Control passing using FreeRTOS notifications.

main_passcontrol.c

/**
 * Adapted from: https://www.freertos.org/RTOS_Task_Notification_As_Binary_Semaphore.html
*/

#include <stdio.h>
#include <pthread.h>

#include "FreeRTOS.h"
#include "semphr.h"

#define TASK_LOOP_DELAY 30

TaskHandle_t passcontrol_h_task1 = NULL;
TaskHandle_t passcontrol_h_task2 = NULL;

void passcontrol_task1(void *_)
{
    uint16_t c1 = 0;
    while (1)
    {
        xTaskNotifyGive(passcontrol_h_task2);
        printf("[1] C1:%hu\r\n", c1);
        c1++;
        ulTaskNotifyTake(0, portMAX_DELAY);
        vTaskDelay(pdMS_TO_TICKS(TASK_LOOP_DELAY));
    }
}

void passcontrol_task2(void *_)
{
    uint16_t c2 = 0;
    while (1)
    {
        ulTaskNotifyTake(0, portMAX_DELAY);
        printf("[2] C2:%hu\r\n", c2);
        c2++;
        xTaskNotifyGive(passcontrol_h_task1);
        vTaskDelay(pdMS_TO_TICKS(TASK_LOOP_DELAY));
    }
}

void main_passcontrol()
{
    xTaskCreate(passcontrol_task1, "T1", configMINIMAL_STACK_SIZE, NULL, 1, &passcontrol_h_task1);
    xTaskCreate(passcontrol_task2, "T2", configMINIMAL_STACK_SIZE, NULL, 1, &passcontrol_h_task2);
    vTaskStartScheduler();

    for (;;)
        ;
}