50-wavemax;
                datapoints[i+50] = i*4*wavepeak/100+50-wavemax;
                datapoints[i+75] = wavepeak - (i*4)*wavepeak/100+50-wavemax;
                }

            break;
        case 4 :       
        /* Random data */
            for (i=0;i<100;i++)
                datapoints[i] = rand()/32767.0 * wavepeak+50-wavemax;
            break;
        }
}