/*---------------------------------------------------------------------------------------------------------*/
/*                                                                                                         */
/* Copyright(c) 2017 Nuvoton Technology Corp. All rights reserved.                                         */
/*                                                                                                         */
/*---------------------------------------------------------------------------------------------------------*/

//***********************************************************************************************************
//  Nuvoton Technoledge Corp. 
//  Website: http://www.nuvoton.com
//  E-Mail : MicroC-8bit@nuvoton.com
//  Date   : Jun/21/2017
//***********************************************************************************************************

//***********************************************************************************************************
//  File Function: N76E003 I2C demo code, Slave Address of 24LC64 = 0xA0
//
//   ____________           ______________ 
//  |            |   SDA    |             |
//  |            |<-------->|             |
//  |            |          |             |
//  |N76E003(M) |          |   24LC64(S) |
//  |            |   SCL    |             |
//  |            |--------->|             |
//  |____________|          |_____________|
//
//  Microchip I2C EEPROM 24xx64 (64K Bit) is used as the slave device.  
//  The page size are 32Byte. Total are 256 page.
//  If verification passes, Port3 will show 0x78. If there is any failure
//  occured during the progress, Port3 will show 0x00.
//***********************************************************************************************************

#include "N76E003.h"
#include "SFR_Macro.h"
#include "Function_define.h"
#include "Common.h"
#include "Delay.h"

#define SYS_CLK_EN              0
#define SYS_SEL                 2
#define SYS_DIV_EN              0                   //0: Fsys=Fosc, 1: Fsys = Fosc/(2*CKDIV)
#define SYS_DIV                 1
#define I2C_CLOCK               2

#define EEPROM_SLA              0xA0
#define EEPROM_WR               0
#define EEPROM_RD               1

#define LED                     P3
#define PAGE_SIZE               32
#define PAGE_NUMBER             4

#define ERROR_CODE              0x78
#define TEST_OK                 0x00

bit I2C_Reset_Flag;
//========================================================================================================
void Init_I2C(void)
{
        P13_OpenDrain_Mode;                    // Modify SCL pin to Open drain mode. don't forget the pull high resister in circuit
        P14_OpenDrain_Mode;                    // Modify SDA pin to Open drain mode. don't forget the pull high resister in circuit
    
    /* Set I2C clock rate */
    I2CLK = I2C_CLOCK; 

    /* Enable I2C */
    set_I2CEN;                                   
}
//========================================================================================================
void I2C_SI_Check(void)
{
        if (I2STAT == 0x00)
        {
                I2C_Reset_Flag = 1;
                set_STO;
                SI = 0;
                if(SI)
                {
                        clr_I2CEN;
                        set_I2CEN;
                        clr_SI;
                        clr_I2CEN;        
                }     
        }    
}

void One_Page_Read(UINT8 u8PageNumber,UINT8 u8DAT)
{
    UINT8  u8Count;
    UINT16 u16Address;

    u16Address = (UINT16)u8PageNumber*32;

    /* Step1 */
    set_STA;                                /* Send Start bit to I2C EEPROM */
    clr_SI;
    while (!SI);
    if (I2STAT != 0x08)                     /* 0x08:  A START condition has been transmitted*/
    {
        I2C_Reset_Flag = 1;
                printf("\nI2C 'Send STA' error");
                goto Read_Error_Stop;
    }

    /* Step2 */
    I2DAT = (EEPROM_SLA | EEPROM_WR);       /* Send (SLA+W) to EEPROM */
    clr_STA;                                /* Clear STA and Keep SI value in I2CON */    
    clr_SI;
    while (!SI);
    if (I2STAT != 0x18)                     /* 0x18: SLA+W has been transmitted; ACK has been received */              
    {
                I2C_Reset_Flag = 1;
        printf("\nI2C 'Send SLA+W' error");
                goto Read_Error_Stop;
    }

    /* Step3 */
    I2DAT = HIBYTE(u16Address);             /* Send I2C EEPROM's High Byte Address */
    clr_SI;
    while (!SI);
    if (I2STAT != 0x28)                     /* 0x28:  Data byte in S1DAT has been transmitted; ACK has been received */              
    {
                I2C_Reset_Flag = 1;
        printf("\nI2C 'Send I2C High Byte Address' error");
                goto Read_Error_Stop;
    }

    /* Step4 */
    I2DAT = LOBYTE(u16Address);             /* Send I2C EEPROM's Low Byte Address */
    clr_SI;
    while (!SI);
    if (I2STAT != 0x28)                     /* 0x28:  Data byte in S1DAT has been transmitted; ACK has been received */             
    {
                I2C_Reset_Flag = 1;
                printf("\nI2C 'Send I2C Low Byte Address' error");
                goto Read_Error_Stop;
    }

    /* Step5 */
    set_STA;                                /* Repeated START */
    clr_SI; 
    while (!SI);
    if (I2STAT != 0x10)                     /* 0x10: A repeated START condition has been transmitted */
    {
                I2C_Reset_Flag = 1;
        printf("\nI2C 'Send STA' error");
                goto Read_Error_Stop;
    }

    /* Step6 */
    clr_STA;                                /* Clear STA and Keep SI value in I2CON */
    I2DAT = (EEPROM_SLA | EEPROM_RD);       /* Send (SLA+R) to EEPROM */
    clr_SI;
    while (!SI);
    if (I2STAT != 0x40)                     /* 0x40:  SLA+R has been transmitted; ACK has been received */              
    {
                I2C_Reset_Flag = 1;
        printf("\nI2C 'Send SLA+R' error");
                goto Read_Error_Stop;
    }

    /* Step7 */                             /* Verify I2C EEPROM data */
    for (u8Count = 0; u8Count <PAGE_SIZE; u8Count++)
    {
        set_AA;                             /* Set Assert Acknowledge Control Bit */
        clr_SI;
        while (!SI);
        if (I2STAT != 0x50)                 /* 0x50:Data byte has been received; NOT ACK has been returned */              
        {
                        I2C_Reset_Flag = 1;
            printf("\nI2C 'No Ack' error");
                        goto Read_Error_Stop;
        }
       
        if (I2DAT != u8DAT)                 /* Send the Data to EEPROM */    
        {
                        I2C_Reset_Flag = 1;
                        printf("\nI2C 'Read data' error");
            goto Read_Error_Stop;
        }
        u8DAT = ~u8DAT; 
    }

    /* Step8 */
    clr_AA;                                 /* Send a NACK to disconnect 24xx64 */
    clr_SI;
    while (!SI);
    if (I2STAT != 0x58)                     /* 0x58:Data byte has been received; ACK has been returned */
    {
        I2C_Reset_Flag = 1;
        printf("\nI2C 'Ack' error");
        goto Read_Error_Stop;
    }
    
    /* Step9 */    
      clr_SI;
    set_STO;
        while (STO)                        /* Check STOP signal */
        {
            I2C_SI_Check();
            if (I2C_Reset_Flag)
                goto Read_Error_Stop;
        }
        
Read_Error_Stop: 
        if (I2C_Reset_Flag)
        {
                I2C_SI_Check();
              printf("\nI2C Read error, test stop");
                I2C_Reset_Flag = 0;
        }
}
//========================================================================================================
void One_Page_Write(UINT8 u8PageNumber,UINT8 u8DAT)
{
    UINT8  u8Count;
    UINT16 u16Address;

    u16Address = (UINT16)u8PageNumber*32;

    /* Step1 */
    set_STA;                                /* Send Start bit to I2C EEPROM */         
    clr_SI;
    while (!SI);
    if (I2STAT != 0x08)                     /* 0x08:  A START condition has been transmitted*/
    {
        I2C_Reset_Flag = 1;
        printf("\nI2C 'Send STA' error");
        goto Write_Error_Stop;
    }

    /* Step2 */
    clr_STA;                                /* Clear STA and Keep SI value in I2CON */
    I2DAT = EEPROM_SLA | EEPROM_WR;         /* Send (SLA+W) to EEPROM */
    clr_SI;
    while (!SI);
    if (I2STAT != 0x18)                     /* 0x18: SLA+W has been transmitted; ACK has been received */             
    {
        I2C_Reset_Flag = 1;
        printf("\nI2C 'Send SLA+W' error");
        goto Write_Error_Stop;
    }

    /* Step3 */
    I2DAT = HIBYTE(u16Address);             /* Send EEPROM's High Byte Address */
    clr_SI;
    while (!SI);
    if (I2STAT != 0x28)                     /* 0x28:  Data byte in S1DAT has been transmitted; ACK has been received */
    {
        I2C_Reset_Flag = 1;
        printf("\nI2C 'Send High byte address' error");
        goto Write_Error_Stop;
    }

    /* Step4 */
    I2DAT = LOBYTE(u16Address);             /* Send EEPROM's Low Byte Address */
    clr_SI;
    while (!SI);
    if (I2STAT != 0x28)                     /* 0x28:  Data byte in S1DAT has been transmitted; ACK has been received */
    {
        I2C_Reset_Flag = 1;
        printf("\nI2C 'Send Low byte address' error");
        goto Write_Error_Stop;
    }

    /* Step5 */
                                            /* Write data to I2C EEPROM */
    for (u8Count = 0; u8Count < PAGE_SIZE; u8Count++)
    {
        I2DAT = u8DAT;                      /* Send data to EEPROM */
        clr_SI;
        while (!SI);
        if (I2STAT != 0x28)                 /* 0x28:  Data byte in S1DAT has been transmitted; ACK has been received */
        {
            I2C_Reset_Flag = 1;
                        printf("\nI2C 'Write Data' error");
            goto Write_Error_Stop;
        }   
        u8DAT = ~u8DAT;        
    }
                                            //After STOP condition, a inner EEPROM timed-write-cycle 
                                            //will occure and EEPROM will not response to outside command
                                            /* 0x18: SLA+W has been transmitted; ACK has been received */
    /* Step6 */
    do
    {
              set_STO;                            /* Set I2C STOP Control Bit */
        clr_SI;
        while (STO)                        /* Check STOP signal */
                {
                    I2C_SI_Check();
                    if (I2C_Reset_Flag)
                        goto Write_Error_Stop;
                }
        
        set_STA;                            /* Check if no ACK is returned by EEPROM, it is under timed-write cycle */
        clr_SI;
        while (!SI);
        if (I2STAT != 0x08)                 /* 0x08:  A START condition has been transmitted*/
        {
            I2C_Reset_Flag = 1;
            printf("\nI2C 'Wait Ready' error");
            goto Write_Error_Stop;
        }

        clr_STA;                            /* Clear STA and Keep SI value in I2CON */
        I2DAT = (EEPROM_SLA | EEPROM_WR);   /* Send (SLA+W) to EEPROM */
        clr_SI;
        while (!SI);
    }while(I2STAT != 0x18);

    /* Step7 */
    set_STO;                                /* Set STOP Bit to I2C EEPROM */
    clr_SI;
        while (STO)                        /* Check STOP signal */
        {
            I2C_SI_Check();
            if (I2C_Reset_Flag)
                goto Write_Error_Stop;
        }
        
Write_Error_Stop: 
        if (I2C_Reset_Flag)
        {
                I2C_SI_Check();
                I2C_Reset_Flag    = 0;
                printf("\nI2C Write error, test stop");
        }
        
        
}
//========================================================================================================
void main(void)
{

    Set_All_GPIO_Quasi_Mode;
        InitialUART0_Timer3(115200);
  
    /* Initial I2C function */
    Init_I2C();                                 //initial I2C circuit
    
    /* page0 R/W */
    printf ("\n\n24LC64 Page0 Write (0x55,0xAA...)...");
    One_Page_Write(0,0x55);                     //page0, write 0x55,0xAA,........

    printf ("\n\n24LC64 Page0 Read...");
    One_Page_Read (0,0x55);                     //page0, read  0x55,0xAA,........

    /* page1 R/W */
    printf ("\n\n24LC64 Page1 Write (0x00,0xFF...)...");
    One_Page_Write(1,0x00);                     //page1, write 0x00,0xFF,........
    printf ("\n\n24LC64 Page1 Read...");
    One_Page_Read (1,0x00);                     //page1, read  0x00,0xFF,........

    /* page2 R/W */
    printf ("\n\n24LC64 Page2 Write (0xAA,0x55...)...");
    One_Page_Write(2,0xAA);                     //page2, write 0xAA,0x55,........
    printf ("\n\n24LC64 Page2 Read...");
    One_Page_Read (2,0xAA);                     //page2, read  0xAA,0x55,........

    /* page3 R/W */
    printf ("\n\n24LC64 Page3 Write (0xFF,0x00...)...");
    One_Page_Write(3,0xFF);                     //page3, write 0xFF,0x00,........
    printf ("\n\n24LC64 Page3 Read...");
    One_Page_Read (3,0xFF);                     //page3, read  0xFF,0x00,........

    /* page255 R/W */
    printf ("\n\n24LC64 Page255 Write (0x0F,0xF0...)...");
    One_Page_Write(255,0x0F);                   //page255, write 0x0F,0xF0,........
    printf ("\n\n24LC64 Page255 Read...");
    One_Page_Read (255,0x0F);                   //page255, read  0x0F,0xF0,........

    /* ==== Test Pass ==== */      
    printf ("\n\N76E003 <--> 24LC64, I2C Demo Code test pass...");

    while (1);
/* =================== */
}