utask_example_4.c

Example of spawning new tasks from running ones.

#include "utask.h"
#include "leds.h"
#include "timer.h"
#include "uart.h"

void timer_isr()            //called 1000 times a second
{
  utask_sleep_process();
}

int btn_press_counter = 0;

void button_isr()
{
    btn_press_counter++;
}

void task_do_something(utask* t)
{
    //do yer stuff here
}

void task_spawn_on_button_press(utask* t)
{
    switch (t->istate)
    {
        case 0:
            utask_wait_nzero(t,&btn_press_counter,1000000);     //wait looooong time
            t->istate = 1;
            break;
            
        case 1:
            if (t->sleep != 0)  //the task has been awakened -> btn_press_counter != 0
            {
                utask_add(task_do_something);       //spawn new task
                btn_press_counter--;
            }
            t->istate = 0;
            break;
    }
}


int main ()
{
    timer_init();
    uart_init();
    utask_init();

    utask_add(task_spawn_on_button_press);
    
    while (1)
    {
        utask_schedule();
    }
    return 0;
}