Adresse erkennen vom Slave mit USI

/*##############################################################################

  Name  : USI TWI Slave driver - I2C/TWI-EEPROM

  Version  : 1.3  - Stable

  autor  : Martin Junghans  jtronics@gmx.de

  page  : www.jtronics.de

  License  : GNU General Public License 

  Created from Atmel source files for Application Note AVR312: 

  Using the USI Module as an I2C slave like a I2C-EEPROM.

//############################################################################*/

#include   <stdlib.h>

#include   <avr/io.h>

#include   <avr/interrupt.h>

#include   <avr/pgmspace.h>

//################################################################## USI-TWI-I2C

#include   "usiTwiSlave.h"         

// Note: The LSB is the I2C r/w flag and must not be used for addressing!

#define   SLAVE_ADDR_ATTINY  0x52 //    0b00110100

#ifndef   F_CPU

#define   F_CPU 16000000UL

#endif

//####################################################################### Macros

#define uniq(LOW,HEIGHT)  ((HEIGHT << 8)|LOW)        // Create 16 bit number from two bytes

#define LOW_BYTE(x)          (x & 0xff)              // Get low byte from 16 bit number  

#define HIGH_BYTE(x)         ((x >> 8) & 0xff)        // Get high byte from 16 bit number

#define sbi(ADDRESS,BIT)   ((ADDRESS) |= (1<<(BIT)))  // Set bit

#define cbi(ADDRESS,BIT)   ((ADDRESS) &= ~(1<<(BIT)))// Clear bit

#define  toggle(ADDRESS,BIT)  ((ADDRESS) ^= (1<<BIT))  // Toggle bit

#define  bis(ADDRESS,BIT)  (ADDRESS & (1<<BIT))      // Is bit set?

#define  bic(ADDRESS,BIT)  (!(ADDRESS & (1<<BIT)))    // Is bit clear?

//#################################################################### Variables

  uint16_t   word=0;        // Counter

  uint8_t    byte1, byte2;

  uint16_t  buffer;

  uint8_t    high,low = 0;  // Variables used with uniq (high and low byte)

//################################################################# Main routine

int main(void)

  {   

  cli();  // Disable interrupts

  usiTwiSlaveInit(SLAVE_ADDR_ATTINY);  // TWI slave init

  sei();  // Re-enable interrupts

  for (int i = 0; i < 10; i++)  // Fill buffers with arbitrary data

    txbuffer[i] = i + 10;

  for (int i = 0; i < 4; i++)

    rxbuffer[i] = i + 20;

    while(1)

      {

      //############################################ Read data from reception buffer

      // 8 bit variables

       byte1  = rxbuffer[0];

      byte2  = rxbuffer[1];

      // 2 8 bit variables converted into a 16 bit number

      low    = rxbuffer[2];

      high  = rxbuffer[3];

      word  = uniq(low,high);

      //########################################## Write data to transmission buffer

      // 8 bit variables

      txbuffer[0]= byte1;

      txbuffer[1]= byte2;

      // 16 bit variable broken up into its high and low byte

      buffer    = word;

      txbuffer[2]  = LOW_BYTE(buffer);

      txbuffer[3]  = HIGH_BYTE(buffer);

      //############################################################################

    } //end.while

  } //end.main