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void I2C::init(){
   TWBR = (uint8_t)TWBR_val;
}

bool I2C::startTransmit(uint8_t address)
{
   // reset TWI control register
   TWCR = 0;
   // transmit START condition
   TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
   // wait for end of transmission
   while( !(TWCR & (1<<TWINT)) );
   
   // check if the start condition was successfully transmitted
   if((TWSR & 0xF8) != TW_START){ return false; }
   
   // load slave address into data register
   TWDR = address;
   // start transmission of address
   TWCR = (1<<TWINT) | (1<<TWEN);
   // wait for end of transmission
   while( !(TWCR & (1<<TWINT)) );
   
   // check if the device has acknowledged the READ / WRITE mode
   uint8_t twst = TW_STATUS & 0xF8;
   if ( (twst != TW_MT_SLA_ACK) && (twst != TW_MR_SLA_ACK) ) return false;
   
   return true;
}

void I2C::startTransmitWait(uint8_t address)
{
   uint8_t   twst;

   while ( 1 )
   {
      // send START condition
      TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN);
      
      // wait until transmission completed
      while(!(TWCR & (1<<TWINT)));
      
      // check value of TWI Status Register. Mask prescaler bits.
      twst = TW_STATUS & 0xF8;
      if ( (twst != TW_START) && (twst != TW_REP_START)) continue;
      
      // send device address
      TWDR = address;
      TWCR = (1<<TWINT) | (1<<TWEN);
      
      // wail until transmission completed
      while(!(TWCR & (1<<TWINT)));
      
      // check value of TWI Status Register. Mask prescaler bits.
      twst = TW_STATUS & 0xF8;
      if ( (twst == TW_MT_SLA_NACK )||(twst ==TW_MR_DATA_NACK) )
      {
         /* device busy, send stop condition to terminate write operation */
         TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
         
         // wait until stop condition is executed and bus released
         while(TWCR & (1<<TWSTO));
         
         continue;
      }
      //if( twst != TW_MT_SLA_ACK) return 1;
      break;
   }

}/* i2c_start_wait */

void I2C::stopTransmit()
{
    /* send stop condition */
    TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
    // wait until stop condition is executed and bus released
    while(TWCR & (1<<TWSTO));
}

bool I2C::write(uint8_t data)
{
   // load data into data register
   TWDR = data;
   // start transmission of data
   TWCR = (1<<TWINT) | (1<<TWEN);
   // wait for end of transmission
   while( !(TWCR & (1<<TWINT)) );
   
   if( (TWSR & 0xF8) != TW_MT_DATA_ACK ){ return false; }
   
   return true;
}

uint8_t I2C::readAck()
{
   // start TWI module and acknowledge data after reception
   TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
   // wait for end of transmission
   while( !(TWCR & (1<<TWINT)) );
   // return received data from TWDR
   return TWDR;
}

uint8_t I2C::readNAck()
{
   // start receiving without acknowledging reception
   TWCR = (1<<TWINT) | (1<<TWEN);
   // wait for end of transmission
   while( !(TWCR & (1<<TWINT)) );
   // return received data from TWDR
   return TWDR;
}

#include "ITG3205.h"


void ITG3205::init(I2C *i2c, UART *uart){
   this->i2c=i2c;
   this->uart=uart;
   
   uart->writeLn("Init ITG3205");
   
   i2c->startTransmit(GYRO_ADDR);
   i2c->write(G_PWR_MGM);
   i2c->write(0x00);
   i2c->stopTransmit();
   
   i2c->startTransmit(GYRO_ADDR);
   i2c->write(G_SMPLRT_DIV);
   i2c->write(0x07);
   i2c->stopTransmit();
   
   i2c->startTransmit(GYRO_ADDR);
   i2c->write(G_DLPF_FS);
   i2c->write(0x1E);
   i2c->stopTransmit();
   
   i2c->startTransmit(GYRO_ADDR);
   i2c->write(G_INT_CFG);
   i2c->write(0x00);
   i2c->stopTransmit();
}

void ITG3205::getXdata(uint8_t *lowByte, uint8_t *hightByte){
   
   //========Получение младшего байта X====
   i2c->startTransmit(GYRO_ADDR);
   i2c->write(GYRO_XOUT_L);
   i2c->stopTransmit();
   
   i2c->startTransmit(GYRO_ADDR);
   *lowByte = i2c->readAck();
   i2c->stopTransmit();
   //======================================
   
   //========Получение старшего байта X====
   i2c->startTransmit(GYRO_ADDR);
   i2c->write(GYRO_XOUT_H);
   i2c->stopTransmit();
   
   i2c->startTransmit(GYRO_ADDR);
   *hightByte = i2c->readAck();
   i2c->stopTransmit();
   //======================================
}