test_led.c

来自「这是motorola公司的powerpc芯片上的嵌入式linux上的驱动程序和测」· C语言 代码 · 共 57 行

/* (C) Copyright 2002,12
 * 
 * Qi zhaoling 
 * All rights left.
 *
 *
 * led test application
 *
 *
 * $Id: led_test.c, v 1.2 2002/12/14 16:12:29 wd Exp $
 *
 ***********************************************************************/
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>

main()
{
	int testdev,num=10;
	int err;

	char buf[2] = {0xFF,0xFF};
	char buf2[2] = {0x0,0x0};

	testdev = open("/dev/ut_led",O_RDWR);

	if ( testdev < 0  )
	{
		printf("Cann't open file \n");
		exit(0);
	}


	while(num)
	{
		err = write(testdev, buf, 2);
		if(2 != err )
                {
			printf("write error: %d\n",err);
                }
		sleep(1);

		err = write(testdev, buf2, 2);
		if(2 != err )
		{
			printf("write error: %d\n",err);
		}
		sleep(1);
                /*num--;*/
	}

	close(testdev);
}