/****************************************************************************//**
 * @file     main.c
 * @version  V1.01
 * @brief    Use the timer periodic mode to generate timer interrupt every 1 second
 *
 * SPDX-License-Identifier: Apache-2.0
 * @copyright (C) 2020 Nuvoton Technology Corp. All rights reserved.
*****************************************************************************/
#include <stdio.h>
#include "NuMicro.h"

#if defined (__GNUC__) && !defined(__ARMCC_VERSION) && defined(OS_USE_SEMIHOSTING)
    extern void initialise_monitor_handles(void);
#endif

void TMR0_IRQHandler(void)
{
    static uint32_t s_u32Sec = 1;
    printf("%u sec\n", s_u32Sec++);

    // clear timer interrupt flag
    TIMER_ClearIntFlag(TIMER0);
}

void SYS_Init(void)
{
    /* Unlock protected registers */
    SYS_UnlockReg();

    /* Enable HIRC clock (Internal RC 48MHz) */
    CLK_EnableXtalRC(CLK_PWRCTL_HIRCEN_Msk);
    /* Wait for HIRC clock ready */
    CLK_WaitClockReady(CLK_STATUS_HIRCSTB_Msk);

    /* Select HCLK clock source as HIRC and and HCLK source divider as 1 */
    CLK_SetHCLK(CLK_CLKSEL0_HCLKSEL_HIRC, CLK_CLKDIV0_HCLK(1));

    /* Set both PCLK0 and PCLK1 as HCLK */
    CLK->PCLKDIV = CLK_PCLKDIV_APB0DIV_DIV1 | CLK_PCLKDIV_APB1DIV_DIV1;

    /* Enable IP clock */
    CLK_EnableModuleClock(TMR0_MODULE);

    /* Select IP clock source */
    CLK_SetModuleClock(TMR0_MODULE, CLK_CLKSEL1_TMR0SEL_PCLK0, 0);

    /* Debug UART clock setting */
    UartDebugCLK();

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

    /*---------------------------------------------------------------------------------------------------------*/
    /* Init I/O Multi-function                                                                                 */
    /*---------------------------------------------------------------------------------------------------------*/
    UartDebugMFP();

    /* Lock protected registers */
    SYS_LockReg();
}

int main(void)
{
#if defined (__GNUC__) && !defined(__ARMCC_VERSION) && defined(OS_USE_SEMIHOSTING)
    initialise_monitor_handles();
#endif

    /* 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 Debug UART */
    UartDebugInit();

    printf("\nThis sample code use timer to generate interrupt every 1 second \n");

    // Set timer frequency to 1HZ
    if (TIMER_Open(TIMER0, TIMER_PERIODIC_MODE, 1) != 1)
    {
        printf("Set the frequency different from the user\n");
    }

    // Enable timer interrupt
    TIMER_EnableInt(TIMER0);
    NVIC_EnableIRQ(TMR0_IRQn);

    // Start Timer 0
    TIMER_Start(TIMER0);

    while (1);
}
