Move RTOS Stack and HEAP to other RAM Region?

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1

Does any one know if it is possible to remap or move the stack and heap to another RAM Address?

I’m using a STM32L431CC microcontroller which has two RAM sections:
RAM (xrw) : ORIGIN = 0x20000000, LENGTH = 64K
RAM2 (xrw) : ORIGIN = 0x10000000, LENGTH = 16K

For my rtos configuration the 16K RAM2 would be sufficient.
I’m using heap4.

Does any one know how I can move the rtos into this ram region?

I don’t have a special reason to do this but I was wondering if it is possible to do.

2

That tends to be controlled by the linker control file. If using one of the FreeRTOS heap routines that define a static array for the heap, you will normally need to add an attribute to the definition of that array to put it into a special linker section.

3

Where do I find this definition of the array?
I know that the attribute should be:

__attribute__ ((used,section(".ram2")))
4

Heap4’s backing buffer is defined here: FreeRTOS-Kernel/heap_4.c at 1b8a4244bdd911f156ce5bc6f9f13dcde68228cb · FreeRTOS/FreeRTOS-Kernel · GitHub

To apply the attribute, you would define configAPPLICATION_ALLOCATED_HEAP to 1 in your FreeRTOSConfig.h, set configTOTAL_HEAP_SIZE to the size you want, and then define ucHeap.