topic Re: use of stack in lcf file. in ColdFire/68K Microcontrollers and Processors

use of stack in lcf file.

ash_aricent — Tue, 07 Apr 2009 17:44:38 GMT

Please help me. I am stuck with this for more than a month.

Here are some content of a standard lcf file.

.custom :
    {
        ___HEAP_START    = .;
        ___heap_addr    = ___HEAP_START;
        ___HEAP_END        = ___HEAP_START + ___heap_size;
        ___SP_END        = ___HEAP_END;
        ___SP_INIT        = ___SP_END + ___stack_size;
        ___free_mem     = ___SP_INIT;

. = ALIGN (0x4);
} >> userram

Where does RTOS/Compiler use this heap and stack ?

We are working with MCF520X mp.

Re: use of stack in lcf file.

CrasyCat — Tue, 07 Apr 2009 19:36:44 GMT

Hello

The startup code is initializing the stack according to the value of __SP_INIT in file CF_startup.c.

The heap is allocated in alloc.c according to settings of ___heap_addr.

CF_Startup.c is stored in {Install}\ColdFire_Support\Runtime\Runtime_ColdFire\Source

alloc.c can be found in {Install}\ColdFire_Support\msl\MSL_C\MSL_Common\Src

CrasyCat

Re: use of stack in lcf file.

ash_aricent — Tue, 21 Apr 2009 18:47:16 GMT

Let me explain my question.

Is it used for

a) Global variable

b) local variable

c) function calls

d) thread context switch

e) dynamic memory allocation

Consider that we are using some RTOS also.

Re: use of stack in lcf file.

CrasyCat — Fri, 24 Apr 2009 16:01:48 GMT

Hello

Basically and this is a standard way of operation for an ANSI C compiler

- Heap is used for dynamic memory allocation

- stack is used for function calls, local variables and parameters.

CrasyCat