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system heap dynamic size

Posted by vincent on November 16, 2012

as we know that the configTOTAL_HEAP_SIZE value is used by FreeRTOS to manage all running task.
i want to know the system heap dynamtic size which is defined in startup_stm32f2xx.s
Heap_Size EQU 0x00004000

Heap_Mem SPACE Heap_Size

i really want to get the dynamic value used in MALLOC and FREE.
anyone knows that ?


RE: system heap dynamic size

Posted by Dave on November 16, 2012
I don't think I understand your question. The heap that is defined in the code you post will only be used if either your project uses heap_3.c (heap_1, heap_2 and heap_4 do not use it), or your code uses malloc() and free() directly rather than pvPortMalloc() and vPortFree().

If you don't use malloc() and free(), and use don't use heap_3.c, and you are not using library functions that use malloc(), then you can set to size to 0 if the linker will let you, or 4 if the linker won't let you as the RAM is just being wasted.

RE: system heap dynamic size

Posted by vincent on November 18, 2012
I wonder to know that the memory is allocated from the HEAP my code define when i use MALLOC / FREEfunction.
as my application use JSON library which use more MALLOC and FREE, i found that the system become halt sometime.
i try to find if the HEAP to be used is not enough large or other issue.


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