i2c.h

#ifndef _I2C_H
#define _I2C_H

#include <avr/io.h>

/* Definitions for I2C */
#define I2C_OUT_PORT            PORTD       /* port for I2C */
#define I2C_IN_PORT             PIND        /* input pin from I2C (SDA) */
#define I2C_DDR                 DDRD        /* pin direction bit */

#define I2C_SCL                 PORTD0      /* I2C SCL (serial clock) pin */
#define I2C_SDA                 PORTD1      /* I2C SDA (serial data) pin */
#define I2C_INT                 PORTD2      /* I2C INT (interrupt) pin */

/*! \brief MACRO => set SDA to high */
#define P_SDA_ON        (I2C_OUT_PORT |= _BV(I2C_SDA))
/*! \brief MACRO => set SDA to low */
#define P_SDA_OFF       (I2C_OUT_PORT &= ~_BV(I2C_SDA))
/*! \brief MACRO => set SCL to high */
#define P_SCL_ON        (I2C_OUT_PORT |= _BV(I2C_SCL))
/*! \brief MACRO => set SDA to low */
#define P_SCL_OFF       (I2C_OUT_PORT &= ~_BV(I2C_SCL))

/*! \brief MACRO => set SDA and SCL as outputs */
#define SET_I2C_OUT     (I2C_DDR |= (_BV(I2C_SDA) | _BV(I2C_SCL)))
/*! \brief MACRO => set SDA as input and SCL as output */
#define SET_I2C_IN      (I2C_DDR |= _BV(I2C_SCL), I2C_DDR &= ~_BV(I2C_SDA))

/*! \brief MACRO => read PCF8583 INT pin */
#define GET_INT_STAT            (I2C_IN_PORT & _BV(I2C_INT))

void I2C_Set_Address(uint8_t, uint8_t);     /* Set I2C low address and type of operation */
void I2C_Start(void);               /* Generate start condition */
void I2C_Stop(void);                /* Generate stop condition */
void I2C_Write_B (uint8_t);         /* Write one byte to temporary register */
uint8_t I2C_Read_B (uint8_t);           /* Read one byte from I2C */
uint8_t I2C_Ack_In(void);           /* Generate ACK pulse for slave present testing */
void I2C_NoAck_Out(void);           /* Generate NON ACK for slave to stop next reading */
void I2C_Ack_Out(void);             /* Generate ACK for slave for next reading */ 
void I2C_Write_Block_W(uint16_t *);     /* Write block of word to I2C */
void I2C_Read_Block(uint8_t , uint8_t *);   /* Read block from I2C */
void I2C_Wait(void);                            /* Wait for I2C */

#endif