写的一个MINI2440用其BUTTON 控制其 LED灯的软件

不是用的GPBDAT做的  这个通过改变寄存器来控制LED暂时还没搞懂  我这个是直接通过读取后台的BUTTON值来控制LED灯的

都是在2.6.29.4上编译的

 

#include <stdio.h>#include <stdlib.h>#include <unistd.h>#include <sys/ioctl.h>#include <sys/types.h>#include <sys/stat.h>#include <fcntl.h>#include <sys/select.h>#include <sys/time.h>#include <errno.h>#define led_on 1#define led_off 0int main(void){int i;int buttons_fd;char key_value[6];buttons_fd = open("/dev/buttons", 0);if (buttons_fd < 0) {perror("open device buttons");exit(1);}int led_fd; struct file *a; led_fd=open("/dev/leds",O_RDWR); if(led_fd==-1) printf("open_leds error");void led_off_all(void) { int a; for( a=0;a<4;a++) ioctl(led_fd,led_off,a); }for (;;) {fd_set rds;int ret;FD_ZERO(&rds);FD_SET(buttons_fd, &rds);ret = select(buttons_fd + 1, &rds, NULL, NULL, NULL);if (ret < 0) { perror("select");exit(1);}if (ret == 0) {printf("Timeout./n");} else if (FD_ISSET(buttons_fd, &rds)) {int ret = read(buttons_fd, key_value, sizeof key_value);if (ret != sizeof key_value) {if (errno != EAGAIN)perror("read buttons/n");continue;} else { led_off_all();for (i = 0; i < 5; i++) { int a=key_value[i]; if(a==49) //button 按下后从控制台显示的十进制是49 { printf("key%d is press && led%d is lighting/n",i,i); ioctl(led_fd,led_on,i); }}}}}close(buttons_fd); close(led_fd);}