sw_show.c

一个在linux下的驱动程序的例子

#include "stdio.h"
#include "sys/types.h"
#include "sys/ioctl.h"
#include "stdlib.h"
#include "termios.h"
#include "sys/stat.h"
#include "fcntl.h"
#include "sys/time.h"

//unsigned char ledtab[]={0x0e,0x0d,0x0b,0x07};


int main(void)
{int pb_dev,pb_sw,m,len,i,buffer;
	
   
  len=1;
  pb_dev=open("/dev/io_pb",O_RDWR);
 if(pb_dev<0)
 {
  printf("can't open device\n");
  return(0);
 }

pb_sw=open("/dev/io_sw",O_RDWR);
 if(pb_sw<0)
 {
  printf("can't open device\n");
  return(0);
 }



   printf("led test show. press ctrl+c to exit  \n");
	 
	buffer=0x0f;
	while(1)
	{
		write(pb_dev,&buffer,len);
		read(pb_sw,&buffer,1);
		if(buffer!=0x0f){
			write(pb_dev,&buffer,len);
		}
		usleep(50000);

	}
        close(pb_dev);
        close(pb_sw);
	return 0;

}