我用的stm32官方版本3.5的固件库。单片机是STM32f103zet,所以的用的启动代码是startup_stm32f10x_hd.s。
读这个文件的时候用到了很多资料,大部分来自网络,作者不详,感谢他们。
其中知名的有,理想智芯科技的李想老师,玩转stm32的作者野火团队,感谢他们。
这是arm公司的技术支持可以用中文
http://infocenter.arm.com/help/index.jsp。
;EQU伪指令 为0x00000400取个别名Stack_Size
;Stack_Size指定栈的大小
Stack_Size
EQU
0x00000400
;AREA伪指令定义一个段STACK(栈段),属性为:NOINIT(不初始化), READWRITE(可读可写), ALIGN=3(8字
;节对齐)。
AREA
STACK, NOINIT, READWRITE, ALIGN=3
;APACE伪指令分配栈空间
;Stack_Mem变量在栈低
;__initial_sp变量的栈顶
Stack_Mem
SPACE
Stack_Size
__initial_sp
;下面代码语法同上,定义堆空间
Heap_Size
EQU
0x00000200
AREA
HEAP, NOINIT, READWRITE, ALIGN=3
__heap_base
Heap_Mem
SPACE
Heap_Size
__heap_limit
PRESERVE8 ;8字节对齐
THUMB
;用32位的Thumb指令
;定义REST段,属性DATA(数据类型),READONLY(只读)
AREA
RESET, DATA, READONLY
EXPORT
__Vectors
;输出 __Vectors变量,可以在其他文件使用
EXPORT
__Vectors_End
;输出 __Vectors_End 变量,可以在其他文件使用
EXPORT
__Vectors_Size
;输出 __Vectors_Size 变量,可以在其他文件使用
;下面代码完成中断向量的存储工作,
;DCD xxxx_xxxx 意为安字存储xxxx_xxxx变量的首地址
;__Vectors变量存储的内容为__initial_sp变量的地址
;__Vectors的地址为中断向量表的首地址
;__Vectors_End
的地址为中断向量表的结束地址地址
;__Vectors_Size 代表向量标的大小
__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 detect
DCD
TAMPER_IRQHandler
; Tamper
DCD
RTC_IRQHandler
; RTC
DCD
FLASH_IRQHandler
; Flash
DCD
RCC_IRQHandler
; RCC
DCD
EXTI0_IRQHandler
; EXTI Line 0
DCD
EXTI1_IRQHandler
; EXTI Line 1
DCD
EXTI2_IRQHandler
; EXTI Line 2
DCD
EXTI3_IRQHandler
; EXTI Line 3
DCD
EXTI4_IRQHandler
; EXTI Line 4
DCD
DMA1_Channel1_IRQHandler
; DMA1 Channel 1
DCD
DMA1_Channel2_IRQHandler
; DMA1 Channel 2
DCD
DMA1_Channel3_IRQHandler
; DMA1 Channel 3
DCD
DMA1_Channel4_IRQHandler
; DMA1 Channel 4
DCD
DMA1_Channel5_IRQHandler
; DMA1 Channel 5
DCD
DMA1_Channel6_IRQHandler
; DMA1 Channel 6
DCD
DMA1_Channel7_IRQHandler
; DMA1 Channel 7
DCD
ADC1_2_IRQHandler
; ADC1 & ADC2
DCD
USB_HP_CAN1_TX_IRQHandler
; USB High Priority or CAN1 TX
DCD
USB_LP_CAN1_RX0_IRQHandler ; USB Low
Priority or CAN1 RX0
DCD
CAN1_RX1_IRQHandler
; CAN1 RX1
DCD
CAN1_SCE_IRQHandler
; CAN1 SCE
DCD
EXTI9_5_IRQHandler
; EXTI Line 9..5
DCD
TIM1_BRK_IRQHandler
; TIM1 Break
DCD
TIM1_UP_IRQHandler
; TIM1 Update
DCD
TIM1_TRG_COM_IRQHandler
; TIM1 Trigger and Commutation
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
USART3_IRQHandler
; USART3
DCD
EXTI15_10_IRQHandler
; EXTI Line 15..10
DCD
RTCAlarm_IRQHandler
; RTC Alarm through EXTI Line
DCD
USBWakeUp_IRQHandler
; USB Wakeup from suspend
DCD
TIM8_BRK_IRQHandler
; TIM8 Break
DCD
TIM8_UP_IRQHandler
; TIM8 Update
DCD
TIM8_TRG_COM_IRQHandler
; TIM8 Trigger and Commutation
DCD
TIM8_CC_IRQHandler
; TIM8 Capture Compare
DCD
ADC3_IRQHandler
; ADC3
DCD
FSMC_IRQHandler
; FSMC
DCD
SDIO_IRQHandler
; SDIO
DCD
TIM5_IRQHandler
; TIM5
DCD
SPI3_IRQHandler
; SPI3
DCD
UART4_IRQHandler
; UART4
DCD
UART5_IRQHandler
; UART5
DCD
TIM6_IRQHandler
; TIM6
DCD
TIM7_IRQHandler
; TIM7
DCD
DMA2_Channel1_IRQHandler
; DMA2 Channel1
DCD
DMA2_Channel2_IRQHandler
; DMA2 Channel2
DCD
DMA2_Channel3_IRQHandler
; DMA2 Channel3
DCD
DMA2_Channel4_5_IRQHandler ; DMA2 Channel4 & Channel5
__Vectors_End
__Vectors_Size
EQU
__Vectors_End - __Vectors
;定义|.text|段,属性为:CODE(代码), READONLY(只读)。
;|.text|习惯性命名,表示由C编译程序产生的代码段,或用于以某种方式与C库关联的代码段
AREA
|.text|, CODE, READONLY
;下面代码相当于定义了Reset_Handler这个函数,我们通过Reset_Handler变量的地址就可以跳转过来
;由于这个段是这个文件唯一的代码段,且把main函数地址作为变量导入所以,cpu上电后会从下面程序开始
;运行。
Reset_Handler
PROC
;EXPORT
xxxx [WEAK]这句伪指令很重要。意思是说如果在其他文件中没有定义xxxx这个变量,
;那么这里定义的xxxx,1.有效,2.作为输出供其他文件中的函数调用。如果其文件定义了xxxx那么这个文件定
;义的xxxx无效。可以再arm的汇编指南中查阅到。
EXPORT
Reset_Handler
[WEAK]
;导入变量__main与SystemInit。一个是用户主程序,一个是系统时钟初始化程序
IMPORT
__main
IMPORT
SystemInit
;有返回的调用SystemInit函数,初始化系统时钟
;可以看出,在进入main函数之前,这里先初始换了系统时钟。在主函数中,就不用调用这个函数了
;SystemInit这个函数是在文件system_stm32f10x.c中实现的。system_stm32f10x.c在固件库的目录为
;STM32F10x_StdPeriph_Lib_V3.5.0LibrariesCMSISCM3DeviceSupportSTSTM32F10x
LDR
R0, =SystemInit
BLX
R0
;无返回的调用main函数,把控制全交给main函数。
LDR
R0, =__main
BX
R0
ENDP
;下面从NMI_Handler到SysTick_Handler PROC定义的是内核中断函数。
;在这里可以看出,如果用户不定义这些函数,经使用下面的定义。由伪指令EXPORT [WEAK]决定
;一定中断发生且被允许,将执行B .。这是个死循环相当于jump $
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
;下面中断函数有st给出,同样用户如果不自己定义,
;一定中断允许且发生,将进入死循环
Default_Handler PROC
EXPORT
WWDG_IRQHandler
[WEAK]
EXPORT
PVD_IRQHandler
[WEAK]
EXPORT
TAMPER_IRQHandler
[WEAK]
EXPORT
RTC_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_Channel1_IRQHandler
[WEAK]
EXPORT
DMA1_Channel2_IRQHandler
[WEAK]
EXPORT
DMA1_Channel3_IRQHandler
[WEAK]
EXPORT
DMA1_Channel4_IRQHandler
[WEAK]
EXPORT
DMA1_Channel5_IRQHandler
[WEAK]
EXPORT
DMA1_Channel6_IRQHandler
[WEAK]
EXPORT
DMA1_Channel7_IRQHandler
[WEAK]
EXPORT
ADC1_2_IRQHandler
[WEAK]
EXPORT
USB_HP_CAN1_TX_IRQHandler
[WEAK]
EXPORT
USB_LP_CAN1_RX0_IRQHandler [WEAK]
EXPORT
CAN1_RX1_IRQHandler
[WEAK]
EXPORT
CAN1_SCE_IRQHandler
[WEAK]
EXPORT
EXTI9_5_IRQHandler
[WEAK]
EXPORT
TIM1_BRK_IRQHandler
[WEAK]
EXPORT
TIM1_UP_IRQHandler
[WEAK]
EXPORT
TIM1_TRG_COM_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
USART3_IRQHandler
[WEAK]
EXPORT
EXTI15_10_IRQHandler
[WEAK]
EXPORT
RTCAlarm_IRQHandler
[WEAK]
EXPORT
USBWakeUp_IRQHandler
[WEAK]
EXPORT
TIM8_BRK_IRQHandler
[WEAK]
EXPORT
TIM8_UP_IRQHandler
[WEAK]
EXPORT
TIM8_TRG_COM_IRQHandler
[WEAK]
EXPORT
TIM8_CC_IRQHandler
[WEAK]
EXPORT
ADC3_IRQHandler
[WEAK]
EXPORT
FSMC_IRQHandler
[WEAK]
EXPORT
SDIO_IRQHandler
[WEAK]
EXPORT
TIM5_IRQHandler
[WEAK]
EXPORT
SPI3_IRQHandler
[WEAK]
EXPORT
UART4_IRQHandler
[WEAK]
EXPORT
UART5_IRQHandler
[WEAK]
EXPORT
TIM6_IRQHandler
[WEAK]
EXPORT
TIM7_IRQHandler
[WEAK]
EXPORT
DMA2_Channel1_IRQHandler
[WEAK]
EXPORT
DMA2_Channel2_IRQHandler
[WEAK]
EXPORT
DMA2_Channel3_IRQHandler
[WEAK]
EXPORT
DMA2_Channel4_5_IRQHandler [WEAK]
WWDG_IRQHandler
PVD_IRQHandler
TAMPER_IRQHandler
RTC_IRQHandler
FLASH_IRQHandler
RCC_IRQHandler
EXTI0_IRQHandler
EXTI1_IRQHandler
EXTI2_IRQHandler
EXTI3_IRQHandler
EXTI4_IRQHandler
DMA1_Channel1_IRQHandler
DMA1_Channel2_IRQHandler
DMA1_Channel3_IRQHandler
DMA1_Channel4_IRQHandler
DMA1_Channel5_IRQHandler
DMA1_Channel6_IRQHandler
DMA1_Channel7_IRQHandler
ADC1_2_IRQHandler
USB_HP_CAN1_TX_IRQHandler
USB_LP_CAN1_RX0_IRQHandler
CAN1_RX1_IRQHandler
CAN1_SCE_IRQHandler
EXTI9_5_IRQHandler
TIM1_BRK_IRQHandler
TIM1_UP_IRQHandler
TIM1_TRG_COM_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
USART3_IRQHandler
EXTI15_10_IRQHandler
RTCAlarm_IRQHandler
USBWakeUp_IRQHandler
TIM8_BRK_IRQHandler
TIM8_UP_IRQHandler
TIM8_TRG_COM_IRQHandler
TIM8_CC_IRQHandler
ADC3_IRQHandler
FSMC_IRQHandler
SDIO_IRQHandler
TIM5_IRQHandler
SPI3_IRQHandler
UART4_IRQHandler
UART5_IRQHandler
TIM6_IRQHandler
TIM7_IRQHandler
DMA2_Channel1_IRQHandler
DMA2_Channel2_IRQHandler
DMA2_Channel3_IRQHandler
DMA2_Channel4_5_IRQHandler
B
.
ENDP
ALIGN
;下面这些代码初始化堆栈。
;他们是相当复杂的,以你为我们的main和__main是不同的,__main进过编译后的main,
;编译器要对进入main做了些手脚,初始化C语言环境,其中就要堆栈。
;下面这些就是在那时候用的。可以跟踪到他们在进入main前的执行。
;当然要在disassembly先才可以看到。
;见解来自Triquinne from elecfans
;http://www.elecfans.com/emb/danpianji/20120910287921_6.html
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
好了就这么多了,上面的解释也差不多了。