P1.3一直在输入2.8V的脉冲,周期10MS
#include <msp430x14x.h>
#define uint unsigned int
#define uchar unsigned char
uchar BACKFLAG=0;
uint i,n,n1,n2=0;
void Delay_ms(unsigned long nValue)
{
unsigned long nCount;
int i;
unsigned long j;
nCount=2667;
for(i=nValue;i>0;i--)
{
for(j=nCount;j>0;j--);
}
return;
}
//***************************************
void Init_TimerA(void)
{
TACCTL2 = CM_1 + SCS + CCIS_0 + CAP + CCIE; // Rising edge + CCI0A (P1.3) + Capture Mode + Interrupt
TACTL = TASSEL_2+ID_3+MC_2+TACLR; // SMCLK + Continuous Mode+8分频 +清除TAR+允许定时器溢出中断
}
#pragma vector=TIMERA1_VECTOR
__interrupt void Timer_A()//以下为参考处理程序,不使用的中断源应当删除
{
switch (TAIV)//P1.3--DJ12,P1.2--DJ34,
{
case 2:
{ //捕获/比较1中断
n1++;
P3OUT=~BIT3;
break;
}
case 4:
{ //捕获/比较2中断
n2++;
P3OUT=~BIT3;
break;
}
default:break;
}
}
//**********************************************
main()
{
unsigned int i;
WDTCTL = WDTPW + WDTHOLD ;
BCSCTL1 &= ~XT2OFF; //打开XT2振荡器
do
{
IFG1&=~OFIFG; //清除振荡错误标志
for(i=0xFF;i>0;i--);
}
while((IFG1&OFIFG)!=0); //如果标志为1,则继续循环等待
BCSCTL2 |= SELM1+SELS; //MCLK为8MHz,SMCLK为8MHz, SELM1=SELM_2
P1DIR=0X03;
P1SEL|=(BIT3+BIT2); // 选择P1^3和P1^2作为外部计数脉冲的输入端
P2DIR=0XFF;
P2OUT=0X80;
P3DIR|=(BIT0+BIT1+BIT2+BIT3+BIT4);
P3OUT=~BIT0;
P4DIR=0X1F;//P4^1、P4^2、P4^3、P4^4作为PWM的输出端
P4OUT=0X00;
P5DIR=0X00;
P6DIR=0X00;
P6SEL=0XF0;
Init_TimerA();
_EINT();
while(1)
{
P2OUT=0XE0;
Delay_ms(5);
P4OUT=0X08;
}
}