;/******************************************************************************
; * @file startup_Nano100Series.s
; * @version V1.00
; * $Revision: 3 $
; * $Date: 14/01/14 4:17p $
; * @brief CMSIS ARM Cortex-M0 Core Device Startup File
; *
; * @note
; * Copyright (C) 2013 Nuvoton Technology Corp. All rights reserved.
;*****************************************************************************/
;首先對棧和堆的大小進行定義，並在代碼區的起始處建立中斷向量表，
;其第一個表項是棧頂地址，第二個表項是復位中斷服務入口地址。
;然後在復位中斷服務程序中跳轉C/C++標準實時庫的__main函數。
;復位中斷服務入口地址存放於0x0000_0000處。當M0遇到復位信號後，
;則從0x0000000處取出復位中斷服務入口地址繼而執行復位中斷服務程序
;然後跳轉__main函數，最後來到C的世界。
; <h> Stack Configuration棧配置，爲後期跳轉到C語言代碼存放參數，地址做準備
; <o> Stack Size (in Bytes) <0x0-0xFFFFFFFF:8>
; </h>
;EQU相當於C語言的define
Stack_Size EQU 0x00000500;，共1280個字節
;定義一片區域名爲STACK，未初始化段，可讀可寫，8字節對齊
AREA STACK, NOINIT, READWRITE, ALIGN=3
;此指令用於分配一片連續的存儲區域並初始化爲0。表達式爲要分配的字節數。
;SPACE可用“%”來代替
Stack_Mem SPACE Stack_Size
;__initial_sp表示一個標示,編譯器計算這個標示的地址.
__initial_sp
; <h> Heap Configuration
; <o> Heap Size (in Bytes) <0x0-0xFFFFFFFF:8>
; </h>
Heap_Size EQU 0x00000500
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
;中斷向量表映射到0x00，
AREA RESET, DATA, READONLY
;使編譯器指定一段只讀的數據段，段名爲reset
;EXPORT __Vectors
;EXPORT相當於GLOBLE關鍵字，聲明一個全局變量__vector,
;DCD指令：作用是開闢一段空間，其意義等價於C語言中的地址符“&”
;異常向量表從0x0000_0000開始，初始位置爲Stack_Point所在地，
;自動取傳入的地址存入SP寄存器中，其他中斷存放中斷程序地址，
;跳轉到ISR中執行程序，具體查看datasheet page 111中描述
__Vectors DCD __initial_sp ; Top of Stack
;取__initianl_sp地址放入0x00000000，
DCD Reset_Handler ; Reset Handler
DCD NMI_Handler ; NMI Handler
DCD HardFault_Handler ; Hard Fault Handler
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD SVC_Handler ; SVCall Handler
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD PendSV_Handler ; PendSV Handler
DCD SysTick_Handler ; SysTick Handler
; External Interrupts
DCD BOD_IRQHandler ; Brownout low voltage detected interrupt
DCD WDT_IRQHandler ; Watch Dog Timer interrupt
DCD EINT0_IRQHandler ; External signal interrupt from PB.14 pin
DCD EINT1_IRQHandler ; External signal interrupt from PB.15 pin
DCD GPABC_IRQHandler ; External interrupt from PA[15:0]/PB[15:0]/PC[15:0]
DCD GPDEF_IRQHandler ; External interrupt from PD[15:0]/PE[15:0]/PF[7:0]
DCD PWM0_IRQHandler ; PWM 0 interrupt
DCD PWM1_IRQHandler ; PWM 1 interrupt
DCD TMR0_IRQHandler ; Timer 0 interrupt
DCD TMR1_IRQHandler ; Timer 1 interrupt
DCD TMR2_IRQHandler ; Timer 2 interrupt
DCD TMR3_IRQHandler ; Timer 3 interrupt
DCD UART0_IRQHandler ; UART0 interrupt
DCD UART1_IRQHandler ; UART1 interrupt
DCD SPI0_IRQHandler ; SPI0 interrupt
DCD SPI1_IRQHandler ; SPI1 interrupt
DCD SPI2_IRQHandler ; SPI2 interrupt
DCD HIRC_IRQHandler ; HIRC interrupt
DCD I2C0_IRQHandler ; I2C0 interrupt
DCD I2C1_IRQHandler ; I2C1 interrupt
DCD SC2_IRQHandler ; SC2 interrupt
DCD SC0_IRQHandler ; SC0 interrupt
DCD SC1_IRQHandler ; SC1 interrupt
DCD USBD_IRQHandler ; USB FS Device interrupt
DCD 0 ; Reserved
DCD LCD_IRQHandler ; LCD interrupt
DCD PDMA_IRQHandler ; PDMA interrupt
DCD I2S_IRQHandler ; I2S interrupt
DCD PDWU_IRQHandler ; Power Down Wake up interrupt
DCD ADC_IRQHandler ; ADC interrupt
DCD DAC_IRQHandler ; DAC interrupt
DCD RTC_IRQHandler ; Real time clock interrupt
AREA |.text|, CODE, READONLY
; Reset Handler
;彙編僞指令PROC ENDP 提示編譯器子程序開始和結束
Reset_Handler PROC
;定義全局變量 Reset_Handle [WEAK]表示弱定義可在其他地方優先
;以便在C中調用Reset_Handle，有利於後期編寫復位程序
EXPORT Reset_Handler [WEAK]
;申明main，main在外部定義
IMPORT __main
;僞指令，提示編譯器main標示在外部定義
; 解鎖保護寄存器。向RegLockAddr連續寫入0x59,0x16,0x88解鎖
LDR R0, =0x50000100
LDR R1, =0x59
STR R1, [R0]
LDR R1, =0x16
STR R1, [R0]
LDR R1, =0x88
STR R1, [R0]
; Init POR具體看手冊，
LDR R2, =0x50000060
LDR R1, =0x00005AA5
STR R1, [R2]
; Lock register寫0，鎖住保護寄存器
MOVS R1, #0
STR R1, [R0]
LDR R0, =__main
;僞指令，將main地址存入R0中
BX R0
;跳轉到R0所在地址的位置，即__main所在程序，BX跳轉且切換指令集
ENDP
; Dummy Exception Handlers (infinite loops which can be modified)
;其他中斷入口程序，弱定義，進入死循環，以便後期C程序編寫中斷子程序
NMI_Handler PROC
EXPORT NMI_Handler [WEAK]
B .
ENDP
HardFault_Handler\;連接符
PROC
EXPORT HardFault_Handler [WEAK]
B .
ENDP
SVC_Handler PROC
EXPORT SVC_Handler [WEAK]
B .
ENDP
PendSV_Handler PROC
EXPORT PendSV_Handler [WEAK]
B .
ENDP
SysTick_Handler PROC
EXPORT SysTick_Handler [WEAK]
B .
ENDP
;缺省中斷。不寫
Default_Handler PROC
EXPORT BOD_IRQHandler [WEAK]
EXPORT WDT_IRQHandler [WEAK]
EXPORT EINT0_IRQHandler [WEAK]
EXPORT EINT1_IRQHandler [WEAK]
EXPORT GPABC_IRQHandler [WEAK]
EXPORT GPDEF_IRQHandler [WEAK]
EXPORT PWM0_IRQHandler [WEAK]
EXPORT PWM1_IRQHandler [WEAK]
EXPORT TMR0_IRQHandler [WEAK]
EXPORT TMR1_IRQHandler [WEAK]
EXPORT TMR2_IRQHandler [WEAK]
EXPORT TMR3_IRQHandler [WEAK]
EXPORT UART0_IRQHandler [WEAK]
EXPORT UART1_IRQHandler [WEAK]
EXPORT SPI0_IRQHandler [WEAK]
EXPORT SPI1_IRQHandler [WEAK]
EXPORT SPI2_IRQHandler [WEAK]
EXPORT HIRC_IRQHandler [WEAK]
EXPORT I2C0_IRQHandler [WEAK]
EXPORT I2C1_IRQHandler [WEAK]
EXPORT SC2_IRQHandler [WEAK]
EXPORT SC0_IRQHandler [WEAK]
EXPORT SC1_IRQHandler [WEAK]
EXPORT USBD_IRQHandler [WEAK]
EXPORT LCD_IRQHandler [WEAK]
EXPORT PDMA_IRQHandler [WEAK]
EXPORT I2S_IRQHandler [WEAK]
EXPORT PDWU_IRQHandler [WEAK]
EXPORT ADC_IRQHandler [WEAK]
EXPORT DAC_IRQHandler [WEAK]
EXPORT RTC_IRQHandler [WEAK]
BOD_IRQHandler
WDT_IRQHandler
EINT0_IRQHandler
EINT1_IRQHandler
GPABC_IRQHandler
GPDEF_IRQHandler
PWM0_IRQHandler
PWM1_IRQHandler
TMR0_IRQHandler
TMR1_IRQHandler
TMR2_IRQHandler
TMR3_IRQHandler
UART0_IRQHandler
UART1_IRQHandler
SPI0_IRQHandler
SPI1_IRQHandler
SPI2_IRQHandler
HIRC_IRQHandler
I2C0_IRQHandler
I2C1_IRQHandler
SC2_IRQHandler
SC0_IRQHandler
SC1_IRQHandler
USBD_IRQHandler
LCD_IRQHandler
PDMA_IRQHandler
I2S_IRQHandler
PDWU_IRQHandler
ADC_IRQHandler
DAC_IRQHandler
RTC_IRQHandler
B .
ENDP
;缺省對齊方式，具體對齊字節平臺相關
ALIGN
; User Initial Stack & Heap
;宏開關，相當C語言IFDEF,定義__MICROLIB則執行,由於爲定義執行ELSE分支
IF :DEF:__MICROLIB
EXPORT __initial_sp
EXPORT __heap_base
EXPORT __heap_limit
ELSE
;外部申明，可用於其他地方初始化棧和堆，調用C之前必須初始化棧
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
轉自：https://blog.csdn.net/CSDN_weng/article/details/50963675