(转)Cortex-M3 (NXP LPC1788)之启动代码分析

在Keil uVision4中新建一个基于NXP1788的工程后，会提示添加启动汇编代码startup_LPC177x_8x.S。该文件进行从汇编到C语言运行环境的初始化工作。

 

[cpp]
  1. ;/*****************************************************************************
  2. ; * @file:    startup_LPC177x_8x.s
  3. ; * @purpose: CMSIS Cortex-M3 Core Device Startup File
  4. ; *           for the NXP LPC177x_8x Device Series
  5. ; * @version: V1.20
  6. ; * @date:    07. October 2010
  7. ; *------- <<< Use Configuration Wizard in Context Menu >>> ------------------
  8. ; *
  9. ; * Copyright (C) 2010 ARM Limited. All rights reserved.
  10. ; * ARM Limited (ARM) is supplying this software for use with Cortex-M3
  11. ; * processor based microcontrollers.  This file can be freely distributed
  12. ; * within development tools that are supporting such ARM based processors.
  13. ; *
  14. ; * THIS SOFTWARE IS PROVIDED "AS IS".  NO WARRANTIES, WHETHER EXPRESS, IMPLIED
  15. ; * OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF
  16. ; * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE.
  17. ; * ARM SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR
  18. ; * CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
  19. ; *
  20. ; *****************************************************************************/ 
  21.  
  22.  
  23. ; <h> Stack Configuration 
  24. ;   <o> Stack Size (in Bytes) <0x0-0xFFFFFFFF:8> 
  25. ; </h> 
  26.  
  27. Stack_Size      EQU     0x00000200 
  28.  
  29.                 AREA    STACK, NOINIT, READWRITE, ALIGN=3 
  30. Stack_Mem       SPACE   Stack_Size 
  31. __initial_sp 
  32.  
  33.  
  34. ; <h> Heap Configuration 
  35. ;   <o>  Heap Size (in Bytes) <0x0-0xFFFFFFFF:8> 
  36. ; </h> 
  37.  
  38. Heap_Size       EQU     0x00000400 
  39.  
  40.                 AREA    HEAP, NOINIT, READWRITE, ALIGN=3 
  41. __heap_base 
  42. Heap_Mem        SPACE   Heap_Size 
  43. __heap_limit 
  44.  
  45.  
  46.                 PRESERVE8 
  47.                 THUMB 
  48.  
  49.  
  50. ; Vector Table Mapped to Address 0 at Reset 
  51.  
  52.                 AREA    RESET, DATA, READONLY 
  53.                 EXPORT  __Vectors 
  54.  
  55. __Vectors       DCD     __initial_sp              ; Top of Stack 
  56.                 DCD     Reset_Handler             ; Reset Handler 
  57.                 DCD     NMI_Handler               ; NMI Handler 
  58.                 DCD     HardFault_Handler         ; Hard Fault Handler 
  59.                 DCD     MemManage_Handler         ; MPU Fault Handler 
  60.                 DCD     BusFault_Handler          ; Bus Fault Handler 
  61.                 DCD     UsageFault_Handler        ; Usage Fault Handler 
  62.                 DCD     0                         ; Reserved 
  63.                 DCD     0                         ; Reserved 
  64.                 DCD     0                         ; Reserved 
  65.                 DCD     0                         ; Reserved 
  66.                 DCD     SVC_Handler               ; SVCall Handler 
  67.                 DCD     DebugMon_Handler          ; Debug Monitor Handler 
  68.                 DCD     0                         ; Reserved 
  69.                 DCD     PendSV_Handler            ; PendSV Handler 
  70.                 DCD     SysTick_Handler           ; SysTick Handler 
  71.  
  72.                 ; External Interrupts 
  73.                 DCD     WDT_IRQHandler            ; 16: Watchdog Timer 
  74.                 DCD     TIMER0_IRQHandler         ; 17: Timer0 
  75.                 DCD     TIMER1_IRQHandler         ; 18: Timer1 
  76.                 DCD     TIMER2_IRQHandler         ; 19: Timer2 
  77.                 DCD     TIMER3_IRQHandler         ; 20: Timer3 
  78.                 DCD     UART0_IRQHandler          ; 21: UART0 
  79.                 DCD     UART1_IRQHandler          ; 22: UART1 
  80.                 DCD     UART2_IRQHandler          ; 23: UART2 
  81.                 DCD     UART3_IRQHandler          ; 24: UART3 
  82.                 DCD     PWM1_IRQHandler           ; 25: PWM1 
  83.                 DCD     I2C0_IRQHandler           ; 26: I2C0 
  84.                 DCD     I2C1_IRQHandler           ; 27: I2C1 
  85.                 DCD     I2C2_IRQHandler           ; 28: I2C2 
  86.                 DCD     SPIFI_IRQHandler          ; 29: SPIFI 
  87.                 DCD     SSP0_IRQHandler           ; 30: SSP0 
  88.                 DCD     SSP1_IRQHandler           ; 31: SSP1 
  89.                 DCD     PLL0_IRQHandler           ; 32: PLL0 Lock (Main PLL) 
  90.                 DCD     RTC_IRQHandler            ; 33: Real Time Clock 
  91.                 DCD     EINT0_IRQHandler          ; 34: External Interrupt 0 
  92.                 DCD     EINT1_IRQHandler          ; 35: External Interrupt 1 
  93.                 DCD     EINT2_IRQHandler          ; 36: External Interrupt 2 
  94.                 DCD     EINT3_IRQHandler          ; 37: External Interrupt 3 
  95.                 DCD     ADC_IRQHandler            ; 38: A/D Converter 
  96.                 DCD     BOD_IRQHandler            ; 39: Brown-Out Detect 
  97.                 DCD     USB_IRQHandler            ; 40: USB 
  98.                 DCD     CAN_IRQHandler            ; 41: CAN 
  99.                 DCD     DMA_IRQHandler            ; 42: General Purpose DMA 
  100.                 DCD     I2S_IRQHandler            ; 43: I2S 
  101.                 DCD     ENET_IRQHandler           ; 44: Ethernet 
  102.                 DCD     MCI_IRQHandler            ; 45: SD/MMC card I/F 
  103.                 DCD     MCPWM_IRQHandler          ; 46: Motor Control PWM 
  104.                 DCD     QEI_IRQHandler            ; 47: Quadrature Encoder Interface 
  105.                 DCD     PLL1_IRQHandler           ; 48: PLL1 Lock (USB PLL) 
  106.                 DCD     USBActivity_IRQHandler    ; 49: USB Activity interrupt to wakeup 
  107.                 DCD     CANActivity_IRQHandler    ; 50: CAN Activity interrupt to wakeup 
  108.                 DCD     UART4_IRQHandler          ; 51: UART4 
  109.                 DCD     SSP2_IRQHandler           ; 52: SSP2 
  110.                 DCD     LCD_IRQHandler            ; 53: LCD 
  111.                 DCD     GPIO_IRQHandler           ; 54: GPIO 
  112.                 DCD     PWM0_IRQHandler           ; 55: PWM0 
  113.                 DCD     EEPROM_IRQHandler         ; 56: EEPROM 
  114.  
  115.  
  116.                 IF      :LNOT::DEF:NO_CRP 
  117.                 AREA    |.ARM.__at_0x02FC|, CODE, READONLY 
  118. CRP_Key         DCD     0xFFFFFFFF 
  119.                 ENDIF 
  120.  
  121.  
  122.                 AREA    |.text|, CODE, READONLY 
  123.  
  124.  
  125. ; Reset Handler 
  126.  
  127. Reset_Handler   PROC 
  128.                 EXPORT  Reset_Handler             [WEAK] 
  129.                 IMPORT  SystemInit 
  130.                 IMPORT  __main 
  131.                 LDR     R0, =SystemInit 
  132.                 BLX     R0 
  133.                 LDR     R0, =__main 
  134.                 BX      R0 
  135.                 ENDP 
  136.  
  137.  
  138. ; Dummy Exception Handlers (infinite loops which can be modified) 
  139.  
  140. NMI_Handler     PROC 
  141.                 EXPORT  NMI_Handler               [WEAK] 
  142.                 B       . 
  143.                 ENDP 
  144. HardFault_Handler\ 
  145.                 PROC 
  146.                 EXPORT  HardFault_Handler         [WEAK] 
  147.                 B       . 
  148.                 ENDP 
  149. MemManage_Handler\ 
  150.                 PROC 
  151.                 EXPORT  MemManage_Handler         [WEAK] 
  152.                 B       . 
  153.                 ENDP 
  154. BusFault_Handler\ 
  155.                 PROC 
  156.                 EXPORT  BusFault_Handler          [WEAK] 
  157.                 B       . 
  158.                 ENDP 
  159. UsageFault_Handler\ 
  160.                 PROC 
  161.                 EXPORT  UsageFault_Handler        [WEAK] 
  162.                 B       . 
  163.                 ENDP 
  164. SVC_Handler     PROC 
  165.                 EXPORT  SVC_Handler               [WEAK] 
  166.                 B       . 
  167.                 ENDP 
  168. DebugMon_Handler\ 
  169.                 PROC 
  170.                 EXPORT  DebugMon_Handler          [WEAK] 
  171.                 B       . 
  172.                 ENDP 
  173. PendSV_Handler  PROC 
  174.                 EXPORT  PendSV_Handler            [WEAK] 
  175.                 B       . 
  176.                 ENDP 
  177. SysTick_Handler PROC 
  178.                 EXPORT  SysTick_Handler           [WEAK] 
  179.                 B       . 
  180.                 ENDP 
  181.  
  182. Default_Handler PROC 
  183.  
  184.                 EXPORT  WDT_IRQHandler            [WEAK] 
  185.                 EXPORT  TIMER0_IRQHandler         [WEAK] 
  186.                 EXPORT  TIMER1_IRQHandler         [WEAK] 
  187.                 EXPORT  TIMER2_IRQHandler         [WEAK] 
  188.                 EXPORT  TIMER3_IRQHandler         [WEAK] 
  189.                 EXPORT  UART0_IRQHandler          [WEAK] 
  190.                 EXPORT  UART1_IRQHandler          [WEAK] 
  191.                 EXPORT  UART2_IRQHandler          [WEAK] 
  192.                 EXPORT  UART3_IRQHandler          [WEAK] 
  193.                 EXPORT  PWM1_IRQHandler           [WEAK] 
  194.                 EXPORT  I2C0_IRQHandler           [WEAK] 
  195.                 EXPORT  I2C1_IRQHandler           [WEAK] 
  196.                 EXPORT  I2C2_IRQHandler           [WEAK] 
  197.                 EXPORT  SPIFI_IRQHandler          [WEAK] 
  198.                 EXPORT  SSP0_IRQHandler           [WEAK] 
  199.                 EXPORT  SSP1_IRQHandler           [WEAK] 
  200.                 EXPORT  PLL0_IRQHandler           [WEAK] 
  201.                 EXPORT  RTC_IRQHandler            [WEAK] 
  202.                 EXPORT  EINT0_IRQHandler          [WEAK] 
  203.                 EXPORT  EINT1_IRQHandler          [WEAK] 
  204.                 EXPORT  EINT2_IRQHandler          [WEAK] 
  205.                 EXPORT  EINT3_IRQHandler          [WEAK] 
  206.                 EXPORT  ADC_IRQHandler            [WEAK] 
  207.                 EXPORT  BOD_IRQHandler            [WEAK] 
  208.                 EXPORT  USB_IRQHandler            [WEAK] 
  209.                 EXPORT  CAN_IRQHandler            [WEAK] 
  210.                 EXPORT  DMA_IRQHandler            [WEAK] 
  211.                 EXPORT  I2S_IRQHandler            [WEAK] 
  212.                 EXPORT  ENET_IRQHandler           [WEAK] 
  213.                 EXPORT  MCI_IRQHandler            [WEAK] 
  214.                 EXPORT  MCPWM_IRQHandler          [WEAK] 
  215.                 EXPORT  QEI_IRQHandler            [WEAK] 
  216.                 EXPORT  PLL1_IRQHandler           [WEAK] 
  217.                 EXPORT  USBActivity_IRQHandler    [WEAK] 
  218.                 EXPORT  CANActivity_IRQHandler    [WEAK] 
  219.                 EXPORT  UART4_IRQHandler          [WEAK] 
  220.                 EXPORT  SSP2_IRQHandler           [WEAK] 
  221.                 EXPORT  LCD_IRQHandler            [WEAK] 
  222.                 EXPORT  GPIO_IRQHandler           [WEAK] 
  223.                 EXPORT  PWM0_IRQHandler           [WEAK] 
  224.                 EXPORT  EEPROM_IRQHandler         [WEAK] 
  225.  
  226. WDT_IRQHandler 
  227. TIMER0_IRQHandler 
  228. TIMER1_IRQHandler 
  229. TIMER2_IRQHandler 
  230. TIMER3_IRQHandler 
  231. UART0_IRQHandler 
  232. UART1_IRQHandler 
  233. UART2_IRQHandler 
  234. UART3_IRQHandler 
  235. PWM1_IRQHandler 
  236. I2C0_IRQHandler 
  237. I2C1_IRQHandler 
  238. I2C2_IRQHandler 
  239. SPIFI_IRQHandler             
  240. SSP0_IRQHandler 
  241. SSP1_IRQHandler 
  242. PLL0_IRQHandler 
  243. RTC_IRQHandler 
  244. EINT0_IRQHandler 
  245. EINT1_IRQHandler 
  246. EINT2_IRQHandler 
  247. EINT3_IRQHandler 
  248. ADC_IRQHandler 
  249. BOD_IRQHandler 
  250. USB_IRQHandler 
  251. CAN_IRQHandler 
  252. DMA_IRQHandler 
  253. I2S_IRQHandler 
  254. ENET_IRQHandler 
  255. MCI_IRQHandler           
  256. MCPWM_IRQHandler 
  257. QEI_IRQHandler 
  258. PLL1_IRQHandler 
  259. USBActivity_IRQHandler 
  260. CANActivity_IRQHandler 
  261. UART4_IRQHandler 
  262. SSP2_IRQHandler 
  263. LCD_IRQHandler 
  264. GPIO_IRQHandler 
  265. PWM0_IRQHandler 
  266. EEPROM_IRQHandler 
  267.  
  268.                 B       . 
  269.  
  270.                 ENDP 
  271.  
  272.  
  273.                 ALIGN 
  274.  
  275.  
  276. ; User Initial Stack & Heap 
  277.  
  278.                 IF      :DEF:__MICROLIB 
  279.  
  280.                 EXPORT  __initial_sp 
  281.                 EXPORT  __heap_base 
  282.                 EXPORT  __heap_limit 
  283.  
  284.                 ELSE 
  285.  
  286.                 IMPORT  __use_two_region_memory 
  287.                 EXPORT  __user_initial_stackheap 
  288. __user_initial_stackheap 
  289.  
  290.                 LDR     R0, =  Heap_Mem 
  291.                 LDR     R1, =(Stack_Mem + Stack_Size) 
  292.                 LDR     R2, = (Heap_Mem +  Heap_Size) 
  293.                 LDR     R3, = Stack_Mem 
  294.                 BX      LR 
  295.  
  296.                 ALIGN 
  297.  
  298.                 ENDIF 
  299.  
  300.  
  301.                 END  
;/*****************************************************************************
; * @file:    startup_LPC177x_8x.s
; * @purpose: CMSIS Cortex-M3 Core Device Startup File
; *           for the NXP LPC177x_8x Device Series 
; * @version: V1.20
; * @date:    07. October 2010
; *------- <<< Use Configuration Wizard in Context Menu >>> ------------------
; *
; * Copyright (C) 2010 ARM Limited. All rights reserved.
; * ARM Limited (ARM) is supplying this software for use with Cortex-M3
; * processor based microcontrollers.  This file can be freely distributed
; * within development tools that are supporting such ARM based processors.
; *
; * THIS SOFTWARE IS PROVIDED "AS IS".  NO WARRANTIES, WHETHER EXPRESS, IMPLIED
; * OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF
; * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE.
; * ARM SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR
; * CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
; *
; *****************************************************************************/


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

Stack_Size      EQU     0x00000200

                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     0x00000400

                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

__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     WDT_IRQHandler            ; 16: Watchdog Timer
                DCD     TIMER0_IRQHandler         ; 17: Timer0
                DCD     TIMER1_IRQHandler         ; 18: Timer1
                DCD     TIMER2_IRQHandler         ; 19: Timer2
                DCD     TIMER3_IRQHandler         ; 20: Timer3
                DCD     UART0_IRQHandler          ; 21: UART0
                DCD     UART1_IRQHandler          ; 22: UART1
                DCD     UART2_IRQHandler          ; 23: UART2
                DCD     UART3_IRQHandler          ; 24: UART3
                DCD     PWM1_IRQHandler           ; 25: PWM1
                DCD     I2C0_IRQHandler           ; 26: I2C0
                DCD     I2C1_IRQHandler           ; 27: I2C1
                DCD     I2C2_IRQHandler           ; 28: I2C2
                DCD     SPIFI_IRQHandler          ; 29: SPIFI
                DCD     SSP0_IRQHandler           ; 30: SSP0
                DCD     SSP1_IRQHandler           ; 31: SSP1
                DCD     PLL0_IRQHandler           ; 32: PLL0 Lock (Main PLL)
                DCD     RTC_IRQHandler            ; 33: Real Time Clock
                DCD     EINT0_IRQHandler          ; 34: External Interrupt 0
                DCD     EINT1_IRQHandler          ; 35: External Interrupt 1
                DCD     EINT2_IRQHandler          ; 36: External Interrupt 2
                DCD     EINT3_IRQHandler          ; 37: External Interrupt 3
                DCD     ADC_IRQHandler            ; 38: A/D Converter
                DCD     BOD_IRQHandler            ; 39: Brown-Out Detect
                DCD     USB_IRQHandler            ; 40: USB
                DCD     CAN_IRQHandler            ; 41: CAN
                DCD     DMA_IRQHandler            ; 42: General Purpose DMA
                DCD     I2S_IRQHandler            ; 43: I2S
                DCD     ENET_IRQHandler           ; 44: Ethernet
                DCD     MCI_IRQHandler            ; 45: SD/MMC card I/F
                DCD     MCPWM_IRQHandler          ; 46: Motor Control PWM
                DCD     QEI_IRQHandler            ; 47: Quadrature Encoder Interface
                DCD     PLL1_IRQHandler           ; 48: PLL1 Lock (USB PLL)
				DCD		USBActivity_IRQHandler    ; 49: USB Activity interrupt to wakeup
				DCD		CANActivity_IRQHandler    ; 50: CAN Activity interrupt to wakeup
				DCD		UART4_IRQHandler          ; 51: UART4
				DCD		SSP2_IRQHandler           ; 52: SSP2
				DCD		LCD_IRQHandler            ; 53: LCD
				DCD		GPIO_IRQHandler           ; 54: GPIO
				DCD		PWM0_IRQHandler           ; 55: PWM0
				DCD		EEPROM_IRQHandler         ; 56: EEPROM


                IF      :LNOT::DEF:NO_CRP
                AREA    |.ARM.__at_0x02FC|, CODE, READONLY
CRP_Key         DCD     0xFFFFFFFF
                ENDIF


                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  WDT_IRQHandler            [WEAK]
                EXPORT  TIMER0_IRQHandler         [WEAK]
                EXPORT  TIMER1_IRQHandler         [WEAK]
                EXPORT  TIMER2_IRQHandler         [WEAK]
                EXPORT  TIMER3_IRQHandler         [WEAK]
                EXPORT  UART0_IRQHandler          [WEAK]
                EXPORT  UART1_IRQHandler          [WEAK]
                EXPORT  UART2_IRQHandler          [WEAK]
                EXPORT  UART3_IRQHandler          [WEAK]
                EXPORT  PWM1_IRQHandler           [WEAK]
                EXPORT  I2C0_IRQHandler           [WEAK]
                EXPORT  I2C1_IRQHandler           [WEAK]
                EXPORT  I2C2_IRQHandler           [WEAK]
                EXPORT  SPIFI_IRQHandler          [WEAK]
                EXPORT  SSP0_IRQHandler           [WEAK]
                EXPORT  SSP1_IRQHandler           [WEAK]
                EXPORT  PLL0_IRQHandler           [WEAK]
                EXPORT  RTC_IRQHandler            [WEAK]
                EXPORT  EINT0_IRQHandler          [WEAK]
                EXPORT  EINT1_IRQHandler          [WEAK]
                EXPORT  EINT2_IRQHandler          [WEAK]
                EXPORT  EINT3_IRQHandler          [WEAK]
                EXPORT  ADC_IRQHandler            [WEAK]
                EXPORT  BOD_IRQHandler            [WEAK]
                EXPORT  USB_IRQHandler            [WEAK]
                EXPORT  CAN_IRQHandler            [WEAK]
                EXPORT  DMA_IRQHandler            [WEAK]
                EXPORT  I2S_IRQHandler            [WEAK]
                EXPORT  ENET_IRQHandler           [WEAK]
                EXPORT  MCI_IRQHandler            [WEAK]
                EXPORT  MCPWM_IRQHandler          [WEAK]
                EXPORT  QEI_IRQHandler            [WEAK]
                EXPORT  PLL1_IRQHandler           [WEAK]
				EXPORT  USBActivity_IRQHandler    [WEAK]
				EXPORT  CANActivity_IRQHandler    [WEAK]
				EXPORT  UART4_IRQHandler          [WEAK]
				EXPORT  SSP2_IRQHandler           [WEAK]
				EXPORT  LCD_IRQHandler            [WEAK]
				EXPORT  GPIO_IRQHandler           [WEAK]
				EXPORT  PWM0_IRQHandler           [WEAK]
				EXPORT  EEPROM_IRQHandler         [WEAK]

WDT_IRQHandler
TIMER0_IRQHandler
TIMER1_IRQHandler
TIMER2_IRQHandler
TIMER3_IRQHandler
UART0_IRQHandler
UART1_IRQHandler
UART2_IRQHandler
UART3_IRQHandler
PWM1_IRQHandler
I2C0_IRQHandler
I2C1_IRQHandler
I2C2_IRQHandler
SPIFI_IRQHandler            
SSP0_IRQHandler
SSP1_IRQHandler
PLL0_IRQHandler
RTC_IRQHandler
EINT0_IRQHandler
EINT1_IRQHandler
EINT2_IRQHandler
EINT3_IRQHandler
ADC_IRQHandler
BOD_IRQHandler
USB_IRQHandler
CAN_IRQHandler
DMA_IRQHandler
I2S_IRQHandler
ENET_IRQHandler
MCI_IRQHandler          
MCPWM_IRQHandler
QEI_IRQHandler
PLL1_IRQHandler
USBActivity_IRQHandler
CANActivity_IRQHandler
UART4_IRQHandler
SSP2_IRQHandler
LCD_IRQHandler
GPIO_IRQHandler
PWM0_IRQHandler
EEPROM_IRQHandler

                B       .

                ENDP


                ALIGN


; User Initial Stack & Heap

                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

程序完成如下内容的工作：

 

        开辟一块大小为Stack_Size的栈空间；

        标号__initial_sp指向栈顶位置；

        定义堆空间大小为Heap_Size；

        建立中断向量表Vectors，cortex-M3规定起始地址必须存放栈顶地址即__initial_sp，紧接着存放复位入口地址，这样内核复位后就会自动从起始地址的下32位取出复位地址执行复位中断服务函数。

        Reset_Handler复位中断函数中先EXPORT声明Reset_Handler的全局性，然后分别执行外部的函数SystemInit和__main。

 

 

下面对汇编程序中的几个关键字做说明：

        AREA伪指令：用于定义代码段和数据段，后跟属性标号。其中“READWRITE”表示可读写，“READONLY”只读属性。根据LPC1788的数据手册描述的存储介质，可知可读写段保持在SRAM区，起始地址为0x1000 0000，代码中的堆栈保存在SRAM空间。只读段保存在Flash区，起始地址为0x0000 0000，代码中的中断向量表保存在Flash空间。 因此可以总结出，在0x0000 0000 存放的是栈顶的地址__initial_sp（即0x1000 0200），在0x0000 0004 存放的是Reset_Handler的地址。

LPCaddresS

图1：LPC1788 地址映射

memoryLPC

图2： debug中 0地址的值0x1000 0200 即栈顶地址， 0x0000 0004 地址值为0x0000 00F9（看反汇编可知该值 即Reset_Handler的入口如下图）。

0XF9

 

        DCD指令：开辟内存空间，中断向量表建立中使用相当于C语言中的函数指针，每个成员都是函数指针，指向各个中断服务函数。

 

 

        自此分析了LPC1788的启动，主要包括堆栈初始化，和中断向量表的初始化。LPC1788有内部Flash，所以上点从内部Flash启动，内部Flash的起始地址为0x0000 0000，存放栈顶的地址0x1000 0200。 0x0000 0004存放复位中断的入口地址。LPC1788复位后，从0x0000 0004取出复位入口地址，执行中断复位函数，从而跳转到SystemInit和main C语言函数执行。

 

posted on 2012-09-26 07:34  tdyizhen1314  阅读(3757)  评论(0)  编辑  收藏  举报

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