///////////////////////////////////////////////////////////////////////
//TWI initializing
void twi_init(){
	
	TWBR = 100;						
	TWSR = (0<<TWPS1)|(0<<TWPS0);							//sets SCL Frequency to 19,6 kHz .. SCLfrequency = CLKio/(16+2*(TWBR)*4^TWPS)
	TWCR = (1<<TWEA)|(1<<TWEN);								//enables TWI interface, and sets controlling ACK bit , see datasheet
}

///////////////////////////////////////////////////////////////////////
//TWI error handling
void twi_error(){
	TWCR = (1<<TWINT)|(1<<TWEN)|(1<<TWSTO);		//send Stop condition
	TWCR = (0<<TWEN);							//disable TWI interface
	twi_init();									//call twi_init for new initialization
	twi_error_tmp = 0xFF;						//set twi_error_tmp to 0xFF --> signalize that a error occur
}

///////////////////////////////////////////////////////////////////////
//TWI test TWINT flag with avoiding infinite loop
void twi_twint_flag(){
		uint16_t tmpx;			
		for(tmpx= 0;tmpx<5000;tmpx++){
		if((TWCR & (1<<TWINT)) != 0){
			break;
		}
	}			
}

///////////////////////////////////////////////////////////////////////
//I²C or TWI Bus Routine 2 Bytes

void twi_read_Byte(uint8_t slave_address, uint8_t command, uint8_t byteAnzahlRead){
	
	uint16_t tmp = 0;
	twi_error_tmp= 0;
	for(tmp= 0;tmp<5000;tmp++){
		if((PIND & (1<<PD0)) == 1){
			if((PIND & (1<<PD1)) == 1){
				break;}
		}}

	TWCR = (1<<TWINT)|(1<<TWSTA)|(1<<TWEN);
	twi_twint_flag();
	if((TWSR & 0xF8)!= 0x08){
		twi_error();
		if(twi_error_tmp == 0xFF){	
			return;}}
	
	TWDR = slave_address;
	TWCR = (1<<TWINT)|(1<<TWEN);						//send slave address
	twi_twint_flag();
	if((TWSR & 0xF8)!= 0x18){
		twi_error();									//twi error handling
		if(twi_error_tmp == 0xFF){						//if error occured get out of function
			return;}}
	
	TWDR = command;
	TWCR = (1<<TWINT)|(1<<TWEN);						//send command
	twi_twint_flag();
	if((TWSR & 0xF8)!= 0x28){
		twi_error();
		if(twi_error_tmp == 0xFF){
			return;}}
	
	TWCR = (1<<TWINT)|(1<<TWSTA)|(1<<TWEN);				//send repeated start condition
	twi_twint_flag();
	if((TWSR & 0xF8)!= 0x10){
		twi_error();
		if(twi_error_tmp == 0xFF){					
			return;}}
		
	TWDR = slave_address + 0x01;
	TWCR = (1<<TWINT)|(1<<TWEN);						//send slave address again
	twi_twint_flag();
	if((TWSR & 0xF8)!= 0x40){
		twi_error();
		if(twi_error_tmp == 0xFF){
			return;}}
	
	if(byteAnzahlRead == 1){							// if byteAnzahlRead is 1 --> only one byte is read via TWI communication
		goto only_1ByteData;}
		
	TWCR = (1<<TWINT)|(1<<TWEA)|(1<<TWEN);
	twi_twint_flag();
	if((TWSR & 0xF8)!= 0x50){				
		twi_error();
		if(twi_error_tmp == 0xFF){
			return;}}
		
	DataByte1_receive_twi = TWDR;						//receive Data byte 1
	
only_1ByteData:		
	TWCR = (1<<TWINT)|(0<<TWEA)|(1<<TWEN);
	twi_twint_flag();
	if((TWSR & 0xF8)!= 0x58){
		twi_error();
		if(twi_error_tmp == 0xFF){
			return;}}
			
	DataByte2_receive_twi = TWDR;						//receive Data byte 2
	
	TWCR = (1<<TWINT)|(1<<TWEN)|(1<<TWSTO);				//send stop conditon
	
}









///////////////////////////////////////////////////////////////////////
//Read lp1 safety flags
void lp1_flags_read(){
	
	uint8_t	empty_tmp1_safety = 0;
	uint8_t	empty_tmp2_safety = 0;
	uint8_t	full_tmp1_safety = 0;
	uint8_t	full_tmp2_safety = 0;
	uint8_t empty_tmp_chargeAL = 0;
	uint8_t	full_tmp_chargeAL = 0;
	uint8_t	safety_tmp1 = 0;
	uint8_t	safety_tmp2 = 0;
	
	twi_read_Byte(0x16,0x3a,2);									//Read 2 Bytes 
	if(twi_error_tmp == 0x00){	
		empty_tmp2_safety = DataByte2_receive_twi & (1<<PUV); 
		empty_tmp1_safety = DataByte1_receive_twi & (1<<CUV); 
		full_tmp2_safety = DataByte2_receive_twi & (1<<POV);  
		full_tmp1_safety = DataByte1_receive_twi & (1<<COV);  
		safety_tmp1	= DataByte1_receive_twi & ((1<<HOCD)|(1<<HOCC)|(1<<HSC)|(1<<EUV)|(1<<HWDG)|(1<<BOT));
		safety_tmp2	= DataByte2_receive_twi & ((1<<OCC2)|(1<<OCD2)|(1<<OCC)|(1<<OCD)|(1<<OTC)|(1<<OTD));
		
		if((empty_tmp1_safety | empty_tmp2_safety)!= 0){		
			count_tmp2TM++;
			if(count_tmp2TM >2){
			LP1_logic_tmp = 0x00;
			count_tmp2TM = 0x00; }								
		}
		if((full_tmp1_safety | full_tmp2_safety) != 0){
			count_tmp2TM++;
			if(count_tmp2TM >2){
			LP1_logic_tmp = 0xFF;
			count_tmp2TM = 0x00;}
			}								
		
	}
	
	twi_read_Byte(0x16,0x48,2);								
	if(twi_error_tmp == 0x00){
		empty_tmp_chargeAL = DataByte2_receive_twi & (1<<DC); 
		full_tmp_chargeAL = DataByte2_receive_twi & (1<<CC);  
		if(empty_tmp_chargeAL != 0){
			count_tmp3TM++;
			if(count_tmp3TM >0){
			LP1_logic_tmp = 0x00;
			count_tmp3TM = 0x00;}								
		}
		if(full_tmp_chargeAL != 0){
			count_tmp3TM++;
			if(count_tmp3TM >0){
			LP1_logic_tmp = 0xFF;
			count_tmp3TM = 0x00;}								
		}
	} 
	}