【库函数】MSP430F5529 测量方波的频率及占空比

测量方波的频率及占空比"/>

【库函数】MSP430F5529 测量方波的频率及占空比

【下面的代码仅给出了实现本功能必要的部分】
其中的OLED函数部分为OLED自带的库函数
本单片机上的SMCLK 设置为了 24MHz

#define TIMER_PERIOD 2400
#define DUTY_CYCLE 1200

//while(1) 前的初始化void Frequence_Duty_init()
{GPIO_setAsPeripheralModuleFunctionInputPin(GPIO_PORT_P1,GPIO_PIN2);//选用P1.2   使用TA0.1 Timer Capture Timer_A_initContinuousModeParam Counter = {0};Counter.clockSource = TIMER_A_CLOCKSOURCE_SMCLK;Counter.clockSourceDivider = TIMER_A_CLOCKSOURCE_DIVIDER_1;Counter.startTimer = true;Counter.timerClear = TIMER_A_DO_CLEAR;Counter.timerInterruptEnable_TAIE = TIMER_A_TAIE_INTERRUPT_DISABLE;Timer_A_initContinuousMode(TIMER_A0_BASE, &Counter);//开启一个连续模式的计时Timer_A_initCaptureModeParam CaptureParam = {0};CaptureParam.captureRegister = TIMER_A_CAPTURECOMPARE_REGISTER_1;CaptureParam.captureMode = TIMER_A_CAPTUREMODE_RISING_EDGE;CaptureParam.captureInputSelect = TIMER_A_CAPTURE_INPUTSELECT_CCIxA;CaptureParam.synchronizeCaptureSource = TIMER_A_CAPTURE_SYNCHRONOUS;CaptureParam.captureInterruptEnable = TIMER_A_CAPTURECOMPARE_INTERRUPT_ENABLE;CaptureParam.captureOutputMode = TIMER_A_OUTPUTMODE_TOGGLE;Timer_A_initCaptureMode(TIMER_A0_BASE,&CaptureParam);//开启捕获模式，并开启它的中断
}

//将此函数放到 while(1) 里面
void Frequence_Duty_Display()
{if(FreqFlag == 0){if(D2 > D1){HighClockSteps=(HighOverFlow-1) * 65536 + D2 - D1;}else{HighClockSteps=(HighOverFlow-1) * 65536 + D2 + 65536 - D1;}if(D3 > D1){AllClockSteps=(AllOverFlow-1)*65536 + D3 - D1;}else{AllClockSteps=(AllOverFlow-1)*65536 + D3 + 65536 - D1;}//占空比Duty = HighClockSteps*100.0/AllClockSteps;Point1 = Duty - (int)Duty;OLED_ShowNum(0,2,Duty,3,16);OLED_ShowString(25,2,".");OLED_ShowNum(30,2,Point1*100,2,16);//频率Frequency = 24000000.0/AllClockSteps;	//根据自己的单片机主频修改Point2 = Frequency - (int)Frequency;OLED_ShowNum(0,6,Frequency,5,16);OLED_ShowString(40,6,".");OLED_ShowNum(45,6,Point2*100,2,16);}
}

//此代码块加在 main.c 末尾
#pragma vector=TIMER0_A1_VECTOR
__interrupt void TIMER0_A1_ISR(void)
{
    Timer_A_disableCaptureCompareInterrupt (TIMER_A0_BASE,TIMER_A_CAPTURECOMPARE_REGISTER_1);if(FreqFlag == 1){static u8 index;if(TA0CCTL1&CM0&&(index==0)){TA0CCTL1|=CM_2;//更变为下降沿触发D1=TA0R;//记录初始时间D2=D3=0;HighOverFlow = AllOverFlow = 0;index=(index+1)%3;}else if((TA0CCTL1&CM1)&&(index==1))//下降沿{TA0CCTL1|=CM_1;//更改设置为上升沿触发D2 = TA0R; //记录高电平结束时间HighOverFlow = AllOverFlow;index=(index+1)%3;}else if((TA0CCTL1&CM0)&&(index==2)) //第二次上升沿{//测完一个周期，等待下一个上升沿D3 = TA0R;FreqFlag = 0;index=(index+1)%3;}}AllOverFlow++;Timer_A_clearCaptureCompareInterrupt(TIMER_A0_BASE,TIMER_A_CAPTURECOMPARE_REGISTER_1);
}

实测效果图