#include <avr/io.h>
#include <avr/twi.h>
#include <avr/interrupt.h>

// init master
//
//
void init_twi_master (uint8_t twbr) {

	// set the scl
	TWBR = twbr;
	TWCR = _BV(TWEN);
}

// send data
//
//
int main (void) {

	init_twi_master (13);
	DDRB = 0xFF;
	uint16_t sleep;
	uint8_t i = 1;
	while (1) {
		PORTB = ~TWSR;
		// send start
		TWCR = _BV(TWINT) | _BV(TWSTA) | _BV(TWEN);
		while (!(TWCR & _BV(TWINT)));
		PORTB = ~TWSR;
		
		// send the addr
		TWDR = (1<<1) | 0;
		TWCR = _BV(TWINT) | _BV(TWEN);
		while (!(TWCR & _BV(TWINT)));
		PORTB = ~TWSR;
		
		if ((TWSR & 0xF8) != TW_MT_SLA_ACK){
			//error(TWSR, 0x01);
		}
		//while(1){
			TWDR = i;
			TWCR = _BV(TWINT) | _BV(TWEN);
			while (!(TWCR & _BV(TWINT)));
			PORTB = ~TWSR;
			
			if((TWSR & 0xF8) != TW_MT_DATA_ACK){
				//error(TWSR, 0x02);
			}
		//	i++;
		//}
		
		// send stop
		TWCR = _BV(TWINT) | _BV(TWSTO) | _BV(TWEN) | _BV(TWEA);
		while( !(TWCR & _BV(TWSTO)) );
		//while (!(TWCR & _BV(TWINT)));
		PORTB = ~TWSR;
		//sleep = 65535;
		//while(sleep--);
		//TWCR = TWCR & ~(_BV(TWEN));
		i++;
	}
	
	return 0;
}