Mode_User     equ 0x10
I_Bit         equ 0x80
F_Bit         equ 0x40

_STACK_BASEADDRESS    EQU 0x33ff8000


;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 ~

    AREA    Init,CODE,READONLY

    ENTRY

    b   ResetHandler
    b   .      ;handler for Undefined mode
    b   .      ;handler for SWI interrupt
    b   .      ;handler for PAbort
    b   .      ;handler for DAbort
    b   .      ;reserved
    b   .      ;handler for IRQ interrupt
    b   .      ;handler for FIQ interrupt


ResetHandler

MSR CPSR_c,#Mode_User|I_Bit|F_Bit;
LDR SP,=UserStack

IMPORT  Main

   b Main       ;跳转到Main()

  END

#include "2410addr.h"

int Main(void)
{
  rGPFCON = 0x5500;
  rGPFUP  = 0xff;     // The pull up function is disabled GPF[7:0]
  rGPFDAT = 0xFF;
  rGPGCON = 0;
  rGPGUP  = 0XFF;
  while(1)
  {
  
      rGPFDAT &= ~(1<<4);   //点亮D1
    
      rGPFDAT &= ~(1<<5);   //点亮D2

      rGPFDAT &= ~(1<<6);   //点亮D3

      rGPFDAT &= ~(1<<7);   //点亮D4
  }
  

}