新版的MDK支持2440相关芯片,但是很多人的工程都是基于ADS1.2开发,文字不好看,兼容性不好等等问题,而且电脑上装太多开发工具切换起来也麻烦,所以切换到MDK开发2440裸机程序应该是一个很好的选择
1. 新建MDK工程,芯片选择2440
不拷贝启动代码,因为我们用自己的启动代码
2. 建立工程目录分级,建立完成后如下所示
拷贝相应代码到对应目录中
Option中拷贝
Core中拷贝
建立新的main文件
将文件加入工程
路径中建立包含
还要为asm文件建立包含
修改2440init.s文件
首先,MDK默认放在最前面的段是RESET段,将2440init.s第84行(可能你的不是) AREA Init,CODE,READONLY修改为 AREA RESET,CODE,READONLY
这样编译器就能找到入口点了
在上面这句下面加上一行
PRESERVE8 ;8 字对齐(为了让汇编代码8字节对齐)
修改
IMPORT |Image$$RO$$Base| ; Base of ROM code
IMPORT |Image$$RO$$Limit| ; End of ROM code (=start of ROM data)
IMPORT |Image$$RW$$Base| ; Base of RAM to initialise
IMPORT |Image$$ZI$$Base| ; Base and limit of area
IMPORT |Image$$ZI$$Limit| ; to zero initialise
这些是通过ADS的工程设置里面设定的RO Base和RW Base设定的,在MDK中的名称不叫这个
修改为
IMPORT |Image$$ER_ROM1$$RO$$Base| ; Base of ROM code
IMPORT |Image$$ER_ROM1$$RO$$Limit| ; End of ROM code (=start of ROM data)
IMPORT |Image$$RW_RAM1$$RW$$Base| ; Base of RAM to initialise
IMPORT |Image$$RW_RAM1$$ZI$$Base| ; Base and limit of area
IMPORT |Image$$RW_RAM1$$ZI$$Limit| ; to zero initialize
上面的改了下面的这个也要改
BaseOfROM DCD |Image$$RO$$Base|
TopOfROM DCD |Image$$RO$$Limit|
BaseOfBSS DCD |Image$$RW$$Base|
BaseOfZero DCD |Image$$ZI$$Base|
EndOfBSS DCD |Image$$ZI$$Limit|
修改为
BaseOfROM DCD |Image$$ER_ROM1$$RO$$Base|
TopOfROM DCD |Image$$ER_ROM1$$RO$$Limit|
BaseOfBSS DCD |Image$$RW_RAM1$$RW$$Base|
BaseOfZero DCD |Image$$RW_RAM1$$ZI$$Base|
EndOfBSS DCD |Image$$RW_RAM1$$ZI$$Limit|
此时还需要设置代码运行区和存放区
ROM区域需要打开nand.c中的RdNF2SDRAM函数查看起始地址
我的起始地址为0x30000000 大小为0x100000
Size必须大于0x100000,RAM空间大于ROM空间且少于最大物理空间即可(不要忘了打钩勾)
编写Main函数,记住是首字母大写
此时编译就可以通过了
随意将一个ADS1.2编写好的led驱动放进去,最终修改如下
Led.h
#ifndef __LED_H #define __LED_H #include "2440addr.h" typedef enum { LED1 = 0, //GPB5 LED2 = 1, //GPB6 LED3 = 2, //GPB5 LED4 = 3 //GPB8 }LEDn; void ledInit(LEDn led); void ledInitAll(void); void ledOn(LEDn led); void ledOff(LEDn led); void ledTurn(LEDn led); unsigned char getLedStatus(LEDn led); //TQ2440led引脚 B5 B6 B7 B8 #endif
Led.c
#include "led.h" void ledInit(LEDn led) { if(led == LED1) { rGPBCON &= ~(3<<10); //端口写入01设置为输出模式,先清零 rGPBCON |= (1<<10); //设置为输出 rGPBUP &= ~(1<<5); //禁止上拉 rGPBDAT |= (1<<5); //设置初始值为1,灯灭 } else if(led == LED2) { rGPBCON &= ~(3<<12); rGPBCON |= (1<<12); rGPBUP &= ~(1<<6); rGPBDAT |= (1<<6); } else if(led == LED3) { rGPBCON &= ~(3<<14); rGPBCON |= (1<<14); rGPBUP &= ~(1<<7); rGPBDAT |= (1<<7); } else if(led == LED4) { rGPBCON &= ~(3<<16); rGPBCON |= (1<<16); rGPBUP &= ~(1<<8); rGPBDAT |= (1<<8); } } void ledInitAll(void) { rGPBCON &=~((3<<10)|(3<<12)|(3<<14)|(3<<16)); //对GPBCON[10:17]清零 rGPBCON |=((1<<10)|(1<<12)|(1<<14)|(1<<16)); //设置GPB5~8为输出 rGPBUP &=~((1<<5)|(1<<6)|(1<<7)|(1<<8)); //设置GPB5~8的上拉功能 rGPBDAT |=(1<<5)|(1<<6)|(1<<7)|(1<<8); //关闭LED } void ledOn(LEDn led) { rGPBDAT &= ~(1<<(5+led)); } void ledOff(LEDn led) { rGPBDAT |= (1<<(5+led)); } void ledTurn(LEDn led) { if(getLedStatus(led))ledOn(led); else ledOff(led); } unsigned char getLedStatus(LEDn led)//获取led状态,灭为1亮为0 { if((rGPBDAT & (1<<(5+led))))return 1; else return 0; }
Main.c
#include "2440addr.h" #include "led.h" void Delay(void) { int i; for(i=0;i<1000000;i++); } int Main() { ledInitAll(); while(1) { ledTurn(LED1); Delay(); ledTurn(LED2); Delay(); ledTurn(LED3); Delay(); ledTurn(LED4); Delay(); } }
最后编译,结果如下
但是生成的是HEX,我们需要指令转换成BIN文件
在这里写入指令
记住对勾!
编译,提示如下
BIN文件生成OK了
下载进去,流水灯完全正常,收工!
最后附带修改好了2440init.s文件
2440init.s
;========================================= ; NAME: 2440INIT.S ; DESC: C start up codes ; Configure memory, ISR ,stacks ; Initialize C-variables ;========================================= GET option.inc GET memcfg.inc GET 2440addr.inc BIT_SELFREFRESH EQU (1<<22) ;Pre-defined constants USERMODE EQU 0x10 FIQMODE EQU 0x11 IRQMODE EQU 0x12 SVCMODE EQU 0x13 ABORTMODE EQU 0x17 UNDEFMODE EQU 0x1b MODEMASK EQU 0x1f NOINT EQU 0xc0 ;The location of stacks UserStack 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} ] MACRO MOV_PC_LR [ THUMBCODE bx lr | mov pc,lr ] MEND MACRO MOVEQ_PC_LR [ THUMBCODE bxeq lr | moveq pc,lr ] MEND MACRO $HandlerLabel HANDLER $HandleLabel $HandlerLabel sub sp,sp,#4 ;decrement sp(to store jump address) stmfd sp!,{r0} ;PUSH the work register to stack(lr does not push because it return to original address) ldr r0,=$HandleLabel;load the address of HandleXXX to r0 ldr r0,[r0] ;load the contents(service routine start address) of HandleXXX str r0,[sp,#4] ;store the contents(ISR) of HandleXXX to stack ldmfd sp!,{r0,pc} ;POP the work register and pc(jump to ISR) MEND IMPORT |Image$$ER_ROM1$$RO$$Base| ; Base of ROM code IMPORT |Image$$ER_ROM1$$RO$$Limit| ; End of ROM code (=start of ROM data) IMPORT |Image$$RW_RAM1$$RW$$Base| ; Base of RAM to initialise IMPORT |Image$$RW_RAM1$$ZI$$Base| ; Base and limit of area IMPORT |Image$$RW_RAM1$$ZI$$Limit| ; to zero initialise IMPORT MMU_SetAsyncBusMode IMPORT MMU_SetFastBusMode ; IMPORT Main ; The main entry of mon program IMPORT RdNF2SDRAM ; Copy Image from Nand Flash to SDRAM AREA RESET,CODE,READONLY PRESERVE8 ;8 字对齐 ENTRY EXPORT __ENTRY __ENTRY ResetEntry ;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 not be used here because the linker generates error. ASSERT :DEF:ENDIAN_CHANGE [ ENDIAN_CHANGE ASSERT :DEF:ENTRY_BUS_WIDTH [ ENTRY_BUS_WIDTH=32 b ChangeBigEndian ;DCD 0xea000007 ] [ ENTRY_BUS_WIDTH=16 andeq r14,r7,r0,lsl #20 ;DCD 0x0007ea00 ] [ ENTRY_BUS_WIDTH=8 streq r0,[r0,-r10,ror #1] ;DCD 0x070000ea ] | b ResetHandler ] b HandlerUndef ;handler for Undefined mode b HandlerSWI ;handler for SWI interrupt b HandlerPabort ;handler for PAbort b HandlerDabort ;handler for DAbort b . ;reserved b HandlerIRQ ;handler for IRQ interrupt b HandlerFIQ ;handler for FIQ interrupt ;@0x20 b EnterPWDN ; Must be @0x20. ChangeBigEndian ;@0x24 [ ENTRY_BUS_WIDTH=32 DCD 0xee110f10 ;0xee110f10 => mrc p15,0,r0,c1,c0,0 DCD 0xe3800080 ;0xe3800080 => orr r0,r0,#0x80; //Big-endian DCD 0xee010f10 ;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 0xffffffff DCD 0xffffffff DCD 0xffffffff DCD 0xffffffff b ResetHandler HandlerFIQ HANDLER HandleFIQ HandlerIRQ HANDLER HandleIRQ HandlerUndef HANDLER HandleUndef HandlerSWI HANDLER HandleSWI HandlerDabort HANDLER HandleDabort HandlerPabort HANDLER HandlePabort IsrIRQ sub sp,sp,#4 ;reserved for PC stmfd sp!,{r8-r9} ldr r9,=INTOFFSET ldr r9,[r9] ldr r8,=HandleEINT0 add r8,r8,r9,lsl #2 ldr r8,[r8] str r8,[sp,#8] ldmfd sp!,{r8-r9,pc} LTORG ;======= ; ENTRY ;======= ResetHandler ldr r0,=WTCON ;watch dog disable ldr r1,=0x0 str r1,[r0] ldr r0,=INTMSK ldr r1,=0xffffffff ;all interrupt disable str r1,[r0] ldr r0,=INTSUBMSK ldr r1,=0x7fff ;all sub interrupt disable str r1,[r0] [ {FALSE} ; GPBDAT = (rGPFDAT & ~(0xf<<4)) | ((~data & 0xf)<<4); ; Led_Display ldr r0,=GPBCON ldr r1,=0x00555555 str r1,[r0] ldr r0,=GPBDAT ldr r1,=0x07fe str r1,[r0] ] ;To reduce PLL lock time, adjust the LOCKTIME register. ldr r0,=LOCKTIME ldr r1,=0xffffff str r1,[r0] [ PLL_ON_START ; Added for confirm clock divide. for 2440. ; Setting value Fclk:Hclk:Pclk ldr r0,=CLKDIVN ldr r1,=CLKDIV_VAL ; 0=1:1:1, 1=1:1:2, 2=1:2:2, 3=1:2:4, 4=1:4:4, 5=1:4:8, 6=1:3:3, 7=1:3:6. str r1,[r0] ;program has not been copied, so use these directly [ CLKDIV_VAL>1 ; means Fclk:Hclk is not 1:1. mrc p15,0,r0,c1,c0,0 orr r0,r0,#0xc0000000;R1_nF:OR:R1_iA mcr p15,0,r0,c1,c0,0 | mrc p15,0,r0,c1,c0,0 bic r0,r0,#0xc0000000;R1_iA:OR:R1_nF mcr p15,0,r0,c1,c0,0 ] ;Configure UPLL ldr r0,=UPLLCON ldr r1,=((U_MDIV<<12)+(U_PDIV<<4)+U_SDIV) ;Fin = 12.0MHz, UCLK = 48MHz str r1,[r0] nop ; Caution: After UPLL setting, at least 7-clocks delay must be inserted for setting hardware be completed. nop nop nop nop nop nop ;Configure MPLL ldr r0,=MPLLCON ldr r1,=((M_MDIV<<12)+(M_PDIV<<4)+M_SDIV) ;Fin = 12.0MHz, FCLK = 400MHz str r1,[r0] ] ;Check if the boot is caused by the wake-up from SLEEP mode. ldr r1,=GSTATUS2 ldr r0,[r1] tst r0,#0x2 ;In case of the wake-up from SLEEP mode, go to SLEEP_WAKEUP handler. bne WAKEUP_SLEEP EXPORT StartPointAfterSleepWakeUp StartPointAfterSleepWakeUp ;Set memory control registers adrl r0,SMRDATA ldr r1,=BWSCON ;BWSCON Address add r2, r0, #52 ;End address of SMRDATA 0 ldr r3, [r0], #4 str r3, [r1], #4 cmp r2, r0 bne %B0 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;;;;;;;;;;;; When EINT0 is pressed, Clear SDRAM ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; check if EIN0 button is pressed ldr r0,=GPFCON ldr r1,=0x0 str r1,[r0] ldr r0,=GPFUP ldr r1,=0xff str r1,[r0] ldr r1,=GPFDAT ldr r0,[r1] bic r0,r0,#(0x1e<<1) ; bit clear tst r0,#0x1 bne %F1 ; Clear SDRAM Start ldr r0,=GPFCON ldr r1,=0x55aa str r1,[r0] ldr r0,=GPFDAT ldr r1,=0x0 str r1,[r0] ;LED=**** mov r1,#0 mov r2,#0 mov r3,#0 mov r4,#0 mov r5,#0 mov r6,#0 mov r7,#0 mov r8,#0 ldr r9,=0x4000000 ;64MB ldr r0,=0x30000000 0 stmia r0!,{r1-r8} subs r9,r9,#32 bne %B0 ;Clear SDRAM End 1 ;Initialize stacks bl InitStacks ;=========================================================== ldr r0, =BWSCON ldr r0, [r0] ands r0, r0, #6 ;OM[1:0] != 0, NOR FLash boot bne copy_proc_beg ;do not read nand flash adr r0, ResetEntry ;OM[1:0] == 0, NAND FLash boot cmp r0, #0 ;if use Multi-ice, bne copy_proc_beg ;do not read nand flash for boot ;nop ;=========================================================== nand_boot_beg [ {TRUE} bl RdNF2SDRAM ] ldr pc, =copy_proc_beg ;=========================================================== copy_proc_beg adr r0, ResetEntry ldr r2, BaseOfROM cmp r0, r2 ldreq r0, TopOfROM beq InitRam ldr r3, TopOfROM 0 ldmia r0!, {r4-r7} stmia r2!, {r4-r7} cmp r2, r3 bcc %B0 sub r2, r2, r3 sub r0, r0, r2 InitRam ldr r2, BaseOfBSS ldr r3, BaseOfZero 0 cmp r2, r3 ldrcc r1, [r0], #4 strcc r1, [r2], #4 bcc %B0 mov r0, #0 ldr r3, EndOfBSS 1 cmp r2, r3 strcc r0, [r2], #4 bcc %B1 ldr pc, =%F2 ;goto compiler address 2 ; [ CLKDIV_VAL>1 ; means Fclk:Hclk is not 1:1. ; bl MMU_SetAsyncBusMode ; | ; bl MMU_SetFastBusMode ; default value. ; ] ;=========================================================== ; Setup IRQ handler ldr r0,=HandleIRQ ;This routine is needed ldr r1,=IsrIRQ ;if there is not 'subs pc,lr,#4' at 0x18, 0x1c str r1,[r0] [ :LNOT:THUMBCODE bl Main ;Do not use main() because ...... b . ] [ THUMBCODE ;for start-up code for Thumb mode orr lr,pc,#1 bx lr CODE16 bl Main ;Do not use main() because ...... b . CODE32 ] ;function initializing stacks InitStacks ;Do not 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' mrs r0,cpsr bic r0,r0,#MODEMASK orr r1,r0,#UNDEFMODE:OR:NOINT msr cpsr_cxsf,r1 ;UndefMode ldr sp,=UndefStack ; UndefStack=0x33FF_5C00 orr r1,r0,#ABORTMODE:OR:NOINT msr cpsr_cxsf,r1 ;AbortMode ldr sp,=AbortStack ; AbortStack=0x33FF_6000 orr r1,r0,#IRQMODE:OR:NOINT msr cpsr_cxsf,r1 ;IRQMode ldr sp,=IRQStack ; IRQStack=0x33FF_7000 orr r1,r0,#FIQMODE:OR:NOINT msr cpsr_cxsf,r1 ;FIQMode ldr sp,=FIQStack ; FIQStack=0x33FF_8000 bic r0,r0,#MODEMASK:OR:NOINT orr r1,r0,#SVCMODE msr cpsr_cxsf,r1 ;SVCMode ldr sp,=SVCStack ; SVCStack=0x33FF_5800 ;USER mode has not be initialized. mov pc,lr ;The LR register will not be valid if the current mode is not SVC mode. LTORG SMRDATA 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)+(Tsrc<<18)+(Tchr<<16)+REFCNT) DCD 0x32 ;SCLK power saving mode, BANKSIZE 128M/128M DCD 0x30 ;MRSR6 CL=3clk DCD 0x30 ;MRSR7 CL=3clk BaseOfROM DCD |Image$$ER_ROM1$$RO$$Base| TopOfROM DCD |Image$$ER_ROM1$$RO$$Limit| BaseOfBSS DCD |Image$$RW_RAM1$$RW$$Base| BaseOfZero DCD |Image$$RW_RAM1$$ZI$$Base| EndOfBSS DCD |Image$$RW_RAM1$$ZI$$Limit| ALIGN ;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); EnterPWDN mov r2,r0 ;r2=rCLKCON tst r0,#0x8 ;SLEEP mode? bne ENTER_SLEEP ENTER_STOP ldr r0,=REFRESH ldr r3,[r0] ;r3=rREFRESH mov r1, r3 orr r1, r1, #BIT_SELFREFRESH str r1, [r0] ;Enable SDRAM self-refresh mov r1,#16 ;wait until self-refresh is issued. may not be needed. 0 subs r1,r1,#1 bne %B0 ldr r0,=CLKCON ;enter STOP mode. str r2,[r0] mov r1,#32 0 subs 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 SLEEP mode, only the reset by wake-up is available. ldr r0,=REFRESH ;exit from SDRAM self refresh mode. str r3,[r0] MOV_PC_LR ENTER_SLEEP ;NOTE. ;1) rGSTATUS3 should have the return address after wake-up from SLEEP mode. ldr r0,=REFRESH ldr r1,[r0] ;r1=rREFRESH orr r1, r1, #BIT_SELFREFRESH str r1, [r0] ;Enable SDRAM self-refresh mov r1,#16 ;Wait until self-refresh is issued,which may not be needed. 0 subs r1,r1,#1 bne %B0 ldr r1,=MISCCR ldr r0,[r1] orr r0,r0,#(7<<17) ;Set SCLK0=0, SCLK1=0, SCKE=0. str r0,[r1] ldr r0,=CLKCON ; Enter sleep mode str r2,[r0] b . ;CPU will die here. WAKEUP_SLEEP ;Release SCLKn after wake-up from the SLEEP mode. ldr r1,=MISCCR ldr r0,[r1] bic r0,r0,#(7<<17) ;SCLK0:0->SCLK, SCLK1:0->SCLK, SCKE:0->=SCKE. str r0,[r1] ;Set memory control registers ldr r0,=SMRDATA ldr r1,=BWSCON ;BWSCON Address add r2, r0, #52 ;End address of SMRDATA 0 ldr r3, [r0], #4 str r3, [r1], #4 cmp r2, r0 bne %B0 mov r1,#256 0 subs r1,r1,#1 ;1) wait until the SelfRefresh is released. bne %B0 ldr r1,=GSTATUS3 ;GSTATUS3 has the start address just after SLEEP wake-up ldr r0,[r1] mov pc,r0 ;===================================================================== ; Clock division test ; Assemble code, because VSYNC time is very short ;===================================================================== EXPORT CLKDIV124 EXPORT CLKDIV144 CLKDIV124 ldr r0, = CLKDIVN ldr r1, = 0x3 ; 0x3 = 1:2:4 str r1, [r0] ; wait until clock is stable nop nop nop nop nop ldr r0, = REFRESH ldr r1, [r0] bic r1, r1, #0xff bic r1, r1, #(0x7<<8) orr r1, r1, #0x470 ; REFCNT135 str r1, [r0] nop nop nop nop nop mov pc, lr CLKDIV144 ldr r0, = CLKDIVN ldr r1, = 0x4 ; 0x4 = 1:4:4 str r1, [r0] ; wait until clock is stable nop nop nop nop nop ldr r0, = REFRESH ldr r1, [r0] bic r1, r1, #0xff bic r1, r1, #(0x7<<8) orr r1, r1, #0x630 ; REFCNT675 - 1520 str r1, [r0] nop nop nop nop nop mov pc, lr ALIGN AREA RamData, DATA, READWRITE ^ _ISR_STARTADDRESS ; _ISR_STARTADDRESS=0x33FF_FF00 HandleReset # 4 HandleUndef # 4 HandleSWI # 4 HandlePabort # 4 HandleDabort # 4 HandleReserved # 4 HandleIRQ # 4 HandleFIQ # 4 ;Do not use the label 'IntVectorTable', ;The value of IntVectorTable is different with the address you think it may be. ;IntVectorTable ;@0x33FF_FF20 HandleEINT0 # 4 HandleEINT1 # 4 HandleEINT2 # 4 HandleEINT3 # 4 HandleEINT4_7 # 4 HandleEINT8_23 # 4 HandleCAM # 4 ; Added for 2440. HandleBATFLT # 4 HandleTICK # 4 HandleWDT # 4 HandleTIMER0 # 4 HandleTIMER1 # 4 HandleTIMER2 # 4 HandleTIMER3 # 4 HandleTIMER4 # 4 HandleUART2 # 4 ;@0x33FF_FF60 HandleLCD # 4 HandleDMA0 # 4 HandleDMA1 # 4 HandleDMA2 # 4 HandleDMA3 # 4 HandleMMC # 4 HandleSPI0 # 4 HandleUART1 # 4 HandleNFCON # 4 ; Added for 2440. HandleUSBD # 4 HandleUSBH # 4 HandleIIC # 4 HandleUART0 # 4 HandleSPI1 # 4 HandleRTC # 4 HandleADC # 4 ;@0x33FF_FFA0 END