" ARM裸机篇---启动代码分析 "

ARM裸机篇---启动代码分析

　　先搞清楚启动代码和Bootloader的区别，启动代码是指CPU复位后到进入C语言的main函数之前需要执行的那段汇编代码。

下面的代码先暂且这样吧，没啥注释的，时间关系，我还是先搞些应用再说^_^

;=========================================; NAME: 2410INIT.S; DESC: C start up codes;       Configure memory, ISR ,stacks;Initialize C-variables; HISTORY:; 2002.02.25:kwtark: ver 0.0; 2002.03.20:purnnamu: Add some functions for testing STOP,POWER_OFF mode; 2002.04.10:SJS:sub interrupt disable 0x3ff -> 0x7ff ;=========================================GET option.sGET memcfg.sGET 2410addr.s BIT_SELFREFRESH EQU(1<<22);Pre-defined constantsUSERMODE    EQU 0x10FIQMODE     EQU 0x11IRQMODE     EQU 0x12SVCMODE     EQU 0x13ABORTMODE   EQU 0x17UNDEFMODE   EQU 0x1bMODEMASK    EQU 0x1fNOINT       EQU 0xc0;The location of stacksUserStack   EQU (_STACK_BASEADDRESS-0x3800) ;0x33ff4800 ~ SVCStack    EQU (_STACK_BASEADDRESS-0x2800) ;0x33ff5800 ~UndefStack  EQU (_STACK_BASEADDRESS-0x2400) ;0x33ff5c00 ~AbortStack  EQU (_STACK_BASEADDRESS-0x2000) ;0x33ff6000 ~IRQStack    EQU (_STACK_BASEADDRESS-0x1000) ;0x33ff7000 ~FIQStack    EQU (_STACK_BASEADDRESS-0x0)    ;0x33ff8000 ~ ;Check if tasm.exe(armasm -16 ...@ADS 1.0) is used.GBLL    THUMBCODE[ {CONFIG} = 16 THUMBCODE SETL  {TRUE}    CODE32    |   THUMBCODE SETL  {FALSE}    ]    MACROMOV_PC_LR    [ THUMBCODE            bx lr    |            movpc,lr    ]MEND    MACROMOVEQ_PC_LR    [ THUMBCODE        bxeq lr    |            moveq pc,lr    ] MEND    MACRO$HandlerLabel HANDLER $HandleLabel$HandlerLabelsubsp,sp,#4        ;decrement sp(to store jump address)stmfdsp!,{r0}        ;PUSH the work register to stack(lr does"t push because it return to original address)ldr     r0,=$HandleLabel;load the address of HandleXXX to r0ldr     r0,[r0]         ;load the contents(service routine start address) of HandleXXXstr     r0,[sp,#4]      ;store the contents(ISR) of HandleXXX to stackldmfd   sp!,{r0,pc}     ;POP the work register and pc(jump to ISR)MENDIMPORT  |Image$$RO$$Limit|  ; End of ROM code (=start of ROM data)IMPORT  |Image$$RW$$Base|   ; Base of RAM to initialiseIMPORT  |Image$$ZI$$Base|   ; Base and limit of areaIMPORT  |Image$$ZI$$Limit|  ; to zero initialiseIMPORT  Main    ; The main entry of mon program AREA    Init,CODE,READONLYENTRY  ;1)The code, which converts to Big-endian, should be in little endian code.;2)The following little endian code will be compiled in Big-Endian mode. ;  The code byte order should be changed as the memory bus width.;3)The pseudo instruction,DCD can"t be used here because the linker generates error.ASSERT:DEF:ENDIAN_CHANGE[ ENDIAN_CHANGE    ASSERT  :DEF:ENTRY_BUS_WIDTH    [ ENTRY_BUS_WIDTH=32bChangeBigEndian    ;DCD 0xea000007     ]         [ ENTRY_BUS_WIDTH=16andeqr14,r7,r0,lsl #20   ;DCD 0x0007ea00    ]        [ ENTRY_BUS_WIDTH=8streqr0,[r0,-r10,ror #1] ;DCD 0x070000ea            ]|    bResetHandler      ]bHandlerUndef;handler for Undefined modebHandlerSWI;handler for SWI interruptbHandlerPabort;handler for PAbortbHandlerDabort;handler for DAbortb.;reservedbHandlerIRQ;handler for IRQ interrupt bHandlerFIQ;handler for FIQ interrupt;@0x20bEnterPWDNChangeBigEndian;@0x24[ ENTRY_BUS_WIDTH=32    DCD0xee110f10;0xee110f10 => mrc p15,0,r0,c1,c0,0    DCD0xe3800080;0xe3800080 => orr r0,r0,#0x80;  //Big-endian    DCD0xee010f10;0xee010f10 => mcr p15,0,r0,c1,c0,0][ ENTRY_BUS_WIDTH=16    DCD 0x0f10ee11    DCD 0x0080e380    DCD 0x0f10ee01][ ENTRY_BUS_WIDTH=8    DCD 0x100f11ee    DCD 0x800080e3    DCD 0x100f01ee    ]DCD 0xffffffff  ;swinv 0xffffff is similar with NOP and run well in both endian mode. DCD 0xffffffffDCD 0xffffffffDCD 0xffffffffDCD 0xffffffffb ResetHandler;Function for entering power down mode; 1. SDRAM should be in self-refresh mode.; 2. All interrupt should be maksked for SDRAM/DRAM self-refresh.; 3. LCD controller should be disabled for SDRAM/DRAM self-refresh.; 4. The I-cache may have to be turned on. ; 5. The location of the following code may have not to be changed.;void EnterPWDN(int CLKCON); EnterPWDNmov r2,r0;r2=rCLKCONtst r0,#0x8;POWER_OFF mode?bne ENTER_POWER_OFFENTER_STOPldr r0,=REFRESHldr r3,[r0];r3=rREFRESHmov r1, r3orr r1, r1, #BIT_SELFREFRESHstr r1, [r0];Enable SDRAM self-refreshmov r1,#16   ;wait until self-refresh is issued. may not be needed.0subs r1,r1,#1bne %B0ldr r0,=CLKCON;enter STOP mode.str r2,[r0]    mov r1,#320subs r1,r1,#1;1) wait until the STOP mode is in effect.bne %B0;2) Or wait here until the CPU&Peripherals will be turned-off;   Entering POWER_OFF mode, only the reset by wake-up is available.ldr r0,=REFRESH ;exit from SDRAM self refresh mode.str r3,[r0]MOV_PC_LRENTER_POWER_OFF;NOTE.;1) rGSTATUS3 should have the return address after wake-up from POWER_OFF mode.ldr r0,=REFRESHldr r1,[r0];r1=rREFRESHorr r1, r1, #BIT_SELFREFRESHstr r1, [r0];Enable SDRAM self-refreshmov r1,#16   ;Wait until self-refresh is issued,which may not be needed.0subs r1,r1,#1bne %B0ldr r1,=MISCCRldrr0,[r1]orrr0,r0,#(7<<17)  ;Make sure that SCLK0:SCLK->0, SCLK1:SCLK->0, SCKE=L during boot-up strr0,[r1]ldr r0,=CLKCONstr r2,[r0]    b .;CPU will die here.WAKEUP_POWER_OFF;Release SCLKn after wake-up from the POWER_OFF mode.ldr r1,=MISCCRldrr0,[r1]bicr0,r0,#(7<<17)  ;SCLK0:0->SCLK, SCLK1:0->SCLK, SCKE:L->Hstrr0,[r1];Set memory control registers    ldrr0,=SMRDATAldrr1,=BWSCON;BWSCON Addressaddr2, r0, #52;End address of SMRDATA0       ldrr3, [r0], #4    strr3, [r1], #4    cmpr2, r0bne%B0mov r1,#2560subs r1,r1,#1;1) wait until the SelfRefresh is released.bne %B0 ldr r1,=GSTATUS3 ;GSTATUS3 has the start address just after POWER_OFF wake-upldr r0,[r1]mov pc,r0LTORG   HandlerFIQ      HANDLER HandleFIQHandlerIRQ      HANDLER HandleIRQHandlerUndef    HANDLER HandleUndefHandlerSWI      HANDLER HandleSWIHandlerDabort   HANDLER HandleDabortHandlerPabort   HANDLER HandlePabortIsrIRQ  subsp,sp,#4       ;reserved for PCstmfdsp!,{r8-r9}   ldrr9,=INTOFFSETldrr9,[r9]ldrr8,=HandleEINT0addr8,r8,r9,lsl #2ldrr8,[r8]strr8,[sp,#8]ldmfdsp!,{r8-r9,pc};=======; ENTRY  ;=======ResetHandlerldrr0,=WTCON       ;watch dog disable ldrr1,=0x0         strr1,[r0]ldrr0,=INTMSKldrr1,=0xffffffff  ;all interrupt disablestrr1,[r0]ldrr0,=INTSUBMSKldrr1,=0x7ff;all sub interrupt disable, 2002/04/10strr1,[r0][ {FALSE}        ; rGPFDAT = (rGPFDAT & ~(0xf<<4)) | ((~data & 0xf)<<4);            ; Led_Displayldrr0,=GPFCONldrr1,=0x5500strr1,[r0]ldrr0,=GPFDATldrr1,=0x10strr1,[r0]];To reduce PLL lock time, adjust the LOCKTIME register. ldrr0,=LOCKTIMEldrr1,=0xffffffstrr1,[r0]            [ PLL_ON_START;Configure MPLLldrr0,=MPLLCON          ldrr1,=((M_MDIV<<12)+(M_PDIV<<4)+M_SDIV)  ;Fin=12MHz,Fout=50MHzstrr1,[r0]];Check if the boot is caused by the wake-up from POWER_OFF mode.ldrr1,=GSTATUS2ldrr0,[r1]tstr0,#0x2        ;In case of the wake-up from POWER_OFF mode, go to POWER_OFF_WAKEUP handler. bneWAKEUP_POWER_OFFEXPORT StartPointAfterPowerOffWakeUpStartPointAfterPowerOffWakeUp;Set memory control registers    ldrr0,=SMRDATAldrr1,=BWSCON;BWSCON Addressaddr2, r0, #52;End address of SMRDATA0       ldrr3, [r0], #4    strr3, [r1], #4    cmpr2, r0bne%B0    ;Initialize stacksblInitStacks   ; Setup IRQ handlerldrr0,=HandleIRQ       ;This routine is neededldrr1,=IsrIRQ          ;if there isn"t "subs pc,lr,#4" at 0x18, 0x1cstrr1,[r0];Copy and paste RW data/zero initialized dataldrr0, =|Image$$RO$$Limit| ; Get pointer to ROM dataldrr1, =|Image$$RW$$Base|  ; and RAM copyldrr3, =|Image$$ZI$$Base|  ;Zero init base => top of initialised datacmpr0, r1      ; Check that they are differentbeq%F21       cmpr1, r3      ; Copy init dataldrccr2, [r0], #4    ;--> LDRCC r2, [r0] + ADD r0, r0, #4         strccr2, [r1], #4    ;--> STRCC r2, [r1] + ADD r1, r1, #4bcc%B12       ldrr1, =|Image$$ZI$$Limit| ; Top of zero init segmentmovr2, #03       cmpr3, r1      ; Zero initstrccr2, [r3], #4bcc%B3    [ :LNOT:THUMBCODE    blMain        ;Don"t use main() because ......    b.                           ]    [ THUMBCODE         ;for start-up code for Thumb mode    orrlr,pc,#1    bxlr    CODE16    blMain        ;Don"t use main() because ......    b.    CODE32    ];function initializing stacksInitStacks;Don"t use DRAM,such as stmfd,ldmfd......;SVCstack is initialized before;Under toolkit ver 2.5, "msr cpsr,r1" can be used instead of "msr cpsr_cxsf,r1"mrsr0,cpsrbicr0,r0,#MODEMASKorrr1,r0,#UNDEFMODE|NOINTmsrcpsr_cxsf,r1;UndefModeldrsp,=UndefStackorrr1,r0,#ABORTMODE|NOINTmsrcpsr_cxsf,r1;AbortModeldrsp,=AbortStackorrr1,r0,#IRQMODE|NOINTmsrcpsr_cxsf,r1;IRQModeldrsp,=IRQStack    orrr1,r0,#FIQMODE|NOINTmsrcpsr_cxsf,r1;FIQModeldrsp,=FIQStackbicr0,r0,#MODEMASK|NOINTorrr1,r0,#SVCMODEmsrcpsr_cxsf,r1;SVCModeldrsp,=SVCStack;USER mode has not be initialized.movpc,lr ;The LR register won"t be valid if the current mode is not SVC mode.LTORGSMRDATA DATA ; Memory configuration should be optimized for best performance ; The following parameter is not optimized.                     ; Memory access cycle parameter strategy; 1) The memory settings is  safe parameters even at HCLK=75Mhz.; 2) SDRAM refresh period is for HCLK=75Mhz.         DCD (0+(B1_BWSCON<<4)+(B2_BWSCON<<8)+(B3_BWSCON<<12)+(B4_BWSCON<<16)+(B5_BWSCON<<20)+(B6_BWSCON<<24)+(B7_BWSCON<<28))    DCD ((B0_Tacs<<13)+(B0_Tcos<<11)+(B0_Tacc<<8)+(B0_Tcoh<<6)+(B0_Tah<<4)+(B0_Tacp<<2)+(B0_PMC))   ;GCS0    DCD ((B1_Tacs<<13)+(B1_Tcos<<11)+(B1_Tacc<<8)+(B1_Tcoh<<6)+(B1_Tah<<4)+(B1_Tacp<<2)+(B1_PMC))   ;GCS1     DCD ((B2_Tacs<<13)+(B2_Tcos<<11)+(B2_Tacc<<8)+(B2_Tcoh<<6)+(B2_Tah<<4)+(B2_Tacp<<2)+(B2_PMC))   ;GCS2    DCD ((B3_Tacs<<13)+(B3_Tcos<<11)+(B3_Tacc<<8)+(B3_Tcoh<<6)+(B3_Tah<<4)+(B3_Tacp<<2)+(B3_PMC))   ;GCS3    DCD ((B4_Tacs<<13)+(B4_Tcos<<11)+(B4_Tacc<<8)+(B4_Tcoh<<6)+(B4_Tah<<4)+(B4_Tacp<<2)+(B4_PMC))   ;GCS4    DCD ((B5_Tacs<<13)+(B5_Tcos<<11)+(B5_Tacc<<8)+(B5_Tcoh<<6)+(B5_Tah<<4)+(B5_Tacp<<2)+(B5_PMC))   ;GCS5    DCD ((B6_MT<<15)+(B6_Trcd<<2)+(B6_SCAN))    ;GCS6    DCD ((B7_MT<<15)+(B7_Trcd<<2)+(B7_SCAN))    ;GCS7    DCD ((REFEN<<23)+(TREFMD<<22)+(Trp<<20)+(Trc<<18)+(Tchr<<16)+REFCNT)    DCD 0x32            ;SCLK power saving mode, BANKSIZE 128M/128M    DCD 0x30            ;MRSR6 CL=3clk    DCD 0x30            ;MRSR7;    DCD 0x20            ;MRSR6 CL=2clk;    DCD 0x20            ;MRSR7    ALIGN    AREA RamData, DATA, READWRITE        ^   _ISR_STARTADDRESSHandleReset #   4HandleUndef #   4HandleSWI   #   4HandlePabort    #   4HandleDabort    #   4HandleReserved  #   4HandleIRQ   #   4HandleFIQ   #   4;Don"t use the label "IntVectorTable",;The value of IntVectorTable is different with the address you think it may be.;IntVectorTableHandleEINT0   #   4HandleEINT1   #   4HandleEINT2   #   4HandleEINT3   #   4HandleEINT4_7#   4HandleEINT8_23#   4HandleRSV6#   4HandleBATFLT   #   4HandleTICK   #   4HandleWDT#   4HandleTIMER0 #   4HandleTIMER1 #   4HandleTIMER2 #   4HandleTIMER3 #   4HandleTIMER4 #   4HandleUART2  #   4HandleLCD #   4HandleDMA0#   4HandleDMA1#   4HandleDMA2#   4HandleDMA3#   4HandleMMC#   4HandleSPI0#   4HandleUART1#   4HandleRSV24#   4HandleUSBD#   4HandleUSBH#   4HandleIIC   #   4HandleUART0 #   4HandleSPI1 #   4HandleRTC #   4HandleADC #   4        END

上面这个还没啥注释的，下面请看这个有注释的吧，这个是实验室买的设备带的：

;*--------------------------------------------- 文件信息 ----------------------------------------------------                                      ;*;* 文件名称 : 2410INIT.S;* 文件功能 : 该文件为ARM9硬件平台的C语言启动代码，用于分配中断向量表，初始化ISR地址，初始化堆栈空间，;*            初始化应用程序执行环境，配置存储器系统，设定时钟周期，呼叫主应用程序。;* 补充说明 : 基于S3C2410的ARM9硬件平台的启动代码;*-------------------------------------------- 最新版本信息 -------------------------------------------------;* 修改作者 : ARM开发小组;* 修改日期 : 2005/08/23;* 版本声明 : V1.0.1;*-------------------------------------------- 历史版本信息 -------------------------------------------------;* 文件作者 : ARM开发小组;* 创建日期 : 2004/04/20;* 版本声明 : v1.0.0;*-----------------------------------------------------------------------------------------------------------;*-----------------------------------------------------------------------------------------------------------;************************************************************************************************************;*/GET option.sGET memcfg.sGET 2410addr.sBIT_SELFREFRESH EQU(1<<22);//Pre-defined constantsUSERMODE    EQU 0x10FIQMODE     EQU 0x11IRQMODE     EQU 0x12SVCMODE     EQU 0x13ABORTMODE   EQU 0x17UNDEFMODE   EQU 0x1bMODEMASK    EQU 0x1fNOINT       EQU 0xc0;//The location of stacksUserStackEQU(_STACK_BASEADDRESS-0x3800);//0x33ff4800 ~ SVCStack    EQU(_STACK_BASEADDRESS-0x2800)     ;//0x33ff5800 ~UndefStackEQU(_STACK_BASEADDRESS-0x2400) ;//0x33ff5c00 ~AbortStackEQU(_STACK_BASEADDRESS-0x2000) ;//0x33ff6000 ~IRQStack    EQU(_STACK_BASEADDRESS-0x1000)    ;//0x33ff7000 ~FIQStackEQU(_STACK_BASEADDRESS-0x0);//0x33ff8000 ~ ;//Check if tasm.exe(armasm -16 ...@ADS 1.0) is used.GBLL    THUMBCODE[ {CONFIG} = 16 THUMBCODE SETL  {TRUE}    CODE32    |   THUMBCODE SETL  {FALSE}    ]    MACROMOV_PC_LR    [ THUMBCODE            bx lr    |            movpc,lr    ]MEND    MACROMOVEQ_PC_LR    [ THUMBCODE        bxeq lr    |            moveq pc,lr    ]MEND    MACRO$HandlerLabel HANDLER $HandleLabel$HandlerLabelsubsp,sp,#4        ;//decrement sp(to store jump address)stmfdsp!,{r0}        ;//PUSH the work register to stack(lr does"t push because it return to original address)ldr     r0,=$HandleLabel;//load the address of HandleXXX to r0ldr     r0,[r0]         ;//load the contents(service routine start address) of HandleXXXstr     r0,[sp,#4]      ;//store the contents(ISR) of HandleXXX to stackldmfd   sp!,{r0,pc}     ;//POP the work register and pc(jump to ISR)MENDIMPORT  |Image$$RO$$Limit|  ;// End of ROM code (=start of ROM data)IMPORT  |Image$$RW$$Base|   ;// Base of RAM to initialiseIMPORT  |Image$$ZI$$Base|   ;// Base and limit of areaIMPORT  |Image$$ZI$$Limit|  ;// to zero initialise;//IMPORT  Main    ;// The main entry of mon program AREA    Init,CODE,READONLYENTRY ; //1)The code, which converts to Big-endian, should be in little endian code.; //2)The following little endian code will be compiled in Big-Endian mode. ; //  The code byte order should be changed as the memory bus width.; //3)The pseudo instruction,DCD can"t be used here because the linker generates error.ASSERT:DEF:ENDIAN_CHANGE[ ENDIAN_CHANGE    ASSERT  :DEF:ENTRY_BUS_WIDTH    [ ENTRY_BUS_WIDTH=32bChangeBigEndian    ;//DCD 0xea000007     ]        [ ENTRY_BUS_WIDTH=16andeqr14,r7,r0,lsl #20   ;//DCD 0x0007ea00    ]        [ ENTRY_BUS_WIDTH=8streqr0,[r0,-r10,ror #1] ;//DCD 0x070000ea            ]|    bResetHandler      ]bHandlerUndef;//handler for Undefined modebHandlerSWI;//handler for SWI interruptbHandlerPabort;//handler for PAbortbHandlerDabort;//handler for DAbortb.;//reservedbHandlerIRQ;//handler for IRQ interrupt bHandlerFIQ;//handler for FIQ interrupt;//@0x20bEnterPWDNChangeBigEndian;//@0x24[ ENTRY_BUS_WIDTH=32    DCD0xee110f10;//0xee110f10 => mrc p15,0,r0,c1,c0,0    DCD0xe3800080;//0xe3800080 => orr r0,r0,#0x80;  //Big-endian    DCD0xee010f10;//0xee010f10 => mcr p15,0,r0,c1,c0,0][ ENTRY_BUS_WIDTH=16    DCD 0x0f10ee11    DCD 0x0080e380    DCD 0x0f10ee01][ ENTRY_BUS_WIDTH=8    DCD 0x100f11ee    DCD 0x800080e3    DCD 0x100f01ee    ]DCD 0xffffffff  ;//swinv 0xffffff is similar with NOP and run well in both endian mode. DCD 0xffffffffDCD 0xffffffffDCD 0xffffffffDCD 0xffffffffb ResetHandler;//Function for entering power down mode;// 1. SDRAM should be in self-refresh mode.;// 2. All interrupt should be maksked for SDRAM/DRAM self-refresh.;// 3. LCD controller should be disabled for SDRAM/DRAM self-refresh.;// 4. The I-cache may have to be turned on. ;// 5. The location of the following code may have not to be changed.;//void EnterPWDN(int CLKCON); EnterPWDNmov r2,r0;//r2=rCLKCONtst r0,#0x8;//POWER_OFF mode?bne ENTER_POWER_OFFENTER_STOPldr r0,=REFRESHldr r3,[r0];//r3=rREFRESHmov r1, r3orr r1, r1, #BIT_SELFREFRESHstr r1, [r0];//Enable SDRAM self-refreshmov r1,#16   ;//wait until self-refresh is issued. may not be needed.0subs r1,r1,#1bne %B0ldr r0,=CLKCON;//enter STOP mode.str r2,[r0]    mov r1,#320subs r1,r1,#1;//1) wait until the STOP mode is in effect.bne %B0;//2) Or wait here until the CPU&Peripherals will be turned-off;//   Entering POWER_OFF mode, only the reset by wake-up is available.ldr r0,=REFRESH ;//exit from SDRAM self refresh mode.str r3,[r0]MOV_PC_LRENTER_POWER_OFF;//NOTE.;//1) rGSTATUS3 should have the return address after wake-up from POWER_OFF mode.ldr r0,=REFRESHldr r1,[r0];r1=rREFRESHorr r1, r1, #BIT_SELFREFRESHstr r1, [r0];//Enable SDRAM self-refreshmov r1,#16   ;//Wait until self-refresh is issued,which may not be needed.0subs r1,r1,#1bne %B0ldr r1,=MISCCRldrr0,[r1]orrr0,r0,#(7<<17)  ;//Make sure that SCLK0:SCLK->0, SCLK1:SCLK->0, SCKE=L during boot-up strr0,[r1]ldr r0,=CLKCONstr r2,[r0]    b .;//CPU will die here.WAKEUP_POWER_OFF;//Release SCLKn after wake-up from the POWER_OFF mode.ldr r1,=MISCCRldrr0,[r1]bicr0,r0,#(7<<17)  ;//SCLK0:0->SCLK, SCLK1:0->SCLK, SCKE:L->Hstrr0,[r1];//Set memory control registers    ldrr0,=SMRDATAldrr1,=BWSCON;//BWSCON Addressaddr2, r0, #52;//End address of SMRDATA0       ldrr3, [r0], #4    strr3, [r1], #4    cmpr2, r0bne%B0mov r1,#2560subs r1,r1,#1;//1) wait until the SelfRefresh is released.bne %B0ldr r1,=GSTATUS3 ;//GSTATUS3 has the start address just after POWER_OFF wake-upldr r0,[r1]mov pc,r0LTORG   HandlerFIQ      HANDLER HandleFIQHandlerIRQ      HANDLER HandleIRQHandlerUndef    HANDLER HandleUndefHandlerSWI      HANDLER HandleSWIHandlerDabort   HANDLER HandleDabortHandlerPabort   HANDLER HandlePabortIsrIRQ  subsp,sp,#4       ;//reserved for PCstmfdsp!,{r8-r9}   ldrr9,=INTOFFSETldrr9,[r9]ldrr8,=HandleEINT0addr8,r8,r9,lsl #2ldrr8,[r8]strr8,[sp,#8]ldmfdsp!,{r8-r9,pc};//====================================================================;// ENTRY  ;//===================================================================ResetHandlerldrr0,=WTCON       ;//watch dog disable ldrr1,=0x0         strr1,[r0]ldrr0,=INTMSKldrr1,=0xffffffff  ;//all interrupt disablestrr1,[r0]ldrr0,=INTSUBMSKldrr1,=0x7ff;//all sub interrupt disable, 2002/04/10strr1,[r0][ {FALSE}        ;// rGPFDAT = (rGPFDAT & ~(0xf<<4)) | ((~data & 0xf)<<4);            ;// Led_Displayldrr0,=GPFCONldrr1,=0x5500strr1,[r0]ldrr0,=GPFDATldrr1,=0x10strr1,[r0]];//To reduce PLL lock time, adjust the LOCKTIME register. ldrr0,=LOCKTIMEldrr1,=0xffffffstrr1,[r0]            [ PLL_ON_START;//Configure MPLLldrr0,=MPLLCON          ldrr1,=((0xa1<<12)+(3<<4)+0x1)  ;//Fin=12MHz,Fout=50MHzstrr1,[r0]];//Check if the boot is caused by the wake-up from POWER_OFF mode.ldrr1,=GSTATUS2ldrr0,[r1]tstr0,#0x2        ;//In case of the wake-up from POWER_OFF mode, go to POWER_OFF_WAKEUP handler. bneWAKEUP_POWER_OFFEXPORT StartPointAfterPowerOffWakeUpStartPointAfterPowerOffWakeUp;//Set memory control registers    ldrr0,=SMRDATAldrr1,=BWSCON;//BWSCON Addressaddr2, r0, #52;//End address of SMRDATA0       ldrr3, [r0], #4    strr3, [r1], #4    cmpr2, r0bne%B0    ;//Initialize stacksblInitStacks  ;// Setup IRQ handlerldrr0,=HandleIRQ       ;//This routine is neededldrr1,=IsrIRQ          ;//if there isn"t "subs pc,lr,#4" at 0x18, 0x1cstrr1,[r0];//Copy and paste RW data/zero initialized dataldrr0, =|Image$$RO$$Limit| ; Get pointer to ROM dataldrr1, =|Image$$RW$$Base|  ; and RAM copyldrr3, =|Image$$ZI$$Base|  ;//Zero init base => top of initialised datacmpr0, r1      ;// Check that they are differentbeq%F21       cmpr1, r3      ;// Copy init dataldrccr2, [r0], #4    ;//--> LDRCC r2, [r0] + ADD r0, r0, #4         strccr2, [r1], #4    ;//--> STRCC r2, [r1] + ADD r1, r1, #4bcc%B12       ldrr1, =|Image$$ZI$$Limit| ;// Top of zero init segmentmovr2, #03       cmpr3, r1      ;// Zero initstrccr2, [r3], #4bcc%B3;//呼叫主应用程序b UARTUART    ldr r0, =GPHCON ;//设置RxD0,TxD0引脚    ldr r1, =0x2afaaa    str r1, [r0]        ldr r0, =GPHUP    ldr r1, =0x7ff    str r1, [r0] ;    // The pull up function is disabled GPH[10:0]    ldr r0, =UFCON0 ;//禁用FIFO    ldr r1, =0x0    str r1, [r0]       ldr r0, =UMCON0  ;//禁用AFC    ldr r1, =0x0    str r1, [r0]        ldr r0, =ULCON0 ;//设置线寄存器    ldr r1, =0x3   ; //UART LINE CONFIG  正常模式,无奇偶校验,一个停止位,8个数据位    str r1, [r0]        ldr r0, =UCON0 ;//设置Uart0控制器    ldr r1, =0x245;//RX边沿触发,TX电平触发,禁用延时中断,使用RX 错误中断,正常操作模式,中断请求或表决模式    str r1, [r0]        ldr r0, =UBRDIV0 ;//设置波特率为115200    ldr r1, =0x1a    ;//int(50700000 / 16 / 115200) - 1 = 26    str r1, [r0]        mov r1, #100Delay    sub r1, r1, #0x1    bne Delay        ;//开中断    ldr r0, =INTMSK    ldr r1, [r0]    and r1, r1, #0xefffffff    str r1, [r0]        MOV R5 , #127 ;//设置要打印的字符的个数    MOV R1 , #0x0 ;//设置要打印的字符LOOP     LDR R3 , =UTRSTAT0   LDR R2 , [R3]   TST R2 ,#0x04 ;//判断发送缓冲区是否为空   BEQ LOOP      ;//为空则执行下边的语句，不为空则跳转到LOOP   LDR R0 , =UTXH0      STR R1 ,[R0] ;//向数据缓冲区放置要发送的数据   ADD R1, R1, #1   SUB R5 ,R5, #0x01 ;//计数器减一   CMP R5 ,#0x0   BNE LOOP  LOOP2   B LOOP2 ;    /*;    pclk    = PCLK;;    rUFCON0 = 0x0;   //UART channel 0 FIFO control register, FIFO disable;    rUFCON1 = 0x0;   //UART channel 1 FIFO control register, FIFO disable;    rUFCON2 = 0x0;   //UART channel 2 FIFO control register, FIFO disable;    rUMCON0 = 0x0;   //UART chaneel 0 MODEM control register, AFC disable;    rUMCON1 = 0x0;   //UART chaneel 1 MODEM control register, AFC disable    ;//UART0;    rULCON0 = 0x3;   //Line control register : Normal,No parity,1 stop,8 bits;     //    [10]       [9]     [8]        [7]        [6]      [5]         [4]           [3:2]        [1:0];     // Clock Sel,  Tx Int,  Rx Int, Rx Time Out, Rx err, Loop-back, Send break,  Transmit Mode, Receive Mode;     //     0          1       0    ,     0          1        0           0     ,       01          01;     //   PCLK       Level    Pulse    Disable    Generate  Normal      Normal        Interrupt or Polling;    rUCON0  = 0x245;                        // Control register;//    rUBRDIV0=( (int)(pclk/16./baud) -1 );   //Baud rate divisior register 0;    rUBRDIV0=( (int)(pclk/16./baud+0.5) -1 );   //Baud rate divisior register 0        ;//UART1;    rULCON1 = 0x3;;    rUCON1  = 0x245;;    rUBRDIV1=( (int)(pclk/16./baud) -1 );;    ;//UART2;    rULCON2 = 0x3;;    rUCON2  = 0x245;;    rUBRDIV2=( (int)(pclk/16./baud) -1 );    ;;    for(i=0;i<100;i++);;    ;    */;//END OF UART HERE;//function initializing stacksInitStacks;//Don"t use DRAM,such as stmfd,ldmfd......;//SVCstack is initialized before;//Under toolkit ver 2.5, "msr cpsr,r1" can be used instead of "msr cpsr_cxsf,r1"mrsr0,cpsrbicr0,r0,#MODEMASKorrr1,r0,#UNDEFMODE|NOINTmsrcpsr_cxsf,r1;//UndefModeldrsp,=UndefStackorrr1,r0,#ABORTMODE|NOINTmsrcpsr_cxsf,r1;//AbortModeldrsp,=AbortStackorrr1,r0,#IRQMODE|NOINTmsrcpsr_cxsf,r1;//IRQModeldrsp,=IRQStack    orrr1,r0,#FIQMODE|NOINTmsrcpsr_cxsf,r1;//FIQModeldrsp,=FIQStackbicr0,r0,#MODEMASK|NOINTorrr1,r0,#SVCMODEmsrcpsr_cxsf,r1;//SVCModeldrsp,=SVCStack;//USER mode has not be initialized.movpc,lr ;//The LR register won"t be valid if the current mode is not SVC mode.LTORG; incbin ..\..\Font\Hzk16.binSMRDATA DATA;// Memory configuration should be optimized for best performance ;// The following parameter is not optimized.                     ;// Memory access cycle parameter strategy;// 1) The memory settings is  safe parameters even at HCLK=75Mhz.;// 2) SDRAM refresh period is for HCLK=75Mhz.         DCD (0+(B1_BWSCON<<4)+(B2_BWSCON<<8)+(B3_BWSCON<<12)+(B4_BWSCON<<16)+(B5_BWSCON<<20)+(B6_BWSCON<<24)+(B7_BWSCON<<28))    DCD ((B0_Tacs<<13)+(B0_Tcos<<11)+(B0_Tacc<<8)+(B0_Tcoh<<6)+(B0_Tah<<4)+(B0_Tacp<<2)+(B0_PMC))   ;//GCS0    DCD ((B1_Tacs<<13)+(B1_Tcos<<11)+(B1_Tacc<<8)+(B1_Tcoh<<6)+(B1_Tah<<4)+(B1_Tacp<<2)+(B1_PMC))   ;//GCS1     DCD ((B2_Tacs<<13)+(B2_Tcos<<11)+(B2_Tacc<<8)+(B2_Tcoh<<6)+(B2_Tah<<4)+(B2_Tacp<<2)+(B2_PMC))   ;//GCS2    DCD ((B3_Tacs<<13)+(B3_Tcos<<11)+(B3_Tacc<<8)+(B3_Tcoh<<6)+(B3_Tah<<4)+(B3_Tacp<<2)+(B3_PMC))   ;//GCS3    DCD ((B4_Tacs<<13)+(B4_Tcos<<11)+(B4_Tacc<<8)+(B4_Tcoh<<6)+(B4_Tah<<4)+(B4_Tacp<<2)+(B4_PMC))   ;//GCS4    DCD ((B5_Tacs<<13)+(B5_Tcos<<11)+(B5_Tacc<<8)+(B5_Tcoh<<6)+(B5_Tah<<4)+(B5_Tacp<<2)+(B5_PMC))   ;//GCS5    DCD ((B6_MT<<15)+(B6_Trcd<<2)+(B6_SCAN))    ;//GCS6    DCD ((B7_MT<<15)+(B7_Trcd<<2)+(B7_SCAN))    ;//GCS7    DCD ((REFEN<<23)+(TREFMD<<22)+(Trp<<20)+(Trc<<18)+(Tchr<<16)+REFCNT)    DCD 0x32            ;//SCLK power saving mode, BANKSIZE 128M/128M    DCD 0x30            ;//MRSR6 CL=3clk    DCD 0x30            ;//MRSR7;//    DCD 0x20            ;//MRSR6 CL=2clk;///   DCD 0x20            ;//MRSR7    ALIGN    AREA RamData, DATA, READWRITE        ^   _ISR_STARTADDRESSHandleReset #   4HandleUndef #   4HandleSWI   #   4HandlePabort    #   4HandleDabort    #   4HandleReserved  #   4HandleIRQ   #   4HandleFIQ   #   4;//Don"t use the label "IntVectorTable",;//The value of IntVectorTable is different with the address you think it may be.;//IntVectorTableHandleEINT0   #   4HandleEINT1   #   4HandleEINT2   #   4HandleEINT3   #   4HandleEINT4_7#   4HandleEINT8_23#   4HandleRSV6#   4HandleBATFLT   #   4HandleTICK   #   4HandleWDT#   4HandleTIMER0 #   4HandleTIMER1 #   4HandleTIMER2 #   4HandleTIMER3 #   4HandleTIMER4 #   4HandleUART2  #   4HandleLCD #   4HandleDMA0#   4HandleDMA1#   4HandleDMA2#   4HandleDMA3#   4HandleMMC#   4HandleSPI0#   4HandleUART1#   4HandleRSV24#   4HandleUSBD#   4HandleUSBH#   4HandleIIC   #   4HandleUART0 #   4HandleSPI1 #   4HandleRTC #   4HandleADC #   4        END