/**************************************************************************//**
 * @file     main.c
 * @version  V2.00
 * @brief    Read/write EEPROM via I2C interface
 *
 * @copyright SPDX-License-Identifier: Apache-2.0
 * @copyright Copyright (C) 2021 Nuvoton Technology Corp. All rights reserved.
 ******************************************************************************/
#include <stdio.h>
#include "NuMicro.h"

/*---------------------------------------------------------------------------------------------------------*/
/* Global variables                                                                                        */
/*---------------------------------------------------------------------------------------------------------*/
uint8_t g_u8DeviceAddr;
uint8_t g_au8TxData[3];
uint8_t g_u8RxData;
volatile uint8_t g_u8DataLen;
volatile uint8_t g_u8EndFlag = 0;

typedef void (*I2C_FUNC)(uint32_t u32Status);

static I2C_FUNC s_I2C0HandlerFn = NULL;

/*---------------------------------------------------------------------------------------------------------*/
/*  I2C0 IRQ Handler                                                                                       */
/*---------------------------------------------------------------------------------------------------------*/
void I2C0_IRQHandler(void)
{
    uint32_t u32Status;

    u32Status = I2C_GET_STATUS(I2C0);

    if(I2C_GET_TIMEOUT_FLAG(I2C0))
    {
        /* Clear I2C0 Timeout Flag */
        I2C_ClearTimeoutFlag(I2C0);
    }
    else
    {
        if(s_I2C0HandlerFn != NULL)
            s_I2C0HandlerFn(u32Status);
    }
}

/*---------------------------------------------------------------------------------------------------------*/
/*  I2C Rx Callback Function                                                                               */
/*---------------------------------------------------------------------------------------------------------*/
void I2C_MasterRx(uint32_t u32Status)
{
    if(u32Status == 0x08)                       /* START has been transmitted and prepare SLA+W */
    {
        I2C_SET_DATA(I2C0, (g_u8DeviceAddr << 1)); /* Write SLA+W to Register I2CDAT */
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI);
    }
    else if(u32Status == 0x18)                  /* SLA+W has been transmitted and ACK has been received */
    {
        I2C_SET_DATA(I2C0, g_au8TxData[g_u8DataLen++]);
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI);
    }
    else if(u32Status == 0x20)                  /* SLA+W has been transmitted and NACK has been received */
    {
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_STO | I2C_CTL_SI);
    }
    else if(u32Status == 0x28)                  /* DATA has been transmitted and ACK has been received */
    {
        if(g_u8DataLen < 2)
        {
            I2C_SET_DATA(I2C0, g_au8TxData[g_u8DataLen++]);
            I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI);
        }
        else
        {
            I2C_SET_CONTROL_REG(I2C0, I2C_CTL_STA | I2C_CTL_SI);
        }
    }
    else if(u32Status == 0x10)                  /* Repeat START has been transmitted and prepare SLA+R */
    {
        I2C_SET_DATA(I2C0, (g_u8DeviceAddr << 1) | 0x01);  /* Write SLA+R to Register I2CDAT */
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI);
    }
    else if(u32Status == 0x40)                  /* SLA+R has been transmitted and ACK has been received */
    {
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI);
    }
    else if(u32Status == 0x58)                  /* DATA has been received and NACK has been returned */
    {
        g_u8RxData = I2C_GET_DATA(I2C0);
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_STO | I2C_CTL_SI);
        g_u8EndFlag = 1;
    }
    else
    {
        /* TO DO */
        printf("Status 0x%x is NOT processed\n", u32Status);
    }
}

/*---------------------------------------------------------------------------------------------------------*/
/*  I2C Tx Callback Function                                                                               */
/*---------------------------------------------------------------------------------------------------------*/
void I2C_MasterTx(uint32_t u32Status)
{
    if(u32Status == 0x08)                       /* START has been transmitted */
    {
        I2C_SET_DATA(I2C0, g_u8DeviceAddr << 1);  /* Write SLA+W to Register I2CDAT */
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI);
    }
    else if(u32Status == 0x18)                  /* SLA+W has been transmitted and ACK has been received */
    {
        I2C_SET_DATA(I2C0, g_au8TxData[g_u8DataLen++]);
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI);
    }
    else if(u32Status == 0x20)                  /* SLA+W has been transmitted and NACK has been received */
    {
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_STA | I2C_CTL_STO | I2C_CTL_SI);
    }
    else if(u32Status == 0x28)                  /* DATA has been transmitted and ACK has been received */
    {
        if(g_u8DataLen != 3)
        {
            I2C_SET_DATA(I2C0, g_au8TxData[g_u8DataLen++]);
            I2C_SET_CONTROL_REG(I2C0, I2C_CTL_SI);
        }
        else
        {
            I2C_SET_CONTROL_REG(I2C0, I2C_CTL_STO | I2C_CTL_SI);
            g_u8EndFlag = 1;
        }
    }
    else
    {
        /* TO DO */
        printf("Status 0x%x is NOT processed\n", u32Status);
    }
}

void SYS_Init(void)
{
    /*---------------------------------------------------------------------------------------------------------*/
    /* Init System Clock                                                                                       */
    /*---------------------------------------------------------------------------------------------------------*/

    /* Set PCLK0 and PCLK1 to HCLK/2 */
    CLK->PCLKDIV = (CLK_PCLKDIV_APB0DIV_DIV2 | CLK_PCLKDIV_APB1DIV_DIV2);

    /* Set core clock to 200MHz */
    CLK_SetCoreClock(200000000);

    /* Enable all GPIO clock */
    CLK->AHBCLK0 |= CLK_AHBCLK0_GPACKEN_Msk | CLK_AHBCLK0_GPBCKEN_Msk | CLK_AHBCLK0_GPCCKEN_Msk | CLK_AHBCLK0_GPDCKEN_Msk |
                    CLK_AHBCLK0_GPECKEN_Msk | CLK_AHBCLK0_GPFCKEN_Msk | CLK_AHBCLK0_GPGCKEN_Msk | CLK_AHBCLK0_GPHCKEN_Msk;
    CLK->AHBCLK1 |= CLK_AHBCLK1_GPICKEN_Msk | CLK_AHBCLK1_GPJCKEN_Msk;

    /* Enable UART0 module clock */
    CLK_EnableModuleClock(UART0_MODULE);

    /* Select UART0 module clock source as HIRC and UART0 module clock divider as 1 */
    CLK_SetModuleClock(UART0_MODULE, CLK_CLKSEL1_UART0SEL_HIRC, CLK_CLKDIV0_UART0(1));

    /* Enable I2C0 clock */
    CLK_EnableModuleClock(I2C0_MODULE);

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

    /* Set multi-function pins for UART0 RXD and TXD */
    SET_UART0_RXD_PB12();
    SET_UART0_TXD_PB13();

    /* Set I2C0 multi-function pins */
    SET_I2C0_SDA_PA4();
    SET_I2C0_SCL_PA5();

    /* I2C pin enable schmitt trigger */
    PA->SMTEN |= GPIO_SMTEN_SMTEN4_Msk | GPIO_SMTEN_SMTEN5_Msk;
}

void I2C0_Init(void)
{
    /* Open I2C0 and set clock to 100k */
    I2C_Open(I2C0, 100000);

    /* Get I2C0 Bus Clock */
    printf("I2C clock %d Hz\n", I2C_GetBusClockFreq(I2C0));

    I2C_EnableInt(I2C0);
    NVIC_EnableIRQ(I2C0_IRQn);
}


int main(void)
{
    uint32_t i;
    uint32_t u32TimeOutCnt;

    /* Unlock protected registers */
    SYS_UnlockReg();

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

    /* Init UART to 115200-8n1 for print message */
    UART_Open(UART0, 115200);

    /*
        This sample code sets I2C bus clock to 100kHz. Then, accesses EEPROM 24LC64 with Byte Write
        and Byte Read operations, and check if the read data is equal to the programmed data.
    */

    printf("+-------------------------------------------------------+\n");
    printf("|          I2C Driver Sample Code with EEPROM 24LC64    |\n");
    printf("+-------------------------------------------------------+\n");

    /* Init I2C0 to access EEPROM */
    I2C0_Init();

    g_u8DeviceAddr = 0x50;

    for(i = 0; i < 2; i++)
    {
        g_au8TxData[0] = (uint8_t)((i & 0xFF00) >> 8);
        g_au8TxData[1] = (uint8_t)(i & 0x00FF);
        g_au8TxData[2] = (uint8_t)(g_au8TxData[1] + 3);

        g_u8DataLen = 0;
        g_u8EndFlag = 0;

        /* I2C function to write data to slave */
        s_I2C0HandlerFn = (I2C_FUNC)I2C_MasterTx;

        /* I2C as master sends START signal */
        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_STA);

        /* Wait I2C Tx Finish */
        u32TimeOutCnt = I2C_TIMEOUT;
        while(g_u8EndFlag == 0)
        {
            if(--u32TimeOutCnt == 0)
            {
                printf("Wait for I2C Tx finish time-out!\n");
                goto lexit;
            }
        }
        g_u8EndFlag = 0;

        /* Make sure I2C0 STOP already */
        u32TimeOutCnt = I2C_TIMEOUT;
        while(I2C0->CTL0 & I2C_CTL0_STO_Msk)
        {
            if(--u32TimeOutCnt == 0)
            {
                printf("Wait for I2C STOP ready time-out!\n");
                goto lexit;
            }
        }

        /* Wait write operation complete */
        CLK_SysTickDelay(10000);

        /* I2C function to read data from slave */
        s_I2C0HandlerFn = (I2C_FUNC)I2C_MasterRx;

        g_u8DataLen = 0;
        g_u8DeviceAddr = 0x50;

        I2C_SET_CONTROL_REG(I2C0, I2C_CTL_STA);

        /* Wait I2C Rx Finish */
        u32TimeOutCnt = I2C_TIMEOUT;
        while(g_u8EndFlag == 0)
        {
            if(--u32TimeOutCnt == 0)
            {
                printf("Wait for I2C Rx finish time-out!\n");
                goto lexit;
            }
        }

        /* Make sure I2C0 STOP already */
        u32TimeOutCnt = I2C_TIMEOUT;
        while(I2C0->CTL0 & I2C_CTL0_STO_Msk)
        {
            if(--u32TimeOutCnt == 0)
            {
                printf("Wait for I2C STOP ready time-out!\n");
                goto lexit;
            }
        }

        /* Compare data */
        if(g_u8RxData != g_au8TxData[2])
        {
            printf("I2C Byte Write/Read Failed, Data 0x%x\n", g_u8RxData);
            goto lexit;
        }
    }
    printf("I2C Access EEPROM Test OK\n");

lexit:

    while(1);
}
