Hands-On RTOS with Microcontrollers

Heap memory

The heap is the portion of memory that is used when a dynamic allocation using malloc is called. It is also where a FreeRTOS task stack and task control block (TCB) are stored when they are created by calling xTaskCreate().

In an MCU FreeRTOS system, there will typically be two heaps created:

• System heap: Defined in the startup and linker scripts described previously. This will not be available for use by the final application code when allocating space for RTOS primitives.
• FreeRTOS heap: Used when creating tasks and other primitives and defined in Inc\FreeRTOSConfig.h. It can be resized by adjusting the following line:

#define configTOTAL_HEAP_SIZE ((size_t)15360)

Currently, this line is defining a 15 KB heap. This heap must ...