STM32 keil mdk 启动代码分析
1 ;// <h> Stack Configuration
2 ;// <o> Stack Size (in Bytes) <0x0-0xFFFFFFFF:8>
3 ;// </h>
4 Stack_Size EQU 0x00000200 ;//定义堆栈大小
5 AREA STACK, NOINIT, READWRITE, ALIGN=3 ;//定义一个数据段 按8字节对齐
6 Stack_Mem SPACE Stack_Size ;//保留Stack_Size大小的堆栈空间
7 __initial_sp ;//标号，代表堆栈顶部地址，后面有用
8
9 ;// <h> Heap Configuration
10 ;// <o> Heap Size (in Bytes) <0x0-0xFFFFFFFF:8>
11 ;// </h>
12 Heap_Size EQU 0x00000020 ;//定义堆空间大小
13 AREA HEAP, NOINIT, READWRITE, ALIGN=3 ;//定义一个数据段，8字节对齐
14 __heap_base
15 Heap_Mem SPACE Heap_Size ;//保留Heap_Size的堆空间
16 __heap_limit ;//标号，代表堆末尾地址，后面有用
17
18 PRESERVE8 ;//指示编译器8字节对齐
19 THUMB ;//指示编译器为THUMB指令
20
21 ; Vector Table Mapped to Address 0 at Reset
22 AREA RESET, DATA, READONLY ;//定义只读数据段，其实放在CODE区，位于0地址
23
24 EXTERN NMIException
25 EXTERN HardFaultException
26 EXTERN MemManageException
27 EXTERN BusFaultException
28 EXTERN UsageFaultException
29 EXTERN SVCHandler
30 EXTERN DebugMonitor
31 EXTERN PendSVC
32 EXTERN SysTickHandler ;//声明这些符号在外部定义，同C
33 ;//在××it.c中实现这些函数 ，中断就能自动调用了
34 EXPORT __Vectors
35 __Vectors DCD __initial_sp ; Top of Stack //Cotex-M 要求此处为堆栈顶部地址
36 DCD Reset_Handler ; Reset Handler
37 DCD NMIException ; NMI Handler
38 DCD HardFaultException ; Hard Fault Handler
39 DCD MemManageException ; MPU Fault Handler
40 DCD BusFaultException ; Bus Fault Handler
41 DCD UsageFaultException ; Usage Fault Handler
42 DCD 0 ; Reserved
43 DCD 0 ; Reserved
44 DCD 0 ; Reserved
45 DCD 0 ; Reserved
46 DCD SVCHandler ; SVCall Handler
47 DCD DebugMonitor ; Debug Monitor Handler
48 DCD 0 ; Reserved
49 DCD PendSVC ; PendSV Handler
50 DCD SysTickHandler ; SysTick Handler //一大堆的异常处理函数地址
51 ; External Interrupts
52 EXTERN WWDG_IRQHandler
53 EXTERN PVD_IRQHandler
54 EXTERN TAMPER_IRQHandler
55 EXTERN RTC_IRQHandler
56 EXTERN FLASH_IRQHandler
57 EXTERN RCC_IRQHandler
58 EXTERN EXTI0_IRQHandler
59 EXTERN EXTI1_IRQHandler
60 EXTERN EXTI2_IRQHandler
61 EXTERN EXTI3_IRQHandler
62 EXTERN EXTI4_IRQHandler
63 EXTERN DMAChannel1_IRQHandler
64 EXTERN DMAChannel2_IRQHandler
65 EXTERN DMAChannel3_IRQHandler
66 EXTERN DMAChannel4_IRQHandler
67 EXTERN DMAChannel5_IRQHandler
68 EXTERN DMAChannel6_IRQHandler
69 EXTERN DMAChannel7_IRQHandler
70 EXTERN ADC_IRQHandler
71 EXTERN USB_HP_CAN_TX_IRQHandler
72 EXTERN USB_LP_CAN_RX0_IRQHandler
73 EXTERN CAN_RX1_IRQHandler
74 EXTERN CAN_SCE_IRQHandler
75 EXTERN EXTI9_5_IRQHandler
76 EXTERN TIM1_BRK_IRQHandler
77 EXTERN TIM1_UP_IRQHandler
78 EXTERN TIM1_TRG_COM_IRQHandler
79 EXTERN TIM1_CC_IRQHandler
80 EXTERN TIM2_IRQHandler
81 EXTERN TIM3_IRQHandler
82 EXTERN TIM4_IRQHandler
83 EXTERN I2C1_EV_IRQHandler
84 EXTERN I2C1_ER_IRQHandler
85 EXTERN I2C2_EV_IRQHandler
86 EXTERN I2C2_ER_IRQHandler
87 EXTERN SPI1_IRQHandler
88 EXTERN SPI2_IRQHandler
89 EXTERN USART1_IRQHandler
90 EXTERN USART2_IRQHandler
91 EXTERN USART3_IRQHandler
92 EXTERN EXTI15_10_IRQHandler
93 EXTERN RTCAlarm_IRQHandler
94 EXTERN USBWakeUp_IRQHandler ;//同上，
95
96 DCD WWDG_IRQHandler ; Window Watchdog
97 DCD PVD_IRQHandler ; PVD through EXTI Line detect
98 DCD TAMPER_IRQHandler ; Tamper
99 DCD RTC_IRQHandler ; RTC
100 DCD FLASH_IRQHandler ; Flash
101 DCD RCC_IRQHandler ; RCC
102 DCD EXTI0_IRQHandler ; EXTI Line 0
103 DCD EXTI1_IRQHandler ; EXTI Line 1
104 DCD EXTI2_IRQHandler ; EXTI Line 2
105 DCD EXTI3_IRQHandler ; EXTI Line 3
106 DCD EXTI4_IRQHandler ; EXTI Line 4
107 DCD DMAChannel1_IRQHandler ; DMA Channel 1
108 DCD DMAChannel2_IRQHandler ; DMA Channel 2
109 DCD DMAChannel3_IRQHandler ; DMA Channel 3
110 DCD DMAChannel4_IRQHandler ; DMA Channel 4
111 DCD DMAChannel5_IRQHandler ; DMA Channel 5
112 DCD DMAChannel6_IRQHandler ; DMA Channel 6
113 DCD DMAChannel7_IRQHandler ; DMA Channel 7
114 DCD ADC_IRQHandler ; ADC
115 DCD USB_HP_CAN_TX_IRQHandler ; USB High Priority or CAN TX
116 DCD USB_LP_CAN_RX0_IRQHandler ; USB Low Priority or CAN RX0
117 DCD CAN_RX1_IRQHandler ; CAN RX1
118 DCD CAN_SCE_IRQHandler ; CAN SCE
119 DCD EXTI9_5_IRQHandler ; EXTI Line 9..5
120 DCD TIM1_BRK_IRQHandler ; TIM1 Break
121 DCD TIM1_UP_IRQHandler ; TIM1 Update
122 DCD TIM1_TRG_COM_IRQHandler ; TIM1 Trigger and Commutation
123 DCD TIM1_CC_IRQHandler ; TIM1 Capture Compare
124 DCD TIM2_IRQHandler ; TIM2
125 DCD TIM3_IRQHandler ; TIM3
126 DCD TIM4_IRQHandler ; TIM4
127 DCD I2C1_EV_IRQHandler ; I2C1 Event
128 DCD I2C1_ER_IRQHandler ; I2C1 Error
129 DCD I2C2_EV_IRQHandler ; I2C2 Event
130 DCD I2C2_ER_IRQHandler ; I2C2 Error
131 DCD SPI1_IRQHandler ; SPI1
132 DCD SPI2_IRQHandler ; SPI2
133 DCD USART1_IRQHandler ; USART1
134 DCD USART2_IRQHandler ; USART2
135 DCD USART3_IRQHandler ; USART3
136 DCD EXTI15_10_IRQHandler ; EXTI Line 15..10
137 DCD RTCAlarm_IRQHandler ; RTC Alarm through EXTI Line
138 DCD USBWakeUp_IRQHandler ; USB Wakeup from suspend ;//同上
139
140 AREA |.text|, CODE, READONLY ;//定义代码段
141
142 ; Reset Handler
143 Reset_Handler PROC ;//Rset_Handler的实现
144 EXPORT Reset_Handler [WEAK] ;//在外部没有定义该符号时导出该符号，见HELP中[WEAK]
145 IMPORT __main ;//导入符号,__main为 运行时库提供的函数；完成堆栈，堆的初始话
146 LDR R0, =__main ;//等工作，会调用下面定义的__user_initial_stackheap；
147 BX R0 ;//跳到__main，进入C的世界
148 ENDP
149
150 ALIGN
151
152 ; User Initial Stack & Heap
153 IF :DEF:__MICROLIB ;//如果使用micro lib,micro lib 描述见armlib.chm
154
155 EXPORT __initial_sp
156 EXPORT __heap_base
157 EXPORT __heap_limit ;//只导出几个定义
158
159 ELSE ;//如果使用默认C运行时库
160
161 IMPORT __use_two_region_memory
162 EXPORT __user_initial_stackheap
163 __user_initial_stackheap ;//则进行堆栈和堆的赋值，在__main函数执行过程中调用。
164 LDR R0, = Heap_Mem
165 LDR R1, =(Stack_Mem + Stack_Size)
166 LDR R2, = (Heap_Mem + Heap_Size)
167 LDR R3, = Stack_Mem
168 BX LR
169 ALIGN
170 ENDIF
171
172 END ;//OK ，完了
