drvtest.c

在Linux系统下

#include <unistd.h>
#include <stdio.h>
#include <fcntl.h>

#include "drv.h"

static int fd = -1;
static int d;

/*
 * leddrv application code, the code of Linux application to use driver code
 * compile :
 *          $/usr/local/arm/2.95.3/bin/arm-linux-gcc -o drvtest drvtest.c
 *          $cp helloworld /tftpboot/examples
 * run in target:
 *          #mount 192.168.1.180:/tftpboot/ /mnt/nfs
 *          #cd /mnt/nfs/examples
 *          #insmod drv
 *          #mknod /dev/drvtest c 100 0
 *          #./drvtest
 */
int main(int argc, char **argv)
{
	int ret;
	
	fd=open("/dev/drvtest",O_RDWR);
	if(fd<0) 
	{
		printf("Can't open\n");
		return -1;
	}
	else
	{
		printf("open OK %x\n", fd);
	}

	while(1)
	{
		printf("enter a number:\n");
		scanf("%d", &d);
                
		
		
		ret = write(fd, &d, 4);

                //ret = read(fd, &d, 4);
	}

   	close(fd);
   	
  	return 0;
}