e018918b9287001d1262abe828d7ef4c

来自「基于ALTERA公司NIOSII的LED灯控PWM IP核设计」· 代码 · 共 32 行

#include "system.h"

typedef struct
{
    unsigned int divi;
    unsigned int duty;
    unsigned char enable;
}pwm_socket;
int main(void)
{
    int dir = 1;
    pwm_socket *pwm = PWM_0_BASE;
    pwm->divi = 1000;
    pwm->duty = 0;
    pwm->enable = 1;
    while(1){
        if(dir > 0){
            if(pwm->duty < pwm->divi)
                pwm->duty += 100;
            else
                dir = 0;
        }
        else{
            if(pwm->duty > 0)
                pwm->duty -= 100;
            else
                dir = 1;
        }
        printf("\b\b\b%3d",pwm->duty);
        usleep(100000);
    }
}