外部晶振不焊接ACLK时钟源仍能工作不

2万 · 2015-12-13 09:29

前不久在修理一些坏板子的时候发现，板子上的外部晶振取下来后，用ACLK作时钟源的TimeA中断事件仍然被触发，通过仿真后发现确实进入TimerA中断函数中，并且IFG1中的OFIFG位也未被置1

2万 · 2015-12-13 09:30

你把代码贴出来看看

2万 · 2015-12-13 09:30

//初始化时调用函数，初始化DCO为8MHZ

void InitClk()

{

  /*等待电压稳定*/

  DelayN(30);



  IE1 |= OFIE;                            /*Ena××e osc fault int (NMI)*/

  BCS1_Fren_Addr=(uchar*)CALBC1_8MHZ_;

  BCSCTL1 = *BCS1_Fren_Addr;

  DCO_Fren_Addr=(uchar*)CALDCO_8MHZ_;

  DCOCTL = *DCO_Fren_Addr;

}

//中断函数检测OSC 错误

#pragma vector=NMI_VECTOR

__interrupt void OscFault(void)

{

  volatile uint uiCnt;

#ifdef ALARMLED

  LedR_1;

#endif

  do                                     /* Loop until flag is clear*/

  {

IFG1 &= ~OFIFG;                      /* Clear fault flag*/

for (uiCnt = 0xFFFF; uiCnt; uiCnt--);             /* Delay for crystal to start*/

  }

  while (IFG1 & OFIFG);                   /* Test LF oscillator fault flag*/

  IE1 |= OFIE;                            /* Re-ena××e osc fault int*/

#ifdef ALARMLED

  LedR_0;

#endif

}

//TimerA初始化函数

void InitTimer()

{

  uint uiResultInteger;

  TACTL = TASSEL0 + TACLR + ID0;  /*TimerAClock=ACLK ，divided by 2，clear TAR*/

  TACTL |= MC0;

  uiResultInteger = rand();

  uiResultInteger &= 0x00ff;

  CCR0 = (uiResultInteger + uiWorkFrequence)<<3;  /*woke interval = (CCR0)*0.061ms */

  CCTL0 |= CCIE;                /*CCR0 interrupt ena××e*/

}

1万 · 2015-12-13 09:30

什么片子

2万 · 2015-12-13 09:30

芯片是是430f2121

2万 · 2015-12-13 09:31

看user's guide上说MCLK的时钟源如果选择外部XT2，XT2失效后会自动切换到DCO，那是不是ACLK也会有LFXT1切换为其他的时钟源呢？

1万 · 2015-12-13 09:31

晶振失效时,DCO接替.
TimerA3中断函数据中,

////////TimerA初始化函数

void InitTimer()

{

uint uiResultInteger;

TACTL = TASSEL0 + TACLR + ID0; /*TimerAClock=ACLK ，divided by 2，clear TAR*/

TACTL |= MC0;

uiResultInteger = rand();

uiResultInteger &= 0x00ff;

CCR0 = (uiResultInteger + uiWorkFrequence)<<3; /*woke interval = (CCR0)*0.061ms */

CCTL0 |= CCIE; /*CCR0 interrupt ena××e*/

}///////////////////////

"TACTL = TASSEL0 + TACLR + ID0; "没有将TA的时钟源选为你想要的ACLK,TACTL仍为0,实际选了TACLK.