kl46 中断嵌套/中断优先级【已解决】

x316639495 · 发表于 2015-6-3 00:11:34

本帖最后由 x316639495 于 2016-10-10 15:21 编辑

在用kl46做项目，需要精确测量一脉冲高电平时间，脉冲触发外部中断后用PIT1来计时实现。为了精确测量，需要把外部中断的优先级设为最高，形成中断嵌套。参考了官方的例程修改优先级

void set_irq_priority (int irq, int prio)
{
/*irq priority pointer*/
uint8 *prio_reg;
uint8 err = 0;
uint8 div = 0;

/* Make sure that the IRQ is an allowable number. Right now up to 32 is
   * used.
   *
   * NOTE: If you are using the interrupt definitions from the header
   * file, you MUST SUBTRACT 16!!!
   */
if (irq > 32)
{
      printf("\nERR! Invalid IRQ value passed to priority irq function!\n");
      err = 1;
}
if (prio > 3)
{
      printf("\nERR! Invalid priority value passed to priority irq function!\n");
      err = 1;
}

if (err != 1)
{
      /* Determine which of the NVICIPx corresponds to the irq */
      div = irq / 4;
      prio_reg = (uint8 *)((uint32)&NVIC_IP(div));
      /* Assign priority to IRQ */
      *prio_reg = ( (prio&0x3) << (8 - ARM_INTERRUPT_LEVEL_BITS) );
}
}

我现在把PORTD的中断优先级设为最高。但现在PORTD中断还是无法中断其它的中断形成中断嵌套，也无法精确测量脉冲高电平的时间。其它中断源还有PIT0,UART0,TPM。请问该如何处理。谢谢
if(PORTC_ISFR & (1<<8))
  {
PORTC_ISFR |=(1<<8);
if(gpio_get(PORTC,9) )
{
   if(gpio_get(PORTC,8) )
   {

      PIT_TCTRL1 =  !PIT_TCTRL_TEN_MASK | !PIT_TCTRL_TIE_MASK | !PIT_TCTRL_CHN_MASK; //关闭定时器
      PIT_LDVAL1 =  0xFFFFFFFF;// 最大值
      PIT_TFLG1  =  PIT_TFLG_TIF_MASK; // 清除标志
      PIT_TCTRL1 |= PIT_TCTRL_TIE_MASK | PIT_TCTRL_TEN_MASK;

   }
   else
   {
      time = (0xFFFFFFFF - PIT_CVAL1)/(Bus_Fre/1000);//Bus_Fre总线时钟，计算时间，单位是微秒
      PIT_TCTRL1 =  !PIT_TCTRL_TEN_MASK | !PIT_TCTRL_TIE_MASK | !PIT_TCTRL_CHN_MASK; //关闭定时器
   }
}

我知道答案目前已有16人回答

阅读全文