DevHeads IoT Integration Server•4mo ago

How can I manage communication between tasks using queues in FreeRTOS?

How can I manage communication between tasks using queues in FreeRTOS? My queue data seems to be getting lost, and I'm encountering the error: "Queue send failed". Here's my queue creation and send code:

xQueue = xQueueCreate(10, sizeof(int));
int value = 42;
xQueueSend(xQueue, &value, portMAX_DELAY);

xQueue = xQueueCreate(10, sizeof(int));
int value = 42;
xQueueSend(xQueue, &value, portMAX_DELAY);

@Middleware & OS @Helper

Solution:

@ZacckOsiemo It's been resolved and my code works better now after adding the function that confirms if the queue was actually created, regarding d syntax error seems I didn't add a ; were it was required, this little error caused me almost a day of headache, thanks for the help guys, @everyone This is my code now 👇...

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10 Replies

ZacckOsiemo•4mo ago

Are you checking that the queue is created successfully, Is there enough space on the heap? Are you calling xQueueSend in an ISR?

Boss lady•4mo ago

@ZacckOsiemo Am checking if it's created successfully, cause I keep getting the error queue send failed

ZacckOsiemo•4mo ago

start by checking that its actually created, then ensure you are calling xQueueSend in the correct context

youcef_ali•4mo ago

First check that your queue has been created correctly, and before sending check that you have anough/available space in your queue

Boss lady•4mo ago

I tried adding a function to check if the queue is successfully created but now having a syntax error This my code

// Include necessary FreeRTOS header files
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"

// Declare the queue handle
QueueHandle_t xQueue;

// Task1 function
void Task1(void* pvParameters) {
    // Check if queue is created
    if (xQueue == NULL) {
        // Queue not created
        printf("Queue not created!\n");
        vTaskDelete(NULL);
    }

    int value = 42;
    while (1) {
        // Send value to the queue
        if (xQueueSend(xQueue, &value, portMAX_DELAY) != pdPASS) {
            // Queue send failed
            printf("Queue send failed!\n");
        }

        // Delay for a certain interval
        vTaskDelay(pdMS_TO_TICKS(1000));
    }
}

// Task2 function
void Task2(void* pvParameters) {
    // Check if queue is created
    if (xQueue == NULL) {
        // Queue not created
        printf("Queue not created!\n");
        vTaskDelete(NULL);
    }

    int receivedValue;
    while (1) {
        // Receive value from the queue
        if (xQueueReceive(xQueue, &receivedValue, portMAX_DELAY) == pdPASS) {
            // Successfully received value from the queue
            printf("Received value: %d\n", receivedValue);
        }

        // Delay for a certain interval
        vTaskDelay(pdMS_TO_TICKS(1000))
    }
}

int main() {
    // Create the queue
    xQueue = xQueueCreate(10, sizeof(int));

    // Check if queue is created
    if (xQueue == NULL) {
        // Queue creation failed
        printf("Queue creation failed!\n");
        return 1;
    }

    // Create Task1
    xTaskCreate(Task1, "Task1", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 1, NULL);

    // Create Task2
    xTaskCreate(Task2, "Task2", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 1, NULL)

    // Start scheduler
    vTaskStartScheduler();

    while(1); // Should never reach here
    return 0;
}

// Include necessary FreeRTOS header files
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"

// Declare the queue handle
QueueHandle_t xQueue;

// Task1 function
void Task1(void* pvParameters) {
    // Check if queue is created
    if (xQueue == NULL) {
        // Queue not created
        printf("Queue not created!\n");
        vTaskDelete(NULL);
    }

    int value = 42;
    while (1) {
        // Send value to the queue
        if (xQueueSend(xQueue, &value, portMAX_DELAY) != pdPASS) {
            // Queue send failed
            printf("Queue send failed!\n");
        }

        // Delay for a certain interval
        vTaskDelay(pdMS_TO_TICKS(1000));
    }
}

// Task2 function
void Task2(void* pvParameters) {
    // Check if queue is created
    if (xQueue == NULL) {
        // Queue not created
        printf("Queue not created!\n");
        vTaskDelete(NULL);
    }

    int receivedValue;
    while (1) {
        // Receive value from the queue
        if (xQueueReceive(xQueue, &receivedValue, portMAX_DELAY) == pdPASS) {
            // Successfully received value from the queue
            printf("Received value: %d\n", receivedValue);
        }

        // Delay for a certain interval
        vTaskDelay(pdMS_TO_TICKS(1000))
    }
}

int main() {
    // Create the queue
    xQueue = xQueueCreate(10, sizeof(int));

    // Check if queue is created
    if (xQueue == NULL) {
        // Queue creation failed
        printf("Queue creation failed!\n");
        return 1;
    }

    // Create Task1
    xTaskCreate(Task1, "Task1", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 1, NULL);

    // Create Task2
    xTaskCreate(Task2, "Task2", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 1, NULL)

    // Start scheduler
    vTaskStartScheduler();

    while(1); // Should never reach here
    return 0;
}

ZacckOsiemo•4mo ago

whats the error?

Boss lady•4mo ago

Syntax error

ZacckOsiemo•4mo ago

yeah what syntax error

Solution

Boss lady•4mo ago

// Include necessary FreeRTOS header files
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"

// Declare the queue handle
QueueHandle_t xQueue;

// Task1 function
void Task1(void* pvParameters) {
    // Check if queue is created
    if (xQueue == NULL) {
        // Queue not created
        printf("Queue not created!\n");
        vTaskDelete(NULL);
    }

    int value = 42;
    while (1) {
        // Send value to the queue
        if (xQueueSend(xQueue, &value, portMAX_DELAY) != pdPASS) {
            // Queue send failed
            printf("Queue send failed!\n");
        }

        // Delay for a certain interval
        vTaskDelay(pdMS_TO_TICKS(1000));
    }
}

// Task2 function
void Task2(void* pvParameters) {
    // Check if queue is created
    if (xQueue == NULL) {
        // Queue not created
        printf("Queue not created!\n");
        vTaskDelete(NULL);
    }

    int receivedValue;
    while (1) {
        // Receive value from the queue
        if (xQueueReceive(xQueue, &receivedValue, portMAX_DELAY) == pdPASS) {
            // Successfully received value from the queue
            printf("Received value: %d\n", receivedValue);
        }

        // Delay for a certain interval
        vTaskDelay(pdMS_TO_TICKS(1000)); // Fixed: Added missing semicolon
    }
}

int main() {
    // Create the queue
    xQueue = xQueueCreate(10, sizeof(int));

    // Check if queue is created
    if (xQueue == NULL) {
        // Queue creation failed
        printf("Queue creation failed!\n");
        return 1;
    }

    // Create Task1
    xTaskCreate(Task1, "Task1", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 1, NULL);

    // Create Task2
    xTaskCreate(Task2, "Task2", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 1, NULL); // Fixed: Added missing semicolon

    // Start scheduler
    vTaskStartScheduler();

    while(1); // Should never reach here
    return 0;
}

// Include necessary FreeRTOS header files
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"

// Declare the queue handle
QueueHandle_t xQueue;

// Task1 function
void Task1(void* pvParameters) {
    // Check if queue is created
    if (xQueue == NULL) {
        // Queue not created
        printf("Queue not created!\n");
        vTaskDelete(NULL);
    }

    int value = 42;
    while (1) {
        // Send value to the queue
        if (xQueueSend(xQueue, &value, portMAX_DELAY) != pdPASS) {
            // Queue send failed
            printf("Queue send failed!\n");
        }

        // Delay for a certain interval
        vTaskDelay(pdMS_TO_TICKS(1000));
    }
}

// Task2 function
void Task2(void* pvParameters) {
    // Check if queue is created
    if (xQueue == NULL) {
        // Queue not created
        printf("Queue not created!\n");
        vTaskDelete(NULL);
    }

    int receivedValue;
    while (1) {
        // Receive value from the queue
        if (xQueueReceive(xQueue, &receivedValue, portMAX_DELAY) == pdPASS) {
            // Successfully received value from the queue
            printf("Received value: %d\n", receivedValue);
        }

        // Delay for a certain interval
        vTaskDelay(pdMS_TO_TICKS(1000)); // Fixed: Added missing semicolon
    }
}

int main() {
    // Create the queue
    xQueue = xQueueCreate(10, sizeof(int));

    // Check if queue is created
    if (xQueue == NULL) {
        // Queue creation failed
        printf("Queue creation failed!\n");
        return 1;
    }

    // Create Task1
    xTaskCreate(Task1, "Task1", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 1, NULL);

    // Create Task2
    xTaskCreate(Task2, "Task2", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 1, NULL); // Fixed: Added missing semicolon

    // Start scheduler
    vTaskStartScheduler();

    while(1); // Should never reach here
    return 0;
}

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How can I manage communication between tasks using queues in FreeRTOS?