Linker basic option --stack_size

Mohammad Nasser

Intellectual 280 points

Other Parts Discussed in Thread: MSP430F5438A

hi,

i am using code composer on msp430f5438a for developing an application with FreeRTOS.

i just want to ask about the basic option in the linker "--stack_size", is this stak for the main.

becaus FreeRTOS allocate for it tasks stack on the heap. so i want to know , for what is this stack in the linker.

Regards.

over 13 years ago

0 desouza over 13 years ago

TI__Guru**** 171729 points

Hi,

Yes, the linker option --stack_size sets the amount of stack used by the overall code. Any RTOS may use that or allocate a separate stack space to be used exclusively by itself.

Per your information it seems the FreeRTOS allocates its own stack dynamically. Therefore the amount of memory will be determined by the heap size, which is set with the option --heap_size

Check:

http://processors.wiki.ti.com/index.php/Code_Generation_Tools_FAQ#Q:_What.27s_the_difference_between_HEAP_and_STACK.3F

Hope this helps,

Rafael

0 Mohammad Nasser over 13 years ago in reply to desouza

Intellectual 280 points

Hi,

i have a question now after looking at the link you gave to me.

is the ".bss"- section (which is for Global and static variables) a part of the RAM or is it part of the flash memory?

0 desouza over 13 years ago in reply to Mohammad Nasser

TI__Guru**** 171729 points

Hi,

The .bss section holds uninitialized variables, thus needs to be allocated in RAM.

For additional details on this subject, check section 4.3.7 of the MSP430 Compiler User's Guide (link to this documentation is at this wiki page).

Hope this helps,

Rafael

0 Mohammad Nasser over 13 years ago in reply to desouza

Intellectual 280 points

Hi,

thanl you for your answer. but i want still to know for what the stack size in linker is used.

is it only for the startup code, or it will be used as stack size for every function that will be called. i am talking now in general and without RTOS.

Regards

0 desouza over 13 years ago in reply to Mohammad Nasser

TI__Guru**** 171729 points

Hi,

Mohammad Nasser said:

it will be used as stack size for every function that will be called. i am talking now in general and without RTOS.

That is the correct answer - keep in mind that not only return addresses are stored in the stack, but also parameters passed to functions (thus use pointers when passing parameters to minimize stack usage).

Cheers,

Rafael

0 Mohammad Nasser over 13 years ago in reply to desouza

Intellectual 280 points

Hi Rafael,

i read this statement in the documentaion of a RTOS:

"The MSP430 does not have a dedicated interrupt stack, make sure to reserve enough stack space for interrupts in each thread stack."

i want please to know if this statement is correct.

Regargds.

Code Composer Studio™︎

Code Composer Studio forum

Linker basic option --stack_size