[求助]虽然简单，但困惑了我两天的问题，希望得到指点

只看该作者 · 2010-8-20 23:07

在ADS1.2下编译的程序，硬件是LPC2101，开始只是想测试一下Timer0,后来在主程序里加了一条while语句，程序运行的while语句就停下了，无法继续运行下去，希望各位大侠给予指点，万分感谢，程序如下：

#define LED_RUN (1<<6)
#define LED_T (1<<16)
#define LED_R (1<<17)

uint16 OverTimeCounter;
uint8 OverTimeFlag;

/****************************************************/
void __irq Timer0_IRQ(void)    //25ms
{

if(OverTimeCounter > 0)
  {
   OverTimeCounter--;
   if(OverTimeCounter == 0)
   {
      OverTimeFlag = 1;
      IO0CLR = LED_RUN;             //turn on
   }
}

T0IR = 0x01;
VICVectAddr = 0x00;
}

/******************************************************/
void Timer0Init(uint16 rate)
{
   T0TCR = 0x02;
   T0PR  = 0;
   T0PC  = 0;
   T0MCR = 0x03;             //match interrupt and TC reset
   T0MR0 = Fpclk / rate;
   T0TC  = 0;
   T0IR  = 0xffffffff;
   T0EMR = 0;

   IRQEnable();
   VICIntSelect = VICIntSelect & (~(1<<4));
   VICVectCntl2 = 0x20 | 4;
   VICVectAddr2 = (uint32)Timer0_IRQ;
   VICIntEnable = 1 << 4;

   T0TCR = 0x01;    //start
}

/****************************************************************/
int main(void)
{
   OverTimeCounter = 0;
   OverTimeFlag = 0;
   Timer0Init(40);          //25ms
   IO0DIR = LED_RUN | LED_T | LED_R;
   IO0SET = LED_RUN | LED_T | LED_R;             //turn off all led
   OverTimeCounter = 20;             //500ms
  /*  while(OverTimeFlag==0); */

   for(;;)
   {
         while(OverTimeFlag==0);
         IO0CLR = LED_R;                      //turn on
         if(OverTimeFlag)
         {
               OverTimeFlag = 0;
               IO0CLR = LED_T;             //turn on
         }
   }

   return 0;
}

运行结果是只有在Timer0中断程序里的LED_RUN灯亮了，其他两个灯都不亮，程序停止在while语句处，无论while语句放在主程序还是被注释处运行结果都一样。如果把while语句去掉，三个灯都亮了。困惑中，期待解决。。。。。。