M261芯片，如何用定时器计数不同频率的外部脉冲？

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

 * [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]    Demonstrates the timer event counter function.

 *

 * [url=home.php?mod=space&uid=17282]@CopyRight[/url] (C) 2019 Nuvoton Technology Corp. All rights reserved.

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

#include <stdio.h>

#include "NuMicro.h"





/**

 * @brief       Timer0 IRQ

 *

 * @param       None

 *

 * [url=home.php?mod=space&uid=266161]@return[/url]      None

 *

 * [url=home.php?mod=space&uid=1543424]@Details[/url]     The Timer0 default IRQ, declared in startup_M261.s.

 */

void TMR0_IRQHandler(void)

{

    printf("Count 1000 falling events! Test complete.\n");

    TIMER_ClearIntFlag(TIMER0);

}



void SYS_Init(void)

{

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

    /* Init System Clock                                                                                       */

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

    /* Enable HIRC clock */

    CLK_EnableXtalRC(CLK_PWRCTL_HIRCEN_Msk);



    /* Waiting for HIRC clock ready */

    CLK_WaitClockReady(CLK_STATUS_HIRCSTB_Msk);



    /* Switch HCLK clock source to HIRC */

    CLK_SetHCLK(CLK_CLKSEL0_HCLKSEL_HIRC, CLK_CLKDIV0_HCLK(1));



    /* Enable PLL */

    CLK->PLLCTL = CLK_PLLCTL_128MHz_HIRC;



    /* Waiting for PLL stable */

    CLK_WaitClockReady(CLK_STATUS_PLLSTB_Msk);



    /* Select HCLK clock source as PLL and HCLK source divider as 2 */

    CLK_SetHCLK(CLK_CLKSEL0_HCLKSEL_PLL, CLK_CLKDIV0_HCLK(2));



    /* Set SysTick source to HCLK/2 */

    CLK_SetSysTickClockSrc(CLK_CLKSEL0_STCLKSEL_HCLK_DIV2);



    /* Enable UART module clock */

    CLK_EnableModuleClock(UART0_MODULE);

    CLK_SetModuleClock(UART0_MODULE, CLK_CLKSEL1_UART0SEL_HIRC, CLK_CLKDIV0_UART0(1));



    /* Enable TIMER module clock */

    CLK_EnableModuleClock(TMR0_MODULE);

    CLK_SetModuleClock(TMR0_MODULE, CLK_CLKSEL1_TMR0SEL_PCLK0, 0);



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

    /* Init I/O Multi-function                                                                                 */

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

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

    SYS->GPB_MFPH = (SYS->GPB_MFPH & (~(UART0_RXD_PB12_Msk | UART0_TXD_PB13_Msk))) | UART0_RXD_PB12 | UART0_TXD_PB13;



    /* Set Timer0 event counter pin */

    SYS->GPB_MFPL &= ~TM0_PB5_Msk;

    SYS->GPB_MFPL |= TM0_PB5;

}



void UART_Init(void)

{

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

    /* Init UART                                                                                               */

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

    /* Reset UART module */

    SYS_ResetModule(UART0_RST);



    /* Configure UART and set UART Baudrate */

    UART_Open(DEBUG_PORT, 115200);

}



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

/*  MAIN function                                                                                          */

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

int main(void)

{

    volatile uint32_t i;



    /* Unlock protected registers */

    SYS_UnlockReg();



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

    SYS_Init();



    /* Init UART for printf */

    UART_Init();



    /* Lock protected registers */

    SYS_LockReg();



    printf("\n\nCPU [url=home.php?mod=space&uid=72445]@[/url] %d Hz\n", SystemCoreClock);

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

    printf("|    Timer Event Counter Input Sample Code    |\n");

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



    printf("# Timer0 Settings:\n");

    printf("    - Clock source is HCLK      \n");

    printf("    - Continuous counting mode  \n");

    printf("    - Interrupt enable          \n");

    printf("    - Event counter mode enable \n");

    printf("# Connect PB.4 pin to event counter pin TM0(PB.5) and pull PB.4 Low to generate TM0 event input source.\n\n");

    printf("Press any key to continue.\n\n");

    getchar();



    /* Configure PB.4 as GPIO output pin and pull initial pin status to High */

    PB->MODE = (PB->MODE & ~GPIO_MODE_MODE4_Msk) | (GPIO_MODE_OUTPUT << GPIO_MODE_MODE4_Pos);

    PB4 = 1;



    /* Give a dummy target frequency here. Will over write prescale and compare value with macro. */

    TIMER_Open(TIMER0, TIMER_ONESHOT_MODE, 100);

    /* Update prescale and compare value to what we need in event counter mode. */

    TIMER_SET_PRESCALE_VALUE(TIMER0, 0);

    TIMER_SET_CMP_VALUE(TIMER0, 1000);



    /* Counter increase on falling edge */

    TIMER_EnableEventCounter(TIMER0, TIMER_COUNTER_EVENT_FALLING);



    /* Enable timer interrupt */

    TIMER_EnableInt(TIMER0);

    NVIC_EnableIRQ(TMR0_IRQn);



    /* Start Timer 0 */

    TIMER_Start(TIMER0);



    for(i = 0; i < 1000; i++)

    {

        PB4 = 0;    // low

        CLK_SysTickDelay(1);

        PB4 = 1;    // high

        CLK_SysTickDelay(1);

    }



    while(1) {}

}



/*** (C) COPYRIGHT 2019 Nuvoton Technology Corp. ***/