按键驱动测试程序

来源：互联网发布：图像算法工程师待遇编辑：程序博客网时间：2024/05/16 11:42

宝剑锋从磨砺出，梅花香自苦寒来。——《警世贤文》

上一篇分析了一波驱动程序的代码，虽然有一些部分还是不懂，但还是挤出来一个测试程序，不足之处，请各位告知：

#include <stdio.h>#include <stdlib.h>#include <sys/ioctl.h>#include <fcntl.h>#include <unistd.h>#define KEY1 0x01#define KEY2 0x02#define KEY3 0x04#define KEY4 0x08#define PLATDRV_MAGIC   0x60#define OFF _IO (PLATDRV_MAGIC,0x18)#define ON _IO (PLATDRV_MAGIC,0X19)int main (int argc, char **argv){    int button_fd;    int led_fd;    int ret_button;    int current_button;int i;int j;int x;int y;        button_fd = open("/dev/button",0);    if(button_fd<0)    {        printf("open button failed.\n");        exit(1);    }while(1)    {        ret_button = read(button_fd,¤t_button,sizeof(4));        if(ret_button != sizeof(current_button))        {            printf("Read() button failed.\n");        }else{    if (current_button == KEY1){           led_fd = open("/dev/led0",O_RDWR,755);switch(i%2)                  {                  case 0:                       ioctl(led_fd,OFF,0);                      i++;                    printf("Turn led0 OFF.\n");                    break;                  case 1:                       ioctl(led_fd,ON,0);                      i++;                    printf("Turn led0 ON.\n");                     break;}}else if (current_button == KEY2){    led_fd = open("/dev/led1",O_RDWR,755);    switch(j%2)                  {                  case 0:                       ioctl(led_fd,OFF,1);                      j++;                    printf("Turn led1 OFF.\n");                    break;                  case 1:                       ioctl(led_fd,ON,1);                      j++;                    printf("Turn led1 ON.\n");                    break;}}else if (current_button == KEY3){    led_fd = open("/dev/led2",O_RDWR,755);    switch(x%2)                  {                  case 0:                       ioctl(led_fd,OFF,2);                      x++;                    printf("Turn led2 OFF.\n");                    break;                  case 1:                       ioctl(led_fd,ON,2);                      x++;                    printf("Turn led2 ON.\n");                    break;}}        else if (current_button == KEY4){    led_fd = open("/dev/led3",O_RDWR,755);    switch(y%2)                  {                  case 0:                       ioctl(led_fd,OFF,3);                      y++;                    printf("Turn led3 OFF.\n");                    break;                 case 1:                       ioctl(led_fd,ON,3);                      y++;                    printf("Turn led3 ON.\n");                    break;}}    }}ioctl(led_fd,OFF);    close(led_fd);    close(button_fd);return 0;}

编译以后和前面LED操作一样，在开发板上安装led驱动和按键驱动。

执行后按奇数下亮，偶数下灭。

对于定时器还不是太理解，以后将进一步理解定时器。

1 0