周期性的看门狗定时器（WDT）超时中断

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

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

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

 * $Revision: 4 $

 * $Date: 15/09/14 4:05p $

 * [url=home.php?mod=space&uid=247401]@brief[/url]    Implement periodic WDT time-out interrupt event.

 * @note

 * Copyright (C) 2013 Nuvoton Technology Corp. All rights reserved.

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

#include <stdio.h>

#include "M058S.h"



#define PLL_CLOCK           50000000





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

/* Global Interface Variables Declarations                                                                 */

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

volatile uint8_t g_u8IsWDTTimeoutINT = 0;





/**

 * @brief       IRQ Handler for WDT and WWDT Interrupt

 *

 * @param       None

 *

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

 *

 * [url=home.php?mod=space&uid=1543424]@Details[/url]     The WDT_IRQHandler is default IRQ of WDT and WWDT, declared in startup_M058S.s.

 */

void WDT_IRQHandler(void)

{

    if(WDT_GET_TIMEOUT_INT_FLAG() == 1)

    {

        /* Clear WDT time-out interrupt flag */

        WDT_CLEAR_TIMEOUT_INT_FLAG();



        g_u8IsWDTTimeoutINT = 1;

    }

}



void SYS_Init(void)

{

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

    /* Init System Clock                                                                                       */

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

    /* Enable HIRC 22.1184MHz clock */

    CLK_EnableXtalRC(CLK_PWRCON_OSC22M_EN_Msk);



    /* Waiting for HIRC clock ready */

    CLK_WaitClockReady(CLK_CLKSTATUS_OSC22M_STB_Msk);



    /* Switch HCLK clock source to HIRC and HCLK source divide 1 */

    CLK_SetHCLK(CLK_CLKSEL0_HCLK_S_HIRC, CLK_CLKDIV_HCLK(1));



    /* Enable external XTAL 12MHz and LIRC 10KHz clock */

    CLK_EnableXtalRC(CLK_PWRCON_XTL12M_EN_Msk | CLK_PWRCON_OSC10K_EN_Msk);



    /* Waiting for external XTAL and LIRC clock ready */

    CLK_WaitClockReady(CLK_CLKSTATUS_XTL12M_STB_Msk | CLK_CLKSTATUS_OSC10K_STB_Msk);



    /* Set core clock as PLL_CLOCK from PLL */

    CLK_SetCoreClock(PLL_CLOCK);



    /* Enable peripheral clock */

    CLK_EnableModuleClock(UART0_MODULE);

    CLK_EnableModuleClock(WDT_MODULE);



    /* Peripheral clock source */

    CLK_SetModuleClock(UART0_MODULE, CLK_CLKSEL1_UART_S_PLL, CLK_CLKDIV_UART(1));

    CLK_SetModuleClock(WDT_MODULE, CLK_CLKSEL1_WDT_S_LIRC, 0);



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

    /* Init I/O Multi-function                                                                                 */

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

    /* Set P3 multi-function pins for UART0 RXD, TXD */

    SYS->P3_MFP &= ~(SYS_MFP_P30_Msk | SYS_MFP_P31_Msk);

    SYS->P3_MFP |= (SYS_MFP_P30_RXD | SYS_MFP_P31_TXD);

}



void UART0_Init(void)

{

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

    /* Init UART                                                                                               */

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

    /* Reset IP */

    SYS_ResetModule(UART0_RST);



    /* Configure UART0 and set UART0 Baudrate */

    UART_Open(UART0, 115200);

}



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

/*  MAIN function                                                                                          */

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

int main(void)

{

    uint32_t u32IntCnts = 0;



    /* Unlock protected registers */

    SYS_UnlockReg();



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

    SYS_Init();



    /* Init UART0 for printf */

    UART0_Init();



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

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

    printf("|    WDT Time-out Period Sample Code    |\n");

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



    printf("# WDT Settings:\n");

    printf("  Clock source is 10 kHz; Enable interrupt; Time-out interval is 2^14 * WDT clock.\n");

    printf("# When WDT statr counting, system will generate a WDT time-out interrupt after 1.6384 ~ 1.7408 s.\n");

    printf("  Measure P0.0 period time to check time-out interval.\n\n");



    /* Use P0.0 to check time-out period time */

    GPIO_SetMode(P0, BIT0, GPIO_PMD_OUTPUT);

    P00 = 1;

    P00 = 0;



    /* Because of all bits can be written in WDT Control Register are write-protected;

       To program it needs to disable register protection first. */

    SYS_UnlockReg();



    /* Select WDT time-out interval to 2^14 * WDT clock then start WDT counting */

    g_u8IsWDTTimeoutINT = 0;

    WDT_Open(WDT_TIMEOUT_2POW14, 0, FALSE, FALSE);



    /* Enable WDT interrupt function */

    WDT_EnableInt();



    /* Enable WDT NVIC */

    NVIC_EnableIRQ(WDT_IRQn);



    while(1)

    {

        /* Check if WDT time-out interrupt occurred or not */

        while(g_u8IsWDTTimeoutINT == 0);



        g_u8IsWDTTimeoutINT = 0;

        P00 ^= 1;



        printf("WDT time-out interrupt occurred. INT counts: %d      \r", ++u32IntCnts);

    }

}



/*** (C) COPYRIGHT 2013 Nuvoton Technology Corp. ***/