编程语言
首页 > 编程语言> > STM32启动代码分析及其汇编学习-ARM

STM32启动代码分析及其汇编学习-ARM

作者:互联网

STM32 启动代码

Author By YuCloud

边看启动文件边学汇编

汇编

see ARM: Assembler User Guide

see: https://blog.csdn.net/zlmm741/article/details/105189487

指令 作用
EQU 取符号名(类似C #define),同义词 *
AREA 指示编译器汇编一个新段(代码段或数据段)
SPACE 分配内存空间并填零。[标号] SPACE [表达式], 同义词 %
PRESERVE8 按8字节对齐
EXPORT 声明全局,可被外部文件使用,同义词 GLOBAL
DCD 以字为单位分配内存,要求4字节对齐且初始化该内存
PROC 定义子程序,与ENDP成对使用,表示子程序结束 同义词 FUNCTION
WEAK 编译器特性。弱定义,优先使用外部文件定义的标号。
IMPORT 声明标号来自外部文件,类似于C extern
B 跳转到一个标号
ALIGN 编译器指令,对指令或数据存放地址进行对齐(一般跟一个立即数,缺省为4字节)
END EOF,文件结束
IF,ELSE,ENDIF 条件分支

STM32 启动文件详解

注意,汇编里的注释符是;,但这里为了视觉效果,用了斜杆

Stack_Size EQU 0x00000400 		// 定义一个符号,0x400为1KB	
    
// 汇编一个新段,名为STACK 不初始化(即不填零) 可读可写 2^3=8字节对齐
            AREA STACK, NOINIT, READWRITE, ALIGN=3 
    
  
Stack_Mem SPACE Stack_Size  // 栈本体,这里指令是分配栈大小  
__initial_sp				// 标名, 表示该地址(这里是末尾,即栈顶地址) 
    

也就是 通知编译器链接 -> 分配一片栈空间 -> 记录栈顶地址

栈的作用是用于局部变量,函数调用,函数形参等的开销,栈的大小不能超过内部SRAM的大小。如果编写的程序比较大,定义的局部变量很多,那么就需要修改栈的大小。如果某一天,你写的程序出现了莫名奇怪的错误,并进入了硬 fault 的时候,这时你就要考虑下是不是栈不够大,溢出了。

指令详解

image-20210815235610050

SPACE 指令用于留出一段填零的内存空间

初始化是指

Indicates that the data section is uninitialized, or initialized to zero.

image-20210816002155079

指令文档链接:EQUSPACEAREA

EQU 是伪指令,不生成二进制代码

另外,Label 就是一个标号,加不加只是为了规范,不影响二进制结果。其实上面代码等价于

AREA STACK, NOINIT, READWRITE, ALIGN=3  
SPACE 0x00000400 // 栈本体,这里指令是分配栈大小  
<编译器拿到__initial_sp所在行编译时的地址>	//标名, 表示该地址(这里是末尾,即栈顶地址) 

对了,官方文档说 Use the ALIGN directive to align any code following a SPACE or FILL directive.

ALIGN 指令对齐 SPACE FILL 指令之后的任何代码,而AREA 里有 ALIGN 参数

个人猜测: AREASPACE 配合,才能生成一个段

反汇编一个程序,段是这样的(黑色箭头是 段名,方框是 整个段的内容)

image-20210816005104654

Heap_Size EQU 0x00000200 		//Heap_Size=512B
		    // 新段,名为HEAP,可读可写,不初始化,8B对齐
            AREA HEAP, NOINIT, READWRITE, ALIGN=3 	
    
__heap_base 				// 堆的起始地址
Heap_Mem SPACE Heap_Size 	// 堆本体
__heap_limit				// 堆的结束地址

堆用于 malloc/calloc 等用于动态分配内存的函数

通知编译器链接->记录堆头地址->分配一片堆空间->记录堆尾地址

静态变量和局部变量都是在SRAM中分配

过渡

PRESERVE8 	// 指定当前文件的栈按 8B 对齐
THUMB		// 表示后面的指令兼容 Thumb 指令集(ARM以前的16位指令集)

image-20210816010301556

向量表

AREA RESET, DATA, READONLY // 汇编新段,名为RESET的数据段,只读
EXPORT __Vectors 			//向量表起始
EXPORT __Vectors_End 		//向量表末尾
EXPORT __Vectors_Size 		//向量表大小,可由__Vectors_End-__Vectors计算

__Vectors 
		DCD __initial_sp
    	DCD Reset_Handler
    	DCD NMI_Handler
		// ... 省略一些代
    	DCD DMA2D_IRQHandler
__Vectors_End  

__Vectors_Size EQU     __Vectors_End - __Vectors
    

EXPORT/GLOBAL 声明全局,可被外部文件使用

image-20210816010941865

向量表作用:

当内核响应了一个发生的异常后,对应的异常服务例程(ESR)就会执行。为了决定 ESR的入口地址, 内核使用了―向量表查表机制‖。这里使用一张向量表。向量表其实是一个WORD(32 位整数)数组,每个下标对应一种异常,该下标元素的值则是该 ESR 的入口地址。向量表在地址空间中的位置是可以设置的,通过 NVIC 中的一个重定位寄存器来指出向量表的地址。

在复位后,该寄存器的值为 0。因此,在地址 0 (即 FLASH 地址 0) 处必须包含一张向量表,用于初始时的异常分配。要注意的是这里有个另类: 0 号类型并不是什么入口地址,而是给出了复位后 MSP 的初值。

向量表从 FLASH 的 0 地址开始放置,以 4 个字节为一个单位,地址 0 存放的是栈顶地址, 0X04 存放的是复位程序的地址,以此类推。从代码上看,向量表中存放的都是中断服务函数的函数名,可我们知道 C 语言中的函数名就是一个地址。

DCD:分配一个或者多个以字为单位的内存,以四字节对齐,并要求初始化这些内存。在向量表中, DCD 分配了一堆内存,并且以 ESR 的入口地址初始化它们。

用人话说: 内核在异常时会访问这个表地址,并根据异常类型查表,按表跳转到异常处理函数执行。

各种中断处理程序 xxx_Handler

先指示编译器汇编一个新的代码段,名为 |.text|,只读

                AREA    |.text|, CODE, READONLY
复位程序,也就是默认上电复位后执行的程序
; Reset handler
Reset_Handler    PROC
                 EXPORT  Reset_Handler             [WEAK]
        IMPORT  SystemInit
        IMPORT  __main

                 LDR     R0, =SystemInit
                 BLX     R0
                 LDR     R0, =__main
                 BX      R0
                 ENDP

弱符号导出本程序Reset_Handler,导入 SystemInit__main 两个符号,并LDR数据到R0寄存器,跳转执行(BLX/BX)

注:R0~R3 寄存器通常用于函数入参出参或子程序调用,详细请自行搜索 ARM 寄存器作用

PORC 标记了程序的开始,ENDP 标记了程序的末尾。与R13(SP)寄存器相关。

R13(即SP栈指针寄存器): 当程序的运行进入异常模式时,可以将需要保护的寄存器放入R13所指向的堆栈,而当程序从异常模式返回时,则从对应的堆栈中恢复,采用这种方式可以保证异常发生后程序的正常执行。

B 跳转的都是相对地址(相对于 PC寄存器),偏移值是由编译器计算的

B {条件} 目标地址 条件可选,立即跳转执行。(不返回程序),B . 是死循环while(1);的用法

BL 目标地址 无条件跳转到目标地址处执行,并保存PC值到 R14(LR) 寄存器

BLX 目标地址 无条件跳转到目标地址处执行,并切换工作状态为 Thumb ,同时保存PC值到 R14(LR) 寄存器

子程序返回:通过将 R14 寄存器值复制到 PC 来实现。

前文说到, Label 代表的就是其所在地址

其他异常处理程序
定义异常处理子程序
; Dummy Exception Handlers (infinite loops which can be modified)

NMI_Handler     PROC
                EXPORT  NMI_Handler                [WEAK]
                B       .
                ENDP
HardFault_Handler\
                PROC
                EXPORT  HardFault_Handler          [WEAK]
                B       .
                ENDP
    		//...省略一些
SysTick_Handler PROC
                EXPORT  SysTick_Handler            [WEAK]
                B       .
                ENDP    

这里虽然有 B . (跳转到当前地址执行,这里会不断跳转执行 B .,也就是死循环),

但是有外部 xxx_Handler时,应该是会返回异常之前的处理函数的,所以在有处理函数的情况下,不会死循环,而是执行完异常处理函数后再跳回异常之前的函数。

弱导出 异常处理函数 的符号表
Default_Handler PROC

                EXPORT  WWDG_IRQHandler                   [WEAK]                                 EXPORT  PVD_IRQHandler                    [WEAK]       
    
    			// 省略一些
    			EXPORT  FPU_IRQHandler                    [WEAK]
                EXPORT  SPI4_IRQHandler                   [WEAK]
    

这里 [WEAK] 表示优先使用外部符号,如果没有才使用内部的(即刚才上面定义的子程序)

中断处理函数的符号表

这里是标号,也就是表明程序地址在这里

这样就排列出了中断处理函数表,顺序必须和前面的符号表对应,

应该就是为了让编译器对着符号名链接子程序?

WWDG_IRQHandler                                                       
PVD_IRQHandler                                      
TAMP_STAMP_IRQHandler                  
RTC_WKUP_IRQHandler                                
FLASH_IRQHandler    
//...省略一些  
FPU_IRQHandler
SPI4_IRQHandler 
   

// 死循环(点表示当前地址,B表示立即跳转)应该是防止程序跑飞,,所以一切执行完成后就在这里死循环
                B       .

// 程序的结束符
                ENDP
// 对齐(默认4B对齐
                ALIGN
堆栈初始化
;*******************************************************************************
; User Stack and Heap initialization
;*******************************************************************************
                 IF      :DEF:__MICROLIB
                
                 EXPORT  __initial_sp
                 EXPORT  __heap_base
                 EXPORT  __heap_limit
                
                 ELSE
                
                 IMPORT  __use_two_region_memory  //
                 EXPORT  __user_initial_stackheap //导出了

__user_initial_stackheap 的程序定义: 保存堆栈地址和大小到寄存器

// 下面是 __user_initial_stackheap 的程序定义,用于导出给外部程序调用的
__user_initial_stackheap

                 LDR     R0, =  Heap_Mem
                 LDR     R1, =(Stack_Mem + Stack_Size)
                 LDR     R2, = (Heap_Mem +  Heap_Size)
                 LDR     R3, = Stack_Mem
                 BX      LR

                 ALIGN

                 ENDIF

                 END

;************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE*****

启动文件代码(startup_stm32f401xx.s)

点击展开完整代码 [startup_stm32f401xx.s]
;******************** (C) COPYRIGHT 2014 STMicroelectronics ********************
;* File Name          : startup_stm32f401xx.s
;* Author             : MCD Application Team
;* @version           : V1.4.0
;* @date              : 04-August-2014
;* Description        : STM32F401xx devices vector table for MDK-ARM toolchain. 
;*                      This module performs:
;*                      - Set the initial SP
;*                      - Set the initial PC == Reset_Handler
;*                      - Set the vector table entries with the exceptions ISR address
;*                      - Configure the system clock
;*                      - Branches to __main in the C library (which eventually
;*                        calls main()).
;*                      After Reset the CortexM4 processor is in Thread mode,
;*                      priority is Privileged, and the Stack is set to Main.
;* <<< Use Configuration Wizard in Context Menu >>>   
;*******************************************************************************
; 
; Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
; You may not use this file except in compliance with the License.
; You may obtain a copy of the License at:
; 
;        http://www.st.com/software_license_agreement_liberty_v2
; 
; Unless required by applicable law or agreed to in writing, software 
; distributed under the License is distributed on an "AS IS" BASIS, 
; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
; See the License for the specific language governing permissions and
; limitations under the License.
; 
;*******************************************************************************

; Amount of memory (in bytes) allocated for Stack
; Tailor this value to your application needs
; <h> Stack Configuration
;   <o> Stack Size (in Bytes) <0x0-0xFFFFFFFF:8>
; </h>

Stack_Size      EQU     0x00000400

                AREA    STACK, NOINIT, READWRITE, ALIGN=3
Stack_Mem       SPACE   Stack_Size
__initial_sp


; <h> Heap Configuration
;   <o>  Heap Size (in Bytes) <0x0-0xFFFFFFFF:8>
; </h>

Heap_Size       EQU     0x00000200

                AREA    HEAP, NOINIT, READWRITE, ALIGN=3
__heap_base
Heap_Mem        SPACE   Heap_Size
__heap_limit

                PRESERVE8
                THUMB


; Vector Table Mapped to Address 0 at Reset
                AREA    RESET, DATA, READONLY
                EXPORT  __Vectors
                EXPORT  __Vectors_End
                EXPORT  __Vectors_Size

__Vectors       DCD     __initial_sp               ; Top of Stack
                DCD     Reset_Handler              ; Reset Handler
                DCD     NMI_Handler                ; NMI Handler
                DCD     HardFault_Handler          ; Hard Fault Handler
                DCD     MemManage_Handler          ; MPU Fault Handler
                DCD     BusFault_Handler           ; Bus Fault Handler
                DCD     UsageFault_Handler         ; Usage Fault Handler
                DCD     0                          ; Reserved
                DCD     0                          ; Reserved
                DCD     0                          ; Reserved
                DCD     0                          ; Reserved
                DCD     SVC_Handler                ; SVCall Handler
                DCD     DebugMon_Handler           ; Debug Monitor Handler
                DCD     0                          ; Reserved
                DCD     PendSV_Handler             ; PendSV Handler
                DCD     SysTick_Handler            ; SysTick Handler

                ; External Interrupts
                DCD     WWDG_IRQHandler                   ; Window WatchDog                                        
                DCD     PVD_IRQHandler                    ; PVD through EXTI Line detection                        
                DCD     TAMP_STAMP_IRQHandler             ; Tamper and TimeStamps through the EXTI line            
                DCD     RTC_WKUP_IRQHandler               ; RTC Wakeup through the EXTI line                       
                DCD     FLASH_IRQHandler                  ; FLASH                                           
                DCD     RCC_IRQHandler                    ; RCC                                             
                DCD     EXTI0_IRQHandler                  ; EXTI Line0                                             
                DCD     EXTI1_IRQHandler                  ; EXTI Line1                                             
                DCD     EXTI2_IRQHandler                  ; EXTI Line2                                             
                DCD     EXTI3_IRQHandler                  ; EXTI Line3                                             
                DCD     EXTI4_IRQHandler                  ; EXTI Line4                                             
                DCD     DMA1_Stream0_IRQHandler           ; DMA1 Stream 0                                   
                DCD     DMA1_Stream1_IRQHandler           ; DMA1 Stream 1                                   
                DCD     DMA1_Stream2_IRQHandler           ; DMA1 Stream 2                                   
                DCD     DMA1_Stream3_IRQHandler           ; DMA1 Stream 3                                   
                DCD     DMA1_Stream4_IRQHandler           ; DMA1 Stream 4                                   
                DCD     DMA1_Stream5_IRQHandler           ; DMA1 Stream 5                                   
                DCD     DMA1_Stream6_IRQHandler           ; DMA1 Stream 6                                   
                DCD     ADC_IRQHandler                    ; ADC1                            
                DCD     0                                 ; Reserved                                               
                DCD     0                                 ; Reserved                                               
                DCD     0                                 ; Reserved                                                
                DCD     0                                 ; Reserved                                               
                DCD     EXTI9_5_IRQHandler                ; External Line[9:5]s                                    
                DCD     TIM1_BRK_TIM9_IRQHandler          ; TIM1 Break and TIM9                   
                DCD     TIM1_UP_TIM10_IRQHandler          ; TIM1 Update and TIM10                 
                DCD     TIM1_TRG_COM_TIM11_IRQHandler     ; TIM1 Trigger and Commutation and TIM11
                DCD     TIM1_CC_IRQHandler                ; TIM1 Capture Compare                                   
                DCD     TIM2_IRQHandler                   ; TIM2                                            
                DCD     TIM3_IRQHandler                   ; TIM3                                            
                DCD     TIM4_IRQHandler                   ; TIM4                                            
                DCD     I2C1_EV_IRQHandler                ; I2C1 Event                                             
                DCD     I2C1_ER_IRQHandler                ; I2C1 Error                                             
                DCD     I2C2_EV_IRQHandler                ; I2C2 Event                                             
                DCD     I2C2_ER_IRQHandler                ; I2C2 Error                                               
                DCD     SPI1_IRQHandler                   ; SPI1                                            
                DCD     SPI2_IRQHandler                   ; SPI2                                            
                DCD     USART1_IRQHandler                 ; USART1                                          
                DCD     USART2_IRQHandler                 ; USART2                                          
                DCD     0                                 ; Reserved                                           
                DCD     EXTI15_10_IRQHandler              ; External Line[15:10]s                                  
                DCD     RTC_Alarm_IRQHandler              ; RTC Alarm (A and B) through EXTI Line                  
                DCD     OTG_FS_WKUP_IRQHandler            ; USB OTG FS Wakeup through EXTI line                        
                DCD     0                                 ; Reserved                   
                DCD     0                                 ; Reserved                  
                DCD     0                                 ; Reserved 
                DCD     0                                 ; Reserved                                    
                DCD     DMA1_Stream7_IRQHandler           ; DMA1 Stream7                                           
                DCD     0                                 ; Reserved                                             
                DCD     SDIO_IRQHandler                   ; SDIO                                            
                DCD     TIM5_IRQHandler                   ; TIM5                                            
                DCD     SPI3_IRQHandler                   ; SPI3                                            
                DCD     0                                 ; Reserved                                           
                DCD     0                                 ; Reserved                                            
                DCD     0                                 ; Reserved                   
                DCD     0                                 ; Reserved                   
                DCD     DMA2_Stream0_IRQHandler           ; DMA2 Stream 0                                   
                DCD     DMA2_Stream1_IRQHandler           ; DMA2 Stream 1                                   
                DCD     DMA2_Stream2_IRQHandler           ; DMA2 Stream 2                                   
                DCD     DMA2_Stream3_IRQHandler           ; DMA2 Stream 3                                   
                DCD     DMA2_Stream4_IRQHandler           ; DMA2 Stream 4                                   
                DCD     0                                 ; Reserved                                         
                DCD     0                                 ; Reserved                      
                DCD     0                                 ; Reserved                                              
                DCD     0                                 ; Reserved                                               
                DCD     0                                 ; Reserved                                               
                DCD     0                                 ; Reserved                                              
                DCD     OTG_FS_IRQHandler                 ; USB OTG FS                                      
                DCD     DMA2_Stream5_IRQHandler           ; DMA2 Stream 5                                   
                DCD     DMA2_Stream6_IRQHandler           ; DMA2 Stream 6                                   
                DCD     DMA2_Stream7_IRQHandler           ; DMA2 Stream 7                                   
                DCD     USART6_IRQHandler                 ; USART6                                           
                DCD     I2C3_EV_IRQHandler                ; I2C3 event                                             
                DCD     I2C3_ER_IRQHandler                ; I2C3 error                                             
                DCD     0                                 ; Reserved                       
                DCD     0                                 ; Reserved                       
                DCD     0                                 ; Reserved                        
                DCD     0                                 ; Reserved                                      
                DCD     0                                 ; Reserved                                            
                DCD     0                                 ; Reserved                                     
                DCD     0                                 ; Reserved 
                DCD     FPU_IRQHandler                    ; FPU
                DCD     0                                 ; Reserved  
                DCD     0                                 ; Reserved  
                DCD     SPI4_IRQHandler                   ; SPI4
                                         
__Vectors_End

__Vectors_Size  EQU  __Vectors_End - __Vectors

                AREA    |.text|, CODE, READONLY

; Reset handler
Reset_Handler    PROC
                 EXPORT  Reset_Handler             [WEAK]
        IMPORT  SystemInit
        IMPORT  __main

                 LDR     R0, =SystemInit
                 BLX     R0
                 LDR     R0, =__main
                 BX      R0
                 ENDP

; Dummy Exception Handlers (infinite loops which can be modified)

NMI_Handler     PROC
                EXPORT  NMI_Handler                [WEAK]
                B       .
                ENDP
HardFault_Handler\
                PROC
                EXPORT  HardFault_Handler          [WEAK]
                B       .
                ENDP
MemManage_Handler\
                PROC
                EXPORT  MemManage_Handler          [WEAK]
                B       .
                ENDP
BusFault_Handler\
                PROC
                EXPORT  BusFault_Handler           [WEAK]
                B       .
                ENDP
UsageFault_Handler\
                PROC
                EXPORT  UsageFault_Handler         [WEAK]
                B       .
                ENDP
SVC_Handler     PROC
                EXPORT  SVC_Handler                [WEAK]
                B       .
                ENDP
DebugMon_Handler\
                PROC
                EXPORT  DebugMon_Handler           [WEAK]
                B       .
                ENDP
PendSV_Handler  PROC
                EXPORT  PendSV_Handler             [WEAK]
                B       .
                ENDP
SysTick_Handler PROC
                EXPORT  SysTick_Handler            [WEAK]
                B       .
                ENDP

Default_Handler PROC

                EXPORT  WWDG_IRQHandler                   [WEAK]                                        
                EXPORT  PVD_IRQHandler                    [WEAK]                      
                EXPORT  TAMP_STAMP_IRQHandler             [WEAK]         
                EXPORT  RTC_WKUP_IRQHandler               [WEAK]                     
                EXPORT  FLASH_IRQHandler                  [WEAK]                                         
                EXPORT  RCC_IRQHandler                    [WEAK]                                            
                EXPORT  EXTI0_IRQHandler                  [WEAK]                                            
                EXPORT  EXTI1_IRQHandler                  [WEAK]                                             
                EXPORT  EXTI2_IRQHandler                  [WEAK]                                            
                EXPORT  EXTI3_IRQHandler                  [WEAK]                                           
                EXPORT  EXTI4_IRQHandler                  [WEAK]                                            
                EXPORT  DMA1_Stream0_IRQHandler           [WEAK]                                
                EXPORT  DMA1_Stream1_IRQHandler           [WEAK]                                   
                EXPORT  DMA1_Stream2_IRQHandler           [WEAK]                                   
                EXPORT  DMA1_Stream3_IRQHandler           [WEAK]                                   
                EXPORT  DMA1_Stream4_IRQHandler           [WEAK]                                   
                EXPORT  DMA1_Stream5_IRQHandler           [WEAK]                                   
                EXPORT  DMA1_Stream6_IRQHandler           [WEAK]                                   
                EXPORT  ADC_IRQHandler                    [WEAK]                                                                        
                EXPORT  EXTI9_5_IRQHandler                [WEAK]                                    
                EXPORT  TIM1_BRK_TIM9_IRQHandler          [WEAK]                  
                EXPORT  TIM1_UP_TIM10_IRQHandler          [WEAK]                
                EXPORT  TIM1_TRG_COM_TIM11_IRQHandler     [WEAK] 
                EXPORT  TIM1_CC_IRQHandler                [WEAK]                                   
                EXPORT  TIM2_IRQHandler                   [WEAK]                                            
                EXPORT  TIM3_IRQHandler                   [WEAK]                                            
                EXPORT  TIM4_IRQHandler                   [WEAK]                                            
                EXPORT  I2C1_EV_IRQHandler                [WEAK]                                             
                EXPORT  I2C1_ER_IRQHandler                [WEAK]                                             
                EXPORT  I2C2_EV_IRQHandler                [WEAK]                                            
                EXPORT  I2C2_ER_IRQHandler                [WEAK]                                               
                EXPORT  SPI1_IRQHandler                   [WEAK]                                           
                EXPORT  SPI2_IRQHandler                   [WEAK]                                            
                EXPORT  USART1_IRQHandler                 [WEAK]                                          
                EXPORT  USART2_IRQHandler                 [WEAK]                                                                                  
                EXPORT  EXTI15_10_IRQHandler              [WEAK]                                  
                EXPORT  RTC_Alarm_IRQHandler              [WEAK]                  
                EXPORT  OTG_FS_WKUP_IRQHandler            [WEAK]                                                                          
                EXPORT  DMA1_Stream7_IRQHandler           [WEAK]                                                                                     
                EXPORT  SDIO_IRQHandler                   [WEAK]                                             
                EXPORT  TIM5_IRQHandler                   [WEAK]                                             
                EXPORT  SPI3_IRQHandler                   [WEAK]                                                                                                           
                EXPORT  DMA2_Stream0_IRQHandler           [WEAK]                                  
                EXPORT  DMA2_Stream1_IRQHandler           [WEAK]                                   
                EXPORT  DMA2_Stream2_IRQHandler           [WEAK]                                    
                EXPORT  DMA2_Stream3_IRQHandler           [WEAK]                                    
                EXPORT  DMA2_Stream4_IRQHandler           [WEAK]                                                                             
                EXPORT  OTG_FS_IRQHandler                 [WEAK]                                       
                EXPORT  DMA2_Stream5_IRQHandler           [WEAK]                                   
                EXPORT  DMA2_Stream6_IRQHandler           [WEAK]                                   
                EXPORT  DMA2_Stream7_IRQHandler           [WEAK]                                   
                EXPORT  USART6_IRQHandler                 [WEAK]                                           
                EXPORT  I2C3_EV_IRQHandler                [WEAK]                                              
                EXPORT  I2C3_ER_IRQHandler                [WEAK]                                              
                EXPORT  FPU_IRQHandler                    [WEAK]
                EXPORT  SPI4_IRQHandler                   [WEAK]

WWDG_IRQHandler                                                       
PVD_IRQHandler                                      
TAMP_STAMP_IRQHandler                  
RTC_WKUP_IRQHandler                                
FLASH_IRQHandler                                                       
RCC_IRQHandler                                                            
EXTI0_IRQHandler                                                          
EXTI1_IRQHandler                                                           
EXTI2_IRQHandler                                                          
EXTI3_IRQHandler                                                         
EXTI4_IRQHandler                                                          
DMA1_Stream0_IRQHandler                                       
DMA1_Stream1_IRQHandler                                          
DMA1_Stream2_IRQHandler                                          
DMA1_Stream3_IRQHandler                                          
DMA1_Stream4_IRQHandler                                          
DMA1_Stream5_IRQHandler                                          
DMA1_Stream6_IRQHandler                                          
ADC_IRQHandler                                                                                                 
EXTI9_5_IRQHandler                                                
TIM1_BRK_TIM9_IRQHandler                        
TIM1_UP_TIM10_IRQHandler                      
TIM1_TRG_COM_TIM11_IRQHandler  
TIM1_CC_IRQHandler                                               
TIM2_IRQHandler                                                           
TIM3_IRQHandler                                                           
TIM4_IRQHandler                                                           
I2C1_EV_IRQHandler                                                         
I2C1_ER_IRQHandler                                                         
I2C2_EV_IRQHandler                                                        
I2C2_ER_IRQHandler                                                           
SPI1_IRQHandler                                                          
SPI2_IRQHandler                                                           
USART1_IRQHandler                                                       
USART2_IRQHandler                                                                                                             
EXTI15_10_IRQHandler                                            
RTC_Alarm_IRQHandler                            
OTG_FS_WKUP_IRQHandler                                                                             
DMA1_Stream7_IRQHandler                                                                                                            
SDIO_IRQHandler                                                            
TIM5_IRQHandler                                                            
SPI3_IRQHandler                                                                                                                                                   
DMA2_Stream0_IRQHandler                                         
DMA2_Stream1_IRQHandler                                          
DMA2_Stream2_IRQHandler                                           
DMA2_Stream3_IRQHandler                                           
DMA2_Stream4_IRQHandler                                        
ETH_IRQHandler                                                                                                                  
OTG_FS_IRQHandler                                                    
DMA2_Stream5_IRQHandler                                          
DMA2_Stream6_IRQHandler                                          
DMA2_Stream7_IRQHandler                                          
USART6_IRQHandler                                                        
I2C3_EV_IRQHandler                                                          
I2C3_ER_IRQHandler                                                          
FPU_IRQHandler
SPI4_IRQHandler 
   
                B       .

                ENDP

                ALIGN

;*******************************************************************************
; User Stack and Heap initialization
;*******************************************************************************
                 IF      :DEF:__MICROLIB
                
                 EXPORT  __initial_sp
                 EXPORT  __heap_base
                 EXPORT  __heap_limit
                
                 ELSE
                
                 IMPORT  __use_two_region_memory
                 EXPORT  __user_initial_stackheap
                 
__user_initial_stackheap

                 LDR     R0, =  Heap_Mem
                 LDR     R1, =(Stack_Mem + Stack_Size)
                 LDR     R2, = (Heap_Mem +  Heap_Size)
                 LDR     R3, = Stack_Mem
                 BX      LR

                 ALIGN

                 ENDIF

                 END

;************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE*****

标签:__,汇编,IRQHandler,DCD,WEAK,STM32,Handler,EXPORT,ARM
来源: https://www.cnblogs.com/yucloud/p/stm32_startup.html