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Author | strongerHuang

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xTaskCreate(LED_Task, "LED_Task", 128, NULL, 6, NULL);

If we want to elaborate on this question, there are many related knowledge points involved. Below are a few important related contents to answer this question.

Memory allocation is generally divided into: static and dynamic allocation.

1. Static Memory Allocation

Simply put, it is memory allocated at compile time. You can understand it as when the chip is powered on, a specified area (address) of memory is occupied.

There are generally a few situations, such as:

Startup allocation stack:

Stack_Size    EQU     0x400

Defining a static variable is the easiest example to understand:

static int a;

Defining a global variable/array, etc.:

int char;

2. Dynamic Memory Allocation

void UART_Send(char *p){  char buf[10];  //......}

1. Global Array (Stack)

The memory for FreeRTOS is allocated in the FreeRTOSConfig.h file as a global array, and the size of this memory is allocated by the user based on the situation, for example:

#define configTOTAL_HEAP_SIZE     ((size_t)(10 * 1024))

2. Creating Tasks

FreeRTOS creates tasks, allocating stack size, for example: 128 “words”

xTaskCreate(LED_Task, "LED_Task", 128, NULL, 6, NULL);

Reminder: Here “word” is the unit, for example: uint32_t

3. Deleting Tasks

FreeRTOS deletes tasks, calling the “vPortFree()” function to release the corresponding memory.

Having read this, can you answer the initial question?

The answer is: FreeRTOS is not dynamically allocated memory, it only simulates the way of dynamic allocation, and the actual memory is statically allocated.

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