/**************************************************************************//**
 * @file     main.c
 * @version  V3.00
 * $Revision: 2 $
 * $Date: 16/10/25 4:26p $
 * @brief    Show how to set GPIO pin mode and use pin data input/output control.
 * @note
 * @copyright SPDX-License-Identifier: Apache-2.0
 *
 * @copyright Copyright (C) 2016 Nuvoton Technology Corp. All rights reserved.
 ******************************************************************************/
#include "stdio.h"
#include "NUC126.h"

#define PLLCTL_SETTING      CLK_PLLCTL_72MHz_HXT
#define PLL_CLOCK           72000000


void SYS_Init(void)
{
	uint32_t u32TimeOutCnt;


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

    /* Enable HIRC clock (Internal RC 22.1184MHz) */
    CLK->PWRCTL |= CLK_PWRCTL_HIRCEN_Msk;

    /* Wait for HIRC clock ready */
    u32TimeOutCnt = __HIRC;
    while(!(CLK->STATUS & CLK_STATUS_HIRCSTB_Msk))
		if(--u32TimeOutCnt == 0) break;

    /* Select HCLK clock source as HIRC and HCLK clock divider as 1 */
    CLK->CLKSEL0 = (CLK->CLKSEL0 & (~CLK_CLKSEL0_HCLKSEL_Msk)) | CLK_CLKSEL0_HCLKSEL_HIRC;
    CLK->CLKDIV0 = (CLK->CLKDIV0 & (~CLK_CLKDIV0_HCLKDIV_Msk)) | CLK_CLKDIV0_HCLK(1);

    /* Set PLL to Power-down mode */
    CLK->PLLCTL |= CLK_PLLCTL_PD_Msk;

    /* Enable HXT clock (external XTAL 12MHz) */
    CLK->PWRCTL |= CLK_PWRCTL_HXTEN_Msk;

    /* Wait for HXT clock ready */
    u32TimeOutCnt = __HIRC;
    while(!(CLK->STATUS & CLK_STATUS_HXTSTB_Msk))
		if(--u32TimeOutCnt == 0) break;

    /* Set core clock as PLL_CLOCK from PLL */
    CLK->PLLCTL = PLLCTL_SETTING;
    u32TimeOutCnt = __HIRC;
    while(!(CLK->STATUS & CLK_STATUS_PLLSTB_Msk))
		if(--u32TimeOutCnt == 0) break;
    CLK->CLKSEL0 = (CLK->CLKSEL0 & (~CLK_CLKSEL0_HCLKSEL_Msk)) | CLK_CLKSEL0_HCLKSEL_PLL;

    /* Update System Core Clock */
    PllClock        = PLL_CLOCK;            // PLL
    SystemCoreClock = PLL_CLOCK / 1;        // HCLK
    CyclesPerUs     = PLL_CLOCK / 1000000;  // For CLK_SysTickDelay()

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

    /* Select UART module clock source as HXT and UART module clock divider as 1 */
    CLK->CLKSEL1 = (CLK->CLKSEL1 & (~CLK_CLKSEL1_UARTSEL_Msk)) | CLK_CLKSEL1_UARTSEL_HXT;
    CLK->CLKDIV0 = (CLK->CLKDIV0 & (~CLK_CLKDIV0_UARTDIV_Msk)) | CLK_CLKDIV0_UART(1);

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

    /* Set PD multi-function pins for UART0 RXD(PD.0) and TXD(PD.1) */
    SYS->GPD_MFPL = (SYS->GPD_MFPL & (~SYS_GPD_MFPL_PD0MFP_Msk)) | SYS_GPD_MFPL_PD0MFP_UART0_RXD;
    SYS->GPD_MFPL = (SYS->GPD_MFPL & (~SYS_GPD_MFPL_PD1MFP_Msk)) | SYS_GPD_MFPL_PD1MFP_UART0_TXD;

}

void UART0_Init()
{
    /*---------------------------------------------------------------------------------------------------------*/
    /* Init UART                                                                                               */
    /*---------------------------------------------------------------------------------------------------------*/
    /* Reset UART0 */
    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(__HXT, 115200);
    UART0->LINE = UART_WORD_LEN_8 | UART_PARITY_NONE | UART_STOP_BIT_1;
}

/*---------------------------------------------------------------------------------------------------------*/
/*  Main Function                                                                                          */
/*---------------------------------------------------------------------------------------------------------*/
int32_t main(void)
{

    int32_t i32Err, i32TimeOutCnt;

    /* Unlock protected registers */
    SYS_UnlockReg();

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

    /* Lock protected registers */
    SYS_LockReg();

    /* Init UART0 for printf */
    UART0_Init();

    printf("\n\nCPU @ %d Hz\n", SystemCoreClock);
    printf("+-------------------------------------------------+\n");
    printf("|    PB.2(Output) and PE.1(Input) Sample Code     |\n");
    printf("+-------------------------------------------------+\n\n");

    /*-----------------------------------------------------------------------------------------------------*/
    /* GPIO Basic Mode Test --- Use Pin Data Input/Output to control GPIO pin                              */
    /*-----------------------------------------------------------------------------------------------------*/
    printf("  >> Please connect PB.2 and PE.1 first << \n");
    printf("     Press any key to start test by using [Pin Data Input/Output Control] \n\n");
    getchar();

    /* Configure PB.2 as Output mode and PE.1 as Input mode then close it */
    PB->MODE = (PB->MODE & (~GPIO_MODE_MODE2_Msk)) | (GPIO_MODE_OUTPUT << GPIO_MODE_MODE2_Pos);
    PE->MODE = (PE->MODE & (~GPIO_MODE_MODE1_Msk)) | (GPIO_MODE_INPUT << GPIO_MODE_MODE1_Pos);

    i32Err = 0;
    printf("GPIO PB.2(output mode) connect to PE.1(input mode) ......");

    /* Use Pin Data Input/Output Control to pull specified I/O or get I/O pin status */
    /* Set PB.2 output pin value is low */
    PB2 = 0;

    /* Set time out counter */
    i32TimeOutCnt = 100;

    /* Wait for PE.1 input pin status is low for a while */
    while(PE1 != 0)
    {
        if(i32TimeOutCnt > 0)
        {
            i32TimeOutCnt--;
        }
        else
        {
            i32Err = 1;
            break;
        }
    }

    /* Set PB.2 output pin value is high */
    PB2 = 1;

    /* Set time out counter */
    i32TimeOutCnt = 100;

    /* Wait for PE.1 input pin status is high for a while */
    while(PE1 != 1)
    {
        if(i32TimeOutCnt > 0)
        {
            i32TimeOutCnt--;
        }
        else
        {
            i32Err = 1;
            break;
        }
    }

    /* Print test result */
    if(i32Err)
    {
        printf("  [FAIL].\n");
    }
    else
    {
        printf("  [OK].\n");
    }

    /* Configure PB.2 and PE.1 to default Quasi-bidirectional mode */
    PB->MODE = (PB->MODE & (~GPIO_MODE_MODE2_Msk)) | (GPIO_MODE_QUASI << GPIO_MODE_MODE2_Pos);
    PE->MODE = (PE->MODE & (~GPIO_MODE_MODE1_Msk)) | (GPIO_MODE_QUASI << GPIO_MODE_MODE1_Pos);

    while(1);

}
