Sample Code for Zephyr OS

main.c

#include <zephyr.h>
#include <misc/printk.h>


/* size of stack area used by each thread */
#define STACKSIZE 1024

K_SEM_DEFINE(sem, 0, 1);
K_MUTEX_DEFINE(mutex);


extern void t01_entry(void);
extern void t02_entry(void);
extern void t03_entry(void);
extern void t04_entry(void);
extern void print_counter_value(void);

K_THREAD_DEFINE(t01_id, STACKSIZE, t01_entry, NULL, NULL, NULL, 1, 0, K_NO_WAIT);
K_THREAD_DEFINE(t02_id, STACKSIZE, t02_entry, NULL, NULL, NULL, 1, 0, K_NO_WAIT);
K_THREAD_DEFINE(t03_id, STACKSIZE, t03_entry, NULL, NULL, NULL, 1, 0, K_NO_WAIT);
K_THREAD_DEFINE(t04_id, STACKSIZE, t04_entry, NULL, NULL, NULL, 1, 0, K_NO_WAIT);

void main(void) {
	k_sched_time_slice_set(1000, 0);
}

void t01_entry(void) {
	while(1) {
		printk("T01\n");
		k_sem_give(&sem);
		// k_sleep(1500);
	}
}

void t02_entry(void) {
	while(1) {
		if ( k_sem_take(&sem, K_FOREVER) == 0) {
			printk("T02\n");
		}
	}
}

void t03_entry(void) {
	while(1) {
		printk("T03\n");
		// k_mutex_lock(&mutex, K_FOREVER);
		// print_counter_value();
		// k_mutex_unlock(&mutex);
		return ;
	}
}

void t04_entry(void) {
	while(1) {
		printk("T04\n");
		// k_mutex_lock(&mutex, K_FOREVER);
		// print_counter_value();
		// k_mutex_unlock(&mutex);
		return ;
	}
}

int counter = 0;

void print_counter_value(void) {
	counter ++;
	printk("Counter Value:  %d\n", counter);
}