6678 memory problem

Hi Yang,

In your example, the array a[20000] is allocated from stack, so it will occupy 80000bytes which is larger than the size of stack. If you insist to allocate the array in stack, just extend the size of stack to fit the array. And place .stack section in larger space such as MSMCRAM or DDR3 if needed.

Allen

Hi,

When you declare a variable in a function, it will be stored in the stack. Here, you declare your array in the main function.

Your stack's size is 0x10000, and will be in L2 memory (.stack  : > L2SRAM)

Your array's size is 20000 floats = 20000 * 4 bytes = 0x13880

Your array does not feet into the stack, you have a stack overflow...

You can solve this problem in to ways :

1 ) Increase the size of the stack :

Linker file:

-stack 0x10000 here, put more than 0x13880, because other things are put in the stack too.

2 ) Declare your array as global (declare it outside functions) You should do it this way, the stack is not usualy used to save so big data.:

float a[20000];

void main() { ... }

It will be in L2 ( I think it is because of  .data  : > L2SRAM )

If you want to put it somewhere else (in MSMCSRAM for exemple), you can create a section, tell the linker where to store this section, and put your array in this section :

SECTIONS
{
  .cinit  : > L2SRAM
  .cio   : > L2SRAM
  .const  : > L2SRAM
  .data         : > L2SRAM
  .far   : > L2SRAM
  .fardata  : > L2SRAM
  .stack  : > L2SRAM
  .sysmem  : > L2SRAM
  .text         : > L2SRAM
  .neardata  : > L2SRAM
  .bss   : > L2SRAM
  
  .fasttext:  >       L2SRAM
  .switch:    >       L2SRAM
  .heap       >       L2SRAM
  .rodata     > L2SRAM
  .boot: > L2SRAM

.my_new_section : > MSMCSRAM
}

and when declaring your variable :

#pragma DATA_SECTION(a,".my_new_section");

float a[20000];

main(){...}

Regards,

Benoit