请教高手一个AT91SAM7S64的问题!!!!!!

micheal001

高手帮忙看一下，我在初始化的时候设置了打开看门狗，但是为什么在程序全速运行时，
没有重新设置看门狗，但AT91SAM7S64在超时到了为什么不复位？是不是需要其他设置，
请高手帮忙！！！！

//*----------------------------------------------------------------------------
//*         ATMEL Microcontroller Software Support  -  ROUSSET  -
//*----------------------------------------------------------------------------
//* The software is delivered "AS IS" without warranty or condition of any
//* kind, either express, implied or statutory. This includes without
//* limitation any warranty or condition with respect to merchantability or
//* fitness for any particular purpose, or against the infringements of
//* intellectual property rights of others.
//*----------------------------------------------------------------------------
//* File Name           : Cstartup_SAM7.c
//* Object              : Low level initializations written in C for Tools
//* Creation            : 12/Jun/04
//* 1.2   28/Feb/05 JPP : LIB change AT91C_WDTC_WDDIS & PLL
//* 1.3   21/Mar/05 JPP : Change PLL Wait time
//* 1.4   21/Aug/05 JPP : Change MC_FMR Setting
//* 1.5   29/Aug/05 JPP : Change PLL error
//* 1.6   13/oct/05 JPP : Change comment
//*----------------------------------------------------------------------------
// Include the board file description
#include "Board.h"
// The following functions must be write in ARM mode this function called directly
// by exception vector
extern void AT91F_Spurious_handler(void);
extern void AT91F_Default_IRQ_handler(void);
extern void AT91F_Default_FIQ_handler(void);
//*----------------------------------------------------------------------------
//* \fn    AT91F_LowLevelInit
//* \brief This function performs very low level HW initialization
//*        this function can be use a Stack, depending the compilation
//*        optimization mode
//*----------------------------------------------------------------------------
void AT91F_LowLevelInit( void)
{
int            i;
AT91PS_PMC     pPMC = AT91C_BASE_PMC;
    //* Set Flash Waite sate
//  Single Cycle Access at Up to 30 MHz, or 40
     AT91C_BASE_MC->MC_FMR = AT91C_MC_FWS_1FWS ;
/*
    //Watchdog Disable
        AT91C_BASE_WDTC->WDTC_WDMR= AT91C_WDTC_WDDIS;
*/
       AT91C_BASE_WDTC->WDTC_WDMR=(1<<29)|(1<<28)|(0x800<<16)|(1<<13)|0x800;   
      
//* Set MCK at 48 054 850
    // 1 Enabling the Main Oscillator:
        // SCK = 1/32768 = 30.51 uSecond
     // Start up time = 8 * 6 / SCK = 56 * 30.51 = 1,46484375 ms
       pPMC->PMC_MOR = (( AT91C_CKGR_OSCOUNT & (0x06 <<8) | AT91C_CKGR_MOSCEN ));
        // Wait the startup time
        while(!(pPMC->PMC_SR & AT91C_PMC_MOSCS));
// 2 Checking the Main Oscillator Frequency (Optional)
// 3 Setting PLL and divider:
  // - div by 14 Fin = 1.3165 =(18,432 / 14)
  // - Mul 72+1: Fout = 96.1097 =(3,6864 *73)
  // for 96 MHz the erroe is 0.11%
  // Field out NOT USED = 0
  // PLLCOUNT pll startup time estimate at : 0.844 ms
  // PLLCOUNT 28 = 0.000844 /(1/32768)
       pPMC->PMC_PLLR = ((AT91C_CKGR_DIV & 14 ) |
                         (AT91C_CKGR_PLLCOUNT & (28<<8)) |
                         (AT91C_CKGR_MUL & (72<<16)));

        // Wait the startup time
        while(!(pPMC->PMC_SR & AT91C_PMC_LOCK));
        while(!(pPMC->PMC_SR & AT91C_PMC_MCKRDY));
  // 4. Selection of Master Clock and Processor Clock
  // select the PLL clock divided by 2
      pPMC->PMC_MCKR =  AT91C_PMC_PRES_CLK_2 ;
      while(!(pPMC->PMC_SR & AT91C_PMC_MCKRDY));
      pPMC->PMC_MCKR |= AT91C_PMC_CSS_PLL_CLK  ;
      while(!(pPMC->PMC_SR & AT91C_PMC_MCKRDY));
// Set up the default interrupts handler vectors
AT91C_BASE_AIC->AIC_SVR[0] = (int) AT91F_Default_FIQ_handler ;
for (i=1;i < 31; i++)
{
     AT91C_BASE_AIC->AIC_SVR = (int) AT91F_Default_IRQ_handler ;
}
AT91C_BASE_AIC->AIC_SPU  = (int) AT91F_Spurious_handler ;
}