基于 LPC1114 的 M0 启动流程分析

基于LPC1114的M0启动流程分析

作者：解琛
时间：2020 年 8 月 1 日

一、.s 启动进程

首先关注 LPC1114 的启动文件，为了低成本的需要，使用芯片内部的晶振，所以这里需要对启动文件进行修改。

先看一下 startup_LPC11xx.s 文件，其代码如下。

;/**************************************************************************//**
; * @file     startup_LPC11xx.s
; * @brief    CMSIS Cortex-M0 Core Device Startup File
; *           for the NXP LPC11xx/LPC11Cxx Device Series
; * @version  V1.10
; * @date     24. November 2010
; *------- <<< Use Configuration Wizard in Context Menu >>> ------------------
; *
; * @note
; * Copyright (C) 2009-2010 ARM Limited. All rights reserved.
; *
; * @par
; * ARM Limited (ARM) is supplying this software for use with Cortex-M 
; * processor based microcontrollers.  This file can be freely distributed 
; * within development tools that are supporting such ARM based processors. 
; *
; * @par
; * 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     0x00000400

                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     0x00000000

                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     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     WAKEUP_IRQHandler         ; 16+ 0: Wakeup PIO0.0
                DCD     WAKEUP_IRQHandler         ; 16+ 1: Wakeup PIO0.1
                DCD     WAKEUP_IRQHandler         ; 16+ 2: Wakeup PIO0.2
                DCD     WAKEUP_IRQHandler         ; 16+ 3: Wakeup PIO0.3
                DCD     WAKEUP_IRQHandler         ; 16+ 4: Wakeup PIO0.4
                DCD     WAKEUP_IRQHandler         ; 16+ 5: Wakeup PIO0.5
                DCD     WAKEUP_IRQHandler         ; 16+ 6: Wakeup PIO0.6
                DCD     WAKEUP_IRQHandler         ; 16+ 7: Wakeup PIO0.7
                DCD     WAKEUP_IRQHandler         ; 16+ 8: Wakeup PIO0.8
                DCD     WAKEUP_IRQHandler         ; 16+ 9: Wakeup PIO0.9
                DCD     WAKEUP_IRQHandler         ; 16+10: Wakeup PIO0.10
                DCD     WAKEUP_IRQHandler         ; 16+11: Wakeup PIO0.11
                DCD     WAKEUP_IRQHandler         ; 16+12: Wakeup PIO1.0
                DCD     CAN_IRQHandler            ; 16+13: CAN
                DCD     SSP1_IRQHandler           ; 16+14: SSP1
                DCD     I2C_IRQHandler            ; 16+15: I2C
                DCD     TIMER16_0_IRQHandler      ; 16+16: 16-bit Counter-Timer 0
                DCD     TIMER16_1_IRQHandler      ; 16+17: 16-bit Counter-Timer 1
                DCD     TIMER32_0_IRQHandler      ; 16+18: 32-bit Counter-Timer 0
                DCD     TIMER32_1_IRQHandler      ; 16+19: 32-bit Counter-Timer 1
                DCD     SSP0_IRQHandler           ; 16+20: SSP0
                DCD     UART_IRQHandler           ; 16+21: UART
                DCD     USB_IRQHandler            ; 16+22: USB IRQ
                DCD     USB_FIQHandler            ; 16+24: USB FIQ
                DCD     ADC_IRQHandler            ; 16+24: A/D Converter
                DCD     WDT_IRQHandler            ; 16+25: Watchdog Timer
                DCD     BOD_IRQHandler            ;