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调试9：定时器应用——超声波模块测距

1、超声波模块原理介绍：




2、设置定时器：
利用Applilet3来设置定时器：


得到代码：
void TAU0_Init(void)
{
 TAU0EN = 1U;  /* supplies input clock */
 
        TPS0 = _0000_TAU_CKM0_FCLK_0 | _0000_TAU_CKM1_FCLK_0 | _0000_TAU_CKM2_FCLK_1 | _0000_TAU_CKM3_FCLK_8;
 /* Stop all channels */
 
        TT0 = _0001_TAU_CH0_STOP_TRG_ON | _0002_TAU_CH1_STOP_TRG_ON | _0004_TAU_CH2_STOP_TRG_ON | _0008_TAU_CH3_STOP_TRG_ON | _0010_TAU_CH4_STOP_TRG_ON | _0020_TAU_CH5_STOP_TRG_ON | _0040_TAU_CH6_STOP_TRG_ON | _0080_TAU_CH7_STOP_TRG_ON | _0200_TAU_CH1_H8_STOP_TRG_ON | _0800_TAU_CH3_H8_STOP_TRG_ON;
 /* Mask channel 0 interrupt */
 
        TMMK00 = 1U; /* disable INTTM00 interrupt */
 
        TMIF00 = 0U; /* clear INTTM00 interrupt flag */
 
        /* Mask channel 1 interrupt */
 
        TMMK01 = 1U; /* disable INTTM01 interrupt */
 
        TMIF01 = 0U; /* clear INTTM01 interrupt flag */
 
        /* Mask channel 1 higher 8 bits interrupt */
 
        TMMK01H = 1U; /* disable INTTM01H interrupt */
 
        TMIF01H = 0U; /* clear INTTM01H interrupt flag */
 
        /* Mask channel 2 interrupt */
 
        TMMK02 = 1U; 
        /* disable INTTM02 interrupt */
 
        TMIF02 = 0U; /* clear INTTM02 interrupt flag */
 
        /* Mask channel 3 interrupt */
 
        TMMK03 = 1U; /* disable INTTM03 interrupt */
 
        TMIF03 = 0U; /* clear INTTM03 interrupt flag */
 
        /* Mask channel 3 higher 8 bits interrupt */
 
        TMMK03H = 1U; /* disable INTTM03H interrupt */
 
        TMIF03H = 0U; /* clear INTTM03H interrupt flag */
 
        /* Mask channel 4 interrupt */
 
        TMMK04 = 1U; 
        /* disable INTTM04 interrupt */
 
        TMIF04 = 0U; /* clear INTTM04 interrupt flag */
 
        /* Mask channel 5 interrupt */
 
        TMMK05 = 1U; /* disable INTTM05 interrupt */
 
        TMIF05 = 0U; /* clear INTTM05 interrupt flag */
 
        /* Mask channel 6 interrupt */
 
        TMMK06 = 1U; /* disable INTTM06 interrupt */
 
        TMIF06 = 0U; /* clear INTTM06 interrupt flag */
 
        /* Mask channel 7 interrupt */
 
        TMMK07 = 1U; /* disable INTTM07 interrupt */
 
        TMIF07 = 0U; /* clear INTTM07 interrupt flag */

       
 /* Set INTTM00 high priority */
 TMPR100 = 0U;
 TMPR000 = 0U; 
        /* Channel 0 used as interval timer */
 
        TMR00 = _0000_TAU_CLOCK_SELECT_CKM0 | _0000_TAU_CLOCK_MODE_CKS | _0000_TAU_COMBINATION_SLAVE | _0000_TAU_TRIGGER_SOFTWARE | _0000_TAU_MODE_INTERVAL_TIMER | _0001_TAU_START_INT_USED;
 TDR00 = _001F_TAU_TDR00_VALUE;
 
        TO0 &= ~_0001_TAU_CH0_OUTPUT_VALUE_1;
 
        TOE0 &= ~_0001_TAU_CH0_OUTPUT_ENABLE;
 
}
/*
**-----------------------------------------------------------------------------
**
**  Abstract:
** This function starts TAU0 channel 0 counter.
**
**  Parameters:
** None
**
**  Returns:
** None
**
**-----------------------------------------------------------------------------
*/
void TAU0_Channel0_Start(void)
{
 TMIF00 = 0U; /* clear INTTM00 interrupt flag */
 TMMK00 = 0U; /* enable INTTM00 interrupt */
 TS0 |= _0001_TAU_CH0_START_TRG_ON;
}
/*
**-----------------------------------------------------------------------------
**
**  Abstract:
** This function stops TAU0 channel 0 counter.
**
**  Parameters:
** None
**
**  Returns:
** None
**
**-----------------------------------------------------------------------------
*/
void TAU0_Channel0_Stop(void)
{
 TT0 |= _0001_TAU_CH0_STOP_TRG_ON;
 /* Mask channel 0 interrupt */
 TMMK00 = 1U; /* disable INTTM00 interrupt */
 TMIF00 = 0U; /* clear INTTM00 interrupt flag */
}

3、关键程序：

主程序中只需启动定时器：TAU0_Channel0_Start();

主循环中：
   S=change_distence();
   LCD_Accel_Value2(4,0,S);

其中：
void delay1(void)   
{ 
 uchar i;
 for(i=11;i>0;i--);
}

void Get_distance(void)
{
  unsigned long int i=162400;       //3.5m测距所需的时间
  Trig_1;           //触发
  delay1();
  Trig_0; //停止触发
 //检测输入信号
 while(!(EchoIN==1)&&i>0)
 {
   i--;
 }
 if (i>0)
  {
  tick_1us=0;
  while(EchoIN==1);
  temp1=tick_1us;
  }
 
}
unsigned int change_distence()
{ 
  unsigned long int i;
   Get_distance();
   k=temp1/58.00;
   i=(uint)(k*100);
  return i;
 }

而关键的 tick_1us
是在定时中断：
#pragma vector = INTTM00_vect
__interrupt void MD_INTTM00(void)
{
 
 /* Start user code. Do not edit comment generated here */
       TM00_flag = TRUE;
       tick_1us++;
 /* End user code. Do not edit comment generated here */
}
得到的！

4、图片：




5、视频：