/*  PARALLEL    periodic scheduled task that toggles parallel port on each invocation.    Originally by Michael "FZ" Barabanov    Modified by Victor Yodaiken yodaiken@cs.nmt.edu     (c) Barabanov,Yodaiken 1997,1998    */#include <linux/module.h>#include <linux/kernel.h>#include <rtl_fifo.h>#include <rtl_time.h>#include <rtl_sched.h>#include <asm/io.h>#include <linux/cons.h>#include "common.h"#define PERIOD 500000RT_TASK mytask;static int output = 0xffff;void fun(int t) {	while (1) {		conpr("H");		outb(output, LPT_PORT);		output = ~output;		rt_task_wait();	}}int init_module(void){        printk("Starting parallel port module\n");	rt_task_init(&mytask, fun, 1, 3000, 4);	rt_task_make_periodic(&mytask, rt_get_time(), PERIOD);	return 0;}void cleanup_module(void){	rt_task_delete(&mytask);}