I checked the .ld file or the linker script. Since My code is generated by the STM32 Cube MX, my file is named STM32H755ZITX_RAM.ld.
Here is the content of the file:
/*
******************************************************************************
**
** File : LinkerScript.ld
**
**
** Abstract : Linker script for STM32H7 series
** 256Kbytes RAM_EXEC and 256Kbytes RAM
**
** Set heap size, stack size and stack location according
** to application requirements.
**
** Set memory bank area and size if external memory is used.
**
** Target : STMicroelectronics STM32
**
** Distribution: The file is distributed as is, without any warranty
** of any kind.
**
*****************************************************************************
** @attention
**
** Copyright (c) 2019 STMicroelectronics.
** All rights reserved.
**
** This software component is licensed by ST under BSD 3-Clause license,
** the "License"; You may not use this file except in compliance with the
** License. You may obtain a copy of the License at:
** opensource.org/licenses/BSD-3-Clause
**
****************************************************************************
*/
/* Entry Point */
ENTRY(Reset_Handler)
/* Highest address of the user mode stack */
_estack = 0x24080000; /* end of RAM */
/* Generate a link error if heap and stack don't fit into RAM */
_Min_Heap_Size = 0x200 ; /* required amount of heap */
_Min_Stack_Size = 0x400 ; /* required amount of stack */
/* Specify the memory areas */
MEMORY
{
RAM_EXEC (rx) : ORIGIN = 0x24000000, LENGTH = 256K
RAM (xrw) : ORIGIN = 0x24040000, LENGTH = 256K
}
/* Define output sections */
SECTIONS
{
/* The startup code goes first into RAM_EXEC */
.isr_vector :
{
. = ALIGN(4);
KEEP(*(.isr_vector)) /* Startup code */
. = ALIGN(4);
} >RAM_EXEC
/* The program code and other data goes into RAM_EXEC */
.text :
{
. = ALIGN(4);
*(.text) /* .text sections (code) */
*(.text*) /* .text* sections (code) */
*(.glue_7) /* glue arm to thumb code */
*(.glue_7t) /* glue thumb to arm code */
*(.eh_frame)
KEEP (*(.init))
KEEP (*(.fini))
. = ALIGN(4);
_etext = .; /* define a global symbols at end of code */
} >RAM_EXEC
/* Constant data goes into RAM_EXEC */
.rodata :
{
. = ALIGN(4);
*(.rodata) /* .rodata sections (constants, strings, etc.) */
*(.rodata*) /* .rodata* sections (constants, strings, etc.) */
. = ALIGN(4);
} >RAM_EXEC
.ARM.extab : { *(.ARM.extab* .gnu.linkonce.armextab.*) } >RAM_EXEC
.ARM : {
__exidx_start = .;
*(.ARM.exidx*)
__exidx_end = .;
} >RAM_EXEC
.preinit_array :
{
PROVIDE_HIDDEN (__preinit_array_start = .);
KEEP (*(.preinit_array*))
PROVIDE_HIDDEN (__preinit_array_end = .);
} >RAM_EXEC
.init_array :
{
PROVIDE_HIDDEN (__init_array_start = .);
KEEP (*(SORT(.init_array.*)))
KEEP (*(.init_array*))
PROVIDE_HIDDEN (__init_array_end = .);
} >RAM_EXEC
.fini_array :
{
PROVIDE_HIDDEN (__fini_array_start = .);
KEEP (*(SORT(.fini_array.*)))
KEEP (*(.fini_array*))
PROVIDE_HIDDEN (__fini_array_end = .);
} >RAM_EXEC
/* used by the startup to initialize data */
_sidata = LOADADDR(.data);
/* Initialized data sections goes into RAM, load LMA copy after code */
.data :
{
. = ALIGN(4);
_sdata = .; /* create a global symbol at data start */
*(.data) /* .data sections */
*(.data*) /* .data* sections */
. = ALIGN(4);
_edata = .; /* define a global symbol at data end */
} >RAM AT> RAM_EXEC
/* Uninitialized data section */
. = ALIGN(4);
.bss :
{
/* This is used by the startup in order to initialize the .bss secion */
_sbss = .; /* define a global symbol at bss start */
__bss_start__ = _sbss;
*(.bss)
*(.bss*)
*(COMMON)
. = ALIGN(4);
_ebss = .; /* define a global symbol at bss end */
__bss_end__ = _ebss;
} >RAM
/* User_heap_stack section, used to check that there is enough RAM left */
._user_heap_stack :
{
. = ALIGN(8);
PROVIDE ( end = . );
PROVIDE ( _end = . );
. = . + _Min_Heap_Size;
. = . + _Min_Stack_Size;
. = ALIGN(8);
} >RAM
/* Remove information from the standard libraries */
/DISCARD/ :
{
libc.a ( * )
libm.a ( * )
libgcc.a ( * )
}
.ARM.attributes 0 : { *(.ARM.attributes) }
}
Since I am pretty new with this topic, I could not exactly understand what should I do and which part should I probably change.
I did some search and ina web-site somebody told if we define the array like this, the overflow error will be removed.
uint8_t buffer2[64000] __attribute__((section(".ccmram")));
Could you please tell me that what does it mean ? what should I do if I want to store three buffer the overall size of which are around 500KB?
what is ccram and which part of my RAM is consisted of ccram ?
thank you.
