/**************************************************************************//**
 * @file     main.c
 * @version  V3.00
 * $Revision: 2 $
 * $Date: 16/10/25 4:27p $
 * @brief
 *           Change duty cycle and period of output waveform by BPWM Double Buffer function(Period loading mode).
 *
 * @copyright SPDX-License-Identifier: Apache-2.0
 * @copyright Copyright (C) 2021 Nuvoton Technology Corp. All rights reserved.
 ******************************************************************************/
#include <stdio.h>
#include "NuMicro.h"

/*---------------------------------------------------------------------------------------------------------*/
/* Macro, type and constant definitions                                                                    */
/*---------------------------------------------------------------------------------------------------------*/


/*---------------------------------------------------------------------------------------------------------*/
/* Global variables                                                                                        */
/*---------------------------------------------------------------------------------------------------------*/

/**
 * @brief       BPWM0 IRQ Handler
 *
 * @param       None
 *
 * @return      None
 *
 * @details     ISR to handle BPWM0 interrupt event
 */
void BPWM0_IRQHandler(void)
{
    static int toggle = 0;

    /* Update BPWM0 channel 0 period and duty */
    if(toggle == 0)
    {
        BPWM_SET_CNR(BPWM0, 0, 99);
        BPWM_SET_CMR(BPWM0, 0, 40);
    }
    else
    {
        BPWM_SET_CNR(BPWM0, 0, 399);
        BPWM_SET_CMR(BPWM0, 0, 200);
    }
    toggle ^= 1;
    /* Clear channel 0 period interrupt flag */
    BPWM0->INTSTS = BPWM_INTSTS_PIF0_Msk;
}

void SYS_Init(void)
{

    /*---------------------------------------------------------------------------------------------------------*/
    /* Init System Clock                                                                                       */
    /*---------------------------------------------------------------------------------------------------------*/

    /* Enable HIRC clock */
    CLK->PWRCTL |= CLK_PWRCTL_HIRCEN_Msk;

    /* Wait for HIRC clock ready */
    while (!(CLK->STATUS & CLK_STATUS_HIRCSTB_Msk));

    /* Select HCLK clock source as HIRC first */
    CLK->CLKSEL0 = (CLK->CLKSEL0 & (~CLK_CLKSEL0_HCLKSEL_Msk)) | CLK_CLKSEL0_HCLKSEL_HIRC;

    /* Disable PLL clock before setting PLL frequency */
    CLK->PLLCTL |= CLK_PLLCTL_PD_Msk;

    /* Set PLL clock as 144MHz from HIRC/2 */
    CLK->PLLCTL = CLK_PLLCTL_144MHz_HIRC_DIV2;

    /* Wait for PLL clock ready */
    while (!(CLK->STATUS & CLK_STATUS_PLLSTB_Msk));

    /* Select HCLK clock source as PLL/2 and HCLK source divider as 1 */
    CLK->CLKDIV0 = (CLK->CLKDIV0 & (~CLK_CLKDIV0_HCLKDIV_Msk)) | CLK_CLKDIV0_HCLK(1);
    CLK->CLKSEL0 = (CLK->CLKSEL0 & (~CLK_CLKSEL0_HCLKSEL_Msk)) | CLK_CLKSEL0_HCLKSEL_PLL_DIV2;

    /* Update System Core Clock */
    SystemCoreClockUpdate();

    /* Enable UART0 module clock */
    CLK->APBCLK0 |= CLK_APBCLK0_UART0CKEN_Msk;

    /* Select UART0 module clock source as HIRC/2 and UART0 module clock divider as 1 */
    CLK->CLKSEL1 = (CLK->CLKSEL1 & (~CLK_CLKSEL1_UART0SEL_Msk)) | CLK_CLKSEL1_UART0SEL_HIRC_DIV2;
    CLK->CLKDIV0 = (CLK->CLKDIV0 & (~CLK_CLKDIV0_UART0DIV_Msk)) | CLK_CLKDIV0_UART0(1);

    /* Enable BPWM0 module clock */
    CLK->APBCLK0 |= CLK_APBCLK0_BPWM0CKEN_Msk;

    /*---------------------------------------------------------------------------------------------------------*/
    /* Init I/O Multi-function                                                                                 */
    /*---------------------------------------------------------------------------------------------------------*/

    /* Set PB 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 multi-function pins for BPWM */
    SYS->GPA_MFPL = (SYS->GPA_MFPL & ~(SYS_GPA_MFPL_PA0MFP_Msk | SYS_GPA_MFPL_PA1MFP_Msk | SYS_GPA_MFPL_PA2MFP_Msk | SYS_GPA_MFPL_PA3MFP_Msk)) | \
                    (SYS_GPA_MFPL_PA0MFP_BPWM0_CH0 | SYS_GPA_MFPL_PA1MFP_BPWM0_CH1 | SYS_GPA_MFPL_PA2MFP_BPWM0_CH2 | SYS_GPA_MFPL_PA3MFP_BPWM0_CH3);

}

void UART0_Init()
{
    /*---------------------------------------------------------------------------------------------------------*/
    /* Init UART                                                                                               */
    /*---------------------------------------------------------------------------------------------------------*/
    /* Reset UART IP */
    SYS->IPRST1 |=  SYS_IPRST1_UART0RST_Msk;
    SYS->IPRST1 &= ~SYS_IPRST1_UART0RST_Msk;

    /* Configure UART0 and set UART0 baud rate */
    UART0->BAUD = UART_BAUD_MODE2 | UART_BAUD_MODE2_DIVIDER(__HIRC>>1, 115200);
    UART0->LINE = UART_WORD_LEN_8 | UART_PARITY_NONE | UART_STOP_BIT_1;
}


/*---------------------------------------------------------------------------------------------------------*/
/*  Main Function                                                                                          */
/*---------------------------------------------------------------------------------------------------------*/
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 */

    /* Unlock protected registers */
    SYS_UnlockReg();

    /* Init System, IP clock and multi-function I/O */
    SYS_Init();

    /* Lock protected registers */
    SYS_LockReg();

    /* Init UART to 115200-8n1 for print message */
    UART0_Init();

    printf("\n\nCPU @ %dHz(PLL@ %dHz)\n", SystemCoreClock, PllClock);
    printf("+------------------------------------------------------------------------+\n");
    printf("|                          BPWM Driver Sample Code                       |\n");
    printf("|                                                                        |\n");
    printf("+------------------------------------------------------------------------+\n");
    printf("  This sample code will use BPWM0 channel 0 to output waveform\n");
    printf("  I/O configuration:\n");
    printf("    waveform output pin: BPWM0 channel 0(PA.0)\n");
    printf("\nUse double buffer feature.\n");

    /*
        BPWM0 channel 0 waveform of this sample shown below(up counter type):

        |<-        CNR + 1  clk     ->|  CNR + 1 = 399 + 1 CLKs
                       |<-  CMR clk ->|  CMR = 200 CLKs
                                      |<-   CNR + 1  ->|  CNR + 1 = 99 + 1 CLKs
                                               |<-CMR->|  CMR = 60 CLKs

         ______________                _______          ____
        |      200     |_____200______|   40  |____60__|     PWM waveform

    */

    /*
      Configure BPWM0 channel 0 init period and duty(up counter type).
      Period is PLL / (prescaler * (CNR + 1))
      Duty ratio = (CMR) / (CNR + 1)
      Period = 72 MHz / (2 * (199 + 1)) = 180000 Hz
      Duty ratio = (100) / (199 + 1) = 50%
    */

    /* Set BPWM to up counter type(edge aligned) */
    BPWM0->CTL1 &= ~BPWM_CTL1_CNTTYPE0_Msk;

    /* Set BPWM Timer clock prescaler */
    BPWM_SET_PRESCALER(BPWM0, 0, 0); /* Divided by 1 */

    /* Set BPWM Timer duty */
    BPWM_SET_CMR(BPWM0, 0, 200);

    /* Set BPWM Timer period */
    BPWM_SET_CNR(BPWM0, 0, 399);

    /* Set waveform generation */
    BPWM_SET_OUTPUT_LEVEL(BPWM0, BPWM_CH_0_MASK, BPWM_OUTPUT_HIGH, BPWM_OUTPUT_LOW, BPWM_OUTPUT_NOTHING, BPWM_OUTPUT_NOTHING);

    /* Enable output of BPWM0 channel 0 */
    BPWM0->POEN |= BPWM_POEN_POEN0_Msk;

    /* Enable BPWM0 channel 0 period interrupt, use channel 0 to measure time. */
    BPWM0->INTEN = (BPWM0->INTEN & ~BPWM_INTEN_PIEN0_Msk) | BPWM_INTEN_PIEN0_Msk;
    NVIC_EnableIRQ(BPWM0_IRQn);

    /* Start */
    BPWM0->CNTEN |= BPWM_CNTEN_CNTEN0_Msk;

    while(1);
}
