ECAP抓取信号频率的方法

/**************************************************************************//**

 * [url=home.php?mod=space&uid=288409]@file[/url]     main.c

 * [url=home.php?mod=space&uid=895143]@version[/url]  V3.00

 * [url=home.php?mod=space&uid=247401]@brief[/url]    Show how to use ECAP interface to get input frequency

 *

 * [url=home.php?mod=space&uid=17282]@CopyRight[/url] (C) 2016 Nuvoton Technology Corp. All rights reserved.

 *

 ******************************************************************************/

#include <stdio.h>

#include "NuMicro.h"



#define PLL_CLOCK       192000000





/*---------------------------------------------------------------------------------------------------------*/

/* Global variables                                                                                        */

/*---------------------------------------------------------------------------------------------------------*/

uint32_t u32Status;

uint32_t u32IC0Hold;



void TMR0_IRQHandler(void)

{

    if(TIMER_GetIntFlag(TIMER0) == 1)

    {

        /* Clear Timer0 time-out interrupt flag */

        TIMER_ClearIntFlag(TIMER0);



        /*PA.0 gpio toggle */

        PA0 ^= 1;

    }

}

/*---------------------------------------------------------------------------------------------------------*/

/*  ECAP0 IRQ Handler                                                                                      */

/*---------------------------------------------------------------------------------------------------------*/

void ECAP0_IRQHandler(void)

{

    /* Get input Capture status */

    u32Status = ECAP_GET_INT_STATUS(ECAP0);



    /* Check input capture channel 0 flag */

    if((u32Status & ECAP_STATUS_CAPTF0_Msk) == ECAP_STATUS_CAPTF0_Msk)

    {

        /* Clear input capture channel 0 flag */

        ECAP_CLR_CAPTURE_FLAG(ECAP0, ECAP_STATUS_CAPTF0_Msk);



        /* Get input capture counter hold value */

        u32IC0Hold = ECAP0->HLD0;

    }



    /* Check input capture channel 1 flag */

    if((u32Status & ECAP_STATUS_CAPTF1_Msk) == ECAP_STATUS_CAPTF1_Msk)

    {

        /* Clear input capture channel 1 flag */

        ECAP_CLR_CAPTURE_FLAG(ECAP0, ECAP_STATUS_CAPTF1_Msk);

    }



    /* Check input capture channel 2 flag */

    if((u32Status & ECAP_STATUS_CAPTF2_Msk) == ECAP_STATUS_CAPTF2_Msk)

    {

        /* Clear input capture channel 2 flag */

        ECAP_CLR_CAPTURE_FLAG(ECAP0, ECAP_STATUS_CAPTF2_Msk);

    }



    /* Check input capture compare-match flag */

    if((u32Status & ECAP_STATUS_CAPCMPF_Msk) == ECAP_STATUS_CAPCMPF_Msk)

    {

        /* Clear input capture compare-match flag */

        ECAP_CLR_CAPTURE_FLAG(ECAP0,ECAP_STATUS_CAPCMPF_Msk);

    }



    /* Check input capture overflow flag */

    if((u32Status & ECAP_STATUS_CAPOVF_Msk) == ECAP_STATUS_CAPOVF_Msk)

    {

        /* Clear input capture overflow flag */

        ECAP_CLR_CAPTURE_FLAG(ECAP0,ECAP_STATUS_CAPOVF_Msk);

    }

}





void SYS_Init(void)

{

    /* Set XT1_OUT(PF.2) and XT1_IN(PF.3) to input mode */

    PF->MODE &= ~(GPIO_MODE_MODE2_Msk | GPIO_MODE_MODE3_Msk);



    /* Enable external XTAL 12MHz clock */

    CLK_EnableXtalRC(CLK_PWRCTL_HXTEN_Msk);



    /* Waiting for external XTAL clock ready */

    CLK_WaitClockReady(CLK_STATUS_HXTSTB_Msk);



    CLK_SetHCLK(CLK_CLKSEL0_HCLKSEL_HXT, CLK_CLKDIV0_HCLK(1));



    /* Set core clock as PLL_CLOCK from PLL */

    CLK_SetCoreClock(PLL_CLOCK);



    /* Set PCLK0/PCLK1 to HCLK/2 */

    CLK->PCLKDIV = (CLK_PCLKDIV_APB0DIV_DIV2 | CLK_PCLKDIV_APB1DIV_DIV2);



    /* Enable UART module clock */

    CLK_EnableModuleClock(UART0_MODULE);



    /* Enable ECAP0 module clock */

    CLK_EnableModuleClock(ECAP0_MODULE);



    /* Enable TIMER0 module clock */

    CLK_EnableModuleClock(TMR0_MODULE);



    /* Select UART module clock source */

    CLK_SetModuleClock(UART0_MODULE, CLK_CLKSEL1_UART0SEL_HXT, CLK_CLKDIV0_UART0(1));



    /* Select TIMER0 module clock source */

    CLK_SetModuleClock(TMR0_MODULE, CLK_CLKSEL1_TMR0SEL_HXT, 0);



    /* Set GPB multi-function pins for UART0 RXD and TXD */

    SYS->GPB_MFPH &= ~(SYS_GPB_MFPH_PB12MFP_Msk | SYS_GPB_MFPH_PB13MFP_Msk);

    SYS->GPB_MFPH |= (SYS_GPB_MFPH_PB12MFP_UART0_RXD | SYS_GPB_MFPH_PB13MFP_UART0_TXD);



    /* Set PA.10 for ECAP0_IC0*/

    SYS->GPA_MFPH = (SYS->GPA_MFPH & ~SYS_GPA_MFPH_PA10MFP_Msk) |SYS_GPA_MFPH_PA10MFP_ECAP0_IC0;



}



void UART0_Init(void)

{

    /* Configure UART0 and set UART0 Baudrate */

    UART_Open(UART0, 115200);

}



void ECAP0_Init(void)

{

    /* Enable ECAP0*/

    ECAP_Open(ECAP0, ECAP_DISABLE_COMPARE);



    /* Select Reload function */

    ECAP_SET_CNT_CLEAR_EVENT(ECAP0, (ECAP_CTL1_CAP0RLDEN_Msk|ECAP_CTL1_CAP1RLDEN_Msk));



    /* Enable ECAP0 Input Channel 0*/

    ECAP_ENABLE_INPUT_CHANNEL(ECAP0, ECAP_CTL0_IC0EN_Msk);



    /* Enable ECAP0 source from IC0 */

    ECAP_SEL_INPUT_SRC(ECAP0, ECAP_IC0, ECAP_CAP_INPUT_SRC_FROM_IC);



    /* Select IC0 detect rising edge */

    ECAP_SEL_CAPTURE_EDGE(ECAP0, ECAP_IC0, ECAP_RISING_EDGE);



    /* Input Channel 0 interrupt enabled */

    ECAP_EnableINT(ECAP0, ECAP_CTL0_CAPIEN0_Msk);

}



void Timer0_Init(void)

{



    /* Open Timer0 in periodic mode, enable interrupt and 1 interrupt tick per second */

    TIMER_Open(TIMER0,TIMER_PERIODIC_MODE,10000);

    TIMER_EnableInt(TIMER0);



    /* Enable Timer0 NVIC */

    NVIC_EnableIRQ(TMR0_IRQn);



}





int32_t main(void)

{

    uint32_t u32Hz=0, u32Hz_DET=0;



    /* Unlock protected registers */

    SYS_UnlockReg();



    /* Init System, IP clock and multi-function I/O */

    SYS_Init();



    /* Lock protected registers */

    SYS_LockReg();



    /* Init UART0 for printf */

    UART0_Init();



    printf("\n");

    printf("+----------------------------------------------------------+\n");

    printf("|   M480 Enhanced Input Capture Timer Driver Sample Code   |\n");

    printf("+----------------------------------------------------------+\n");

    printf("\n");

    printf("  !! GPIO PA.0 toggle periodically    !!\n");

    printf("  !! Connect PA.0 --> PA.10(ECAP0_IC0) !!\n\n");

    printf("     Press any key to start test\n\n");

    getchar();



    /* Initial ECAP0 function */

    ECAP0_Init();



    /* Initial Timer0 function */

    Timer0_Init();



    /* Configure PA.0 as output mode */

    GPIO_SetMode(PA, BIT0, GPIO_MODE_OUTPUT);



    /* Start Timer0 counting */

    TIMER_Start(TIMER0);



    /* Delay 200ms */

    CLK_SysTickDelay(200000);



    /* Init & clear ECAP interrupt status flags */

    u32Status = ECAP_GET_INT_STATUS(ECAP0);

    ECAP0->STATUS = u32Status;



    /* ECAP_CNT starts up-counting */

    ECAP_CNT_START(ECAP0);



    while(1)

    {

        if(u32Status != 0)

        {

            /* Input Capture status is changed, and get a new hold value of input capture counter */

            u32Status = 0;



            /* Calculate the IC0 input frequency */

            u32Hz_DET = (SystemCoreClock/2) / (u32IC0Hold + 1);





            if(u32Hz != u32Hz_DET)

            {

                /* If IC0 input frequency is changed, Update frequency */

                u32Hz = u32Hz_DET;

            }

            else

            {

                printf("\nECAP0_IC0 input frequency is %d (Hz),u32IC0Hold=0x%08x\n", u32Hz,u32IC0Hold);

                TIMER_Stop(TIMER0); //Disable timer Counting.

                break;

            }

        }



    }

    /* Disable External Interrupt */

    NVIC_DisableIRQ(ECAP0_IRQn);

    NVIC_DisableIRQ(TMR0_IRQn);



    /* Disable ECAP function */

    ECAP_Close(ECAP0);



    /* Disable Timer0 IP clock */

    CLK_DisableModuleClock(TMR0_MODULE);



    /* Disable ECAP IP clock */

    CLK_DisableModuleClock(ECAP0_MODULE);



    printf("\nExit ECAP sample code\n");



    while(1);

}