//============================================================================
// Name        : test_A.cpp
// Author      : Adarsh Kumar
// Version     :
// Copyright   : Your copyright notice
// Description : Hello World in C++, Ansi-style
//============================================================================

#include <stdio.h>
#include <string.h>
#include <stdlib.h> // system()
#include <unistd.h> // sleep()
#include <fcntl.h>  // oflag like O_RDWR
#include <linux/i2c-dev.h>
#include <sys/ioctl.h>

char Readbyte(char address);



char file_I2C1_DEV[30] = "/dev/i2c-0";
int  file;

int addr_AD5933 = 0b00001101;      // The I2C address of AD5933

int main()
{
    printf("I2C Interface Project!\n");

    if((file = open(file_I2C1_DEV,O_RDWR)) < 0)
    {
        perror("Failed to open the i2c bus");
        exit(1);
    }

    if(ioctl(file,I2C_SLAVE,addr_AD5933) < 0)
    {
        printf("Failed to acquire bus access and/or talk to slave.\n");
        exit(1);
    }

char temp;

        temp = Readbyte(82);
        printf("%d\n",temp);
        sleep(1);

}

char Readbyte(char address)
{
    char data;
    char buf[10] = {0};

    buf[0] = address;

    if(write(file,buf,1) != 1)
    {
        /* ERROR HANDLING: i2c transaction failed */
        printf("Failed to write to the i2c bus.\n");
    }

    // Using I2C Read
    if (read(file,buf,1) != 1)
    {
        /* ERROR HANDLING: i2c transaction failed */
        printf("Failed to read from the i2c bus.\n");
        }
    else
    {
        data = buf[0];
        }

    //BCD To Decimal Conversion
    if(address == 0)    //remove MSB bit in case of second
    {
        data = (((data & 0x70) >> 4) * 10) + (data & 0x0F);
    }
    else
    {
        data = (((data & 0xF0) >> 4) * 10) + (data & 0x0F);
   }

    return data;

}