How to use “attribute” in STM32CubeIDE
前言
attribute__的作用就是將變量或者數組存在指定的地址。在實際應用中一般將程序的版本信息固定在特定的flash地址。這邊因要協助修改讓Hex燒入檔案能可以認到版本資訊，但嚐試使用STM32CcubeIDE後發現，無法使用，但KEIL卻是正常的，找尋網路方式但都試不出來會出現錯誤，最後發現正確使用方式
修改ld文件
這邊因為STM32CubeIDE這邊在Flash LD檔與KEIL方式不同，因此如果需要使用“attribute”這一快是需要修正的
第一步需要先在主MEMORY那邊宣告你所需要使用區塊
/* Memories definition */
MEMORY
{
RAM (xrw) : ORIGIN = 0x20000000, LENGTH = 96K
FLASH (rx) : ORIGIN = 0x8000000, LENGTH = 512K
Version (rx) : ORIGIN =0x0806B000, LENGTH = 1K
}
第二步是在/* Sections */內部新增
在繼續在ld文件的下面進行修改。這裡就要特別注意了。
.VERSION :
{
KEEP(*(.MCU_version))
} >Version
.VERSION : 是在main函數之前定義的數組的名字。
KEEP(*(.MCU_version))是main函數之前定義的section（）中的名字。
Version尖括號後的是在前面的ld文件中添加的。
到這裡 ，就能正常編譯了。
在main.c內使用如下(需要宣告在main loop外)
unsigned int Version[2] __attribute__((section(".MCU_version"))) = {0x051E0817,0x00020101};
結果圖如下可以看到最下面多出設定位置與數值
LD檔完整附錄
/*
******************************************************************************
**
** @file : LinkerScript.ld
**
** @author : Auto-generated by STM32CubeIDE
**
** Abstract : Linker script for NUCLEO-F401RE Board embedding STM32F401RETx Device from stm32f4 series
** 512KBytes FLASH
** 96KBytes 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) 2023 STMicroelectronics.
** All rights reserved.
**
** This software is licensed under terms that can be found in the LICENSE file
** in the root directory of this software component.
** If no LICENSE file comes with this software, it is provided AS-IS.
**
******************************************************************************
*/
/* Entry Point */
ENTRY(Reset_Handler)
/* Highest address of the user mode stack */
_estack = ORIGIN(RAM) + LENGTH(RAM); /* end of "RAM" Ram type memory */
_Min_Heap_Size = 0x200; /* required amount of heap */
_Min_Stack_Size = 0x400; /* required amount of stack */
/* Memories definition */
MEMORY
{
RAM (xrw) : ORIGIN = 0x20000000, LENGTH = 96K
FLASH (rx) : ORIGIN = 0x8000000, LENGTH = 512K
Version (rx) : ORIGIN =0x0806B000, LENGTH = 1K
}
/* Sections */
SECTIONS
{
/* The startup code into "FLASH" Rom type memory */
.isr_vector :
{
. = ALIGN(4);
KEEP(*(.isr_vector)) /* Startup code */
. = ALIGN(4);
} >FLASH
/* The program code and other data into "FLASH" Rom type memory */
.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 */
} >FLASH
/* Constant data into "FLASH" Rom type memory */
.rodata :
{
. = ALIGN(4);
*(.rodata) /* .rodata sections (constants, strings, etc.) */
*(.rodata*) /* .rodata* sections (constants, strings, etc.) */
. = ALIGN(4);
} >FLASH
.ARM.extab : {
. = ALIGN(4);
*(.ARM.extab* .gnu.linkonce.armextab.*)
. = ALIGN(4);
} >FLASH
.ARM : {
. = ALIGN(4);
__exidx_start = .;
*(.ARM.exidx*)
__exidx_end = .;
. = ALIGN(4);
} >FLASH
.preinit_array :
{
. = ALIGN(4);
PROVIDE_HIDDEN (__preinit_array_start = .);
KEEP (*(.preinit_array*))
PROVIDE_HIDDEN (__preinit_array_end = .);
. = ALIGN(4);
} >FLASH
.init_array :
{
. = ALIGN(4);
PROVIDE_HIDDEN (__init_array_start = .);
KEEP (*(SORT(.init_array.*)))
KEEP (*(.init_array*))
PROVIDE_HIDDEN (__init_array_end = .);
. = ALIGN(4);
} >FLASH
.fini_array :
{
. = ALIGN(4);
PROVIDE_HIDDEN (__fini_array_start = .);
KEEP (*(SORT(.fini_array.*)))
KEEP (*(.fini_array*))
PROVIDE_HIDDEN (__fini_array_end = .);
. = ALIGN(4);
} >FLASH
.VERSION :
{
KEEP(*(.MCU_version))
} >Version
/* Used by the startup to initialize data */
_sidata = LOADADDR(.data);
/* Initialized data sections into "RAM" Ram type memory */
.data :
{
. = ALIGN(4);
_sdata = .; /* create a global symbol at data start */
*(.data) /* .data sections */
*(.data*) /* .data* sections */
*(.RamFunc) /* .RamFunc sections */
*(.RamFunc*) /* .RamFunc* sections */
. = ALIGN(4);
_edata = .; /* define a global symbol at data end */
} >RAM AT> FLASH
/* Uninitialized data section into "RAM" Ram type memory */
. = ALIGN(4);
.bss :
{
/* This is used by the startup in order to initialize the .bss section */
_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" Ram type memory left */
._user_heap_stack :
{
. = ALIGN(8);
PROVIDE ( end = . );
PROVIDE ( _end = . );
. = . + _Min_Heap_Size;
. = . + _Min_Stack_Size;
. = ALIGN(8);
} >RAM
/* Remove information from the compiler libraries */
/DISCARD/ :
{
libc.a ( * )
libm.a ( * )
libgcc.a ( * )
}
.ARM.attributes 0 : { *(.ARM.attributes) }
}