xTaskCreate() function in FreeRTOS - Mini Project: Build & Apply

Creating a Task with xTaskCreate() in FreeRTOS

📖 Scenario: You are working on a simple embedded system using FreeRTOS. You want to create a task that blinks an LED repeatedly.

🎯 Goal: Learn how to use the xTaskCreate() function to create a FreeRTOS task that runs a simple LED blinking function.

📋 What You'll Learn

Create a task function called vBlinkTask that toggles an LED.

Create a task handle variable called xBlinkTaskHandle.

Use xTaskCreate() to create the vBlinkTask task.

Start the FreeRTOS scheduler with vTaskStartScheduler().

Print a message inside the task to indicate it is running.

💡 Why This Matters

🌍 Real World

Creating tasks is essential in embedded systems to run multiple functions like sensor reading, communication, and control in parallel.

💼 Career

Understanding <code>xTaskCreate()</code> is fundamental for embedded software engineers working with FreeRTOS to build responsive and efficient applications.

1

Define the task function vBlinkTask

Write a task function called vBlinkTask that takes a void *pvParameters argument and contains an infinite loop with a comment // Toggle LED here inside the loop.

FreeRTOS

# Define the task function vBlinkTask
# Your code here

Need a hint?

Task functions in FreeRTOS have the form void TaskName(void *pvParameters) and run an infinite loop.

2

Declare a task handle variable xBlinkTaskHandle

Declare a variable called xBlinkTaskHandle of type TaskHandle_t and initialize it to NULL.

FreeRTOS

void vBlinkTask(void *pvParameters) {
    for(;;) {
        // Toggle LED here
    }
}

// Declare task handle variable
# Your code here

Need a hint?

Task handles are used to reference tasks after creation. Initialize it to NULL.

3

Create the task using xTaskCreate()

Use xTaskCreate() to create the task vBlinkTask with the name "BlinkTask", stack size configMINIMAL_STACK_SIZE, no parameters (NULL), priority 1, and store the handle in &xBlinkTaskHandle.

FreeRTOS

void vBlinkTask(void *pvParameters) {
    for(;;) {
        // Toggle LED here
    }
}

TaskHandle_t xBlinkTaskHandle = NULL;

// Create the task using xTaskCreate
# Your code here

Need a hint?

The xTaskCreate() function creates a task. Pass the function name, task name, stack size, parameters, priority, and handle pointer.

4

Start the scheduler and print inside the task

Add a printf("Blink task running\n") inside the infinite loop of vBlinkTask. Then call vTaskStartScheduler() after creating the task.

FreeRTOS

void vBlinkTask(void *pvParameters) {
    for(;;) {
        // Toggle LED here
        // Add printf here
    }
}

TaskHandle_t xBlinkTaskHandle = NULL;

xTaskCreate(vBlinkTask, "BlinkTask", configMINIMAL_STACK_SIZE, NULL, 1, &xBlinkTaskHandle);

// Start the scheduler
# Your code here

Need a hint?

Use printf to show the task is running. Then start the FreeRTOS scheduler with vTaskStartScheduler().