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