msp4305529测量脉宽

这是基于库的程序
// 用 CCR1捕获，得出所测信号的频率和高电平宽度
#include <msp430.h>
#include "Header_Config.h"

unsigned char overflow = 0,Sum_High_Index = 0,Sum_Rising_Index = 0,CCR_Flag = 0;
long Wide_Rising_Old = 0,Wide_Rising_Cur = 0,Wide_Rising = 0,Wide_Rising_Sum = 0,Wide_Rising_Result = 0;
long Wide_High_Cur = 0,Wide_High = 0,Wide_High_Sum = 0,Wide_High_Result = 0;

//short delay in main
void Delay(void)
{
long i = 50000;

while(i--);
}

void main(void)
{
volatile unsigned int i;
WDTCTL = WDTPW + WDTHOLD; // Stop WDT

Board_init(); // Basic GPIO initialization

//留出测试引脚
P1SEL |= BIT0;
P1DIR |= BIT0;//测量ACLK用 10k
P2SEL |= BIT2;
P2DIR |= BIT2;//测量SMCLK用 4M
P7SEL |= BIT7;
P7DIR |= BIT7;//测量MCLK用 4M

//配置晶振为4M
P5SEL |= BIT2|BIT3; //将IO配置为XT2功能
UCSCTL6 &= ~XT2OFF; //使能XT2

UCSCTL4 = UCSCTL4&(~(SELA_7))|SELA_1; //先将ACLK配置为VLOCLK
UCSCTL3 |= SELREF_2; //将REFCLK配置为REFCLK

while (SFRIFG1 & OFIFG)
{
UCSCTL7 &= ~(XT2OFFG + XT1LFOFFG + DCOFFG); // 清除三类时钟标志位
SFRIFG1 &= ~OFIFG; // 清除时钟错误标志位
}
UCSCTL4 = UCSCTL4&(~(SELS_7|SELM_7))|SELS_5|SELM_5; //将SMCLK和MCLK时钟源配置为XT2
__enable_interrupt(); // Globally enable interrupts

//Set up LCD
Dogs102x6_init();
Dogs102x6_backlightInit();

Dogs102x6_setBacklight(11);
Dogs102x6_setContrast(11);
Dogs102x6_clearScreen();

//TA寄存器的配置
P2DIR &= ~BIT0; // P2.0
P2SEL |= BIT0; // P2.0
TA1CCTL1 = CM_3 + SCS + CCIS_0 + CAP + CCIE + ID_2; // 上升沿和下降沿都捕获
TA1CTL = TASSEL_2 + MC_2 + TAIE + TACLR; // SMCLK, contmode, interrupt
//_BIS_SR(GIE); // Enter LPM0 w/ interrupt

Dogs102x6_stringDrawXY(1, 1, "Hehe", DOGS102x6_DRAW_NORMAL);

//loop in main
while(1)
{
if(CCR_Flag)
{
CCR_Flag = 0; // 捕获结果处理
//Dogs102x6_clearScreen();
//Delay();
Dogs102x6_numDisplay(3,0,Wide_Rising_Result,0);
Dogs102x6_numDisplay(5,0,Wide_High_Result,0); // 高电平宽度
}
}
}

// Timer_A3 Interrupt Vector (TAIV) handler
#pragma vector=TIMER1_A1_VECTOR
__interrupt void TIMER1_A1_ISR(void)
{
switch(TA1IV)
{
case 2:
TA1CCTL1 &= ~CCIFG;
if((P2IN&BIT0)==BIT0) // 上升沿引发的中断
{
Wide_Rising_Cur = TA1CCR1; // 读取当前所得的最新捕获值
Wide_Rising = 65536*overflow - Wide_Rising_Old + Wide_Rising_Cur; // 防止出现溢出
Wide_Rising_Old = Wide_Rising_Cur;
overflow = 10;
Sum_Rising_Index++;
if(Sum_Rising_Index>4) // 丢掉前几次不稳定数据
{
Wide_Rising_Sum += Wide_Rising;
if(Sum_Rising_Index==12)
{
Sum_Rising_Index = 0;
Wide_Rising_Result = Wide_Rising_Sum>>3; // 得出8次捕获平均值
Wide_Rising_Sum = 0;

Wide_High_Result = Wide_High_Sum/7;// 得出7次高点平捕获平均值，服务于上升沿捕获
Wide_High_Sum = 0;

CCR_Flag = 1; // 置捕获完成标志位
}
}
}
else // 下降沿引发的中断,记录高电平宽度
{
Wide_High_Cur = TA1CCR1; // 读取当前所得的最新捕获值
Wide_High = 65536*overflow - Wide_Rising_Old + Wide_High_Cur; // 防止出现溢出，计算出高电平宽度
//overflow = 0; // 此处不清overflow，一个周期后清除
if(Sum_Rising_Index>4) // 丢掉前几次不稳定数据
{
Wide_High_Sum += Wide_High;
}
}

break;
case 4: break; // CCR2 not used
case 10: overflow++; // overflow
TA1CTL &= ~TAIFG;
break;
}
}