/**************************************************************************//**
 * @file     main.c
 * @version  V1.00
 * $Revision: 2 $
 * $Date: 15/02/13 5:08p $
 * @brief    Demonstrate the WWDT counter reload function
 *
 * @note
 * Copyright (C) 2015 Nuvoton Technology Corp. All rights reserved.
 *****************************************************************************/
#include "Mini58Series.h"
#include "stdio.h"

void WDT_IRQHandler(void)
{

    // Reload WWDT counter
    WWDT->RLDCNT  = WWDT_RELOAD_WORD;
    //clear WWDT interrupt flag
    WWDT->STATUS = WWDT_STATUS_WWDTIF_Msk;

    printf("WWDT counter reload\n");

}


void SYS_Init(void)
{
    /*---------------------------------------------------------------------------------------------------------*/
    /* Init System Clock                                                                                       */
    /*---------------------------------------------------------------------------------------------------------*/
    /* Unlock protected registers */
    while(SYS->REGLCTL != 1)
    {
        SYS->REGLCTL = 0x59;
        SYS->REGLCTL = 0x16;
        SYS->REGLCTL = 0x88;
    }

    /* Enable HIRC, and LIRC (for WDT) */
    CLK->PWRCTL = CLK_PWRCTL_HIRCEN_Msk | CLK_PWRCTL_LIRCEN_Msk;

    /* Waiting for clock ready */
    while((CLK->STATUS & (CLK_STATUS_HIRCSTB_Msk | CLK_STATUS_LIRCSTB_Msk)) !=
            (CLK_STATUS_HIRCSTB_Msk | CLK_STATUS_LIRCSTB_Msk));

    /* Enable UART and WDT clock */
    CLK->APBCLK = CLK_APBCLK_UART0CKEN_Msk | CLK_APBCLK_WDTCKEN_Msk;

    /* Update System Core Clock */
    /* User can use SystemCoreClockUpdate() to calculate SystemCoreClock. */
    SystemCoreClockUpdate();


    /*---------------------------------------------------------------------------------------------------------*/
    /* Init I/O Multi-function                                                                                 */
    /*---------------------------------------------------------------------------------------------------------*/
    /* Set P1 multi-function pins for UART RXD, TXD */
    SYS->P1_MFP = SYS_MFP_P12_UART0_RXD | SYS_MFP_P13_UART0_TXD;

    /* Lock protected registers */
    SYS->REGLCTL = 0;
}

void UART_Init(void)
{
    // Set UART to 8 bit character length, 1 stop bit, and no parity
    UART0->LINE = UART_LINE_WLS_Msk;
    // 22.1184 MHz reference clock input, for 115200 bps
    // 22118400 / 115200 = 192. Using mode 2 to calculate baudrate, 192 - 2 = 190 = 0xBE
    UART0->BAUD = UART_BAUD_BAUDM1_Msk | UART_BAUD_BAUDM0_Msk | (0xBE);
}

int32_t main (void)
{
    /* Init System, IP clock and multi-function I/O
       In the end of SYS_Init() will issue SYS_LockReg()
       to lock protected register. If user want to write
       protected register, please issue SYS_UnlockReg()
       to unlock protected register if necessary */
    SYS_Init();

    /* Init UART to 115200-8n1 for print message */
    UART_Init();

    printf("\nThis sample code demonstrate WWDT reload function\n");

    // WWDT register is locked, so it is necessary to unlock protect register before configure WDT
    while(SYS->REGLCTL != 1)
    {
        SYS->REGLCTL = 0x59;
        SYS->REGLCTL = 0x16;
        SYS->REGLCTL = 0x88;
    }

    // WWDT timeout every 768 * 64 WWDT clock, compare interrupt trigger at 768 * 32 WWDT clock, enable WWDT counter compare interrupt
    WWDT->CTL = WWDT_PRESCALER_768 |
                (0x20 << WWDT_CTL_CMPDAT_Pos)|
                WWDT_CTL_WWDTEN_Msk | WWDT_CTL_INTEN_Msk;

    // Enable WWDT timeout interrupt, share with WDT interrupt
    NVIC_EnableIRQ(WDT_IRQn);

    while(1);

}

/*** (C) COPYRIGHT 2015 Nuvoton Technology Corp. ***/


