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/* this is a very simple program meant to demonstrate

   a basic use of time, alarms and alarm-handling functions

   in eCos */

#include <cyg/kernel/kapi.h>

#include <stdio.h>

#define NTHREADS 1

#define STACKSIZE 4096

static cyg_handle_t thread[NTHREADS];

static cyg_thread thread_obj[NTHREADS];

static char stack[NTHREADS][STACKSIZE];

static void alarm_prog( cyg_addrword_t data );

/* we install our own startup routine which sets up

    threads and starts the scheduler */

void cyg_user_start(void)

{

  cyg_thread_create(4, alarm_prog, (cyg_addrword_t) 0,

                    "alarm_thread", (void *) stack[0],

                    STACKSIZE, &thread[0], &thread_obj[0]);

  cyg_thread_resume(thread[0]);

}

/* we need to declare the alarm handling function (which is

   defined below), so that we can pass it to

   cyg_alarm_initialize() */

cyg_alarm_t test_alarm_func;

/* alarm_prog() is a thread which sets up an alarm which is then

   handled by test_alarm_func() */

static void alarm_prog(cyg_addrword_t data)

{

  cyg_handle_t test_counterH, system_clockH, test_alarmH;

  cyg_tick_count_t ticks;

  cyg_alarm test_alarm;

  unsigned how_many_alarms = 0, prev_alarms = 0, tmp_how_many;

  system_clockH = cyg_real_time_clock();

  cyg_clock_to_counter(system_clockH, &test_counterH);

  cyg_alarm_create(test_counterH, test_alarm_func,

                   (cyg_addrword_t) &how_many_alarms,

                   &test_alarmH, &test_alarm);

  cyg_alarm_initialize(test_alarmH, cyg_current_time()+200, 200);

  /* get in a loop in which we read the current time and

     print it out, just to have something scrolling by */

  for (;;) {

    ticks = cyg_current_time();

    printf("Time is %llu\n", ticks);

    /* note that we must lock access to how_many_alarms, since the

       alarm handler might change it.  this involves using the

       annoying temporary variable tmp_how_many so that I can keep the

       critical region short */

    cyg_scheduler_lock();

    tmp_how_many = how_many_alarms;

    cyg_scheduler_unlock();

    if (prev_alarms != tmp_how_many) {

      printf("  ---> alarm calls so far: %u\n", tmp_how_many);

      prev_alarms = tmp_how_many;

    }

    cyg_thread_delay(30);

  }

}

/* test_alarm_func() is invoked as an alarm handler, so

   it should be quick and simple.  in this case it increments

   the data that is passed to it. */

void test_alarm_func(cyg_handle_t alarmH, cyg_addrword_t data)

{

  ++*((unsigned *) data);

}