I2C software seltsames Verhalten

 #include "i2cmaster.h"

 #define AdresseSlave  0x16    // device address of EEPROM 24C02, see datasheet

 #include <avr/io.h>

 #include <util/delay.h>

 int main(void)

 {

   unsigned char ret;

   smb_init();                             // initialize I2C library

   // write 0x75 to EEPROM address 5 (Byte Write)

   smb_start_wait(AdresseSlave+SMB_WRITE);     // set device address and write mode

   smb_write(0x05);                        // write address = 5

   smb_write(0x75);                        // write value 0x75 to EEPROM

   smb_stop();                             // set stop conditon = release bus

   // read previously written value back from EEPROM address 5

   smb_start_wait(AdresseSlave+SMB_WRITE);     // set device address and write mode

   smb_write(0x05);                        // write address = 5

   smb_rep_start(AdresseSlave+SMB_READ);       // set device address and read mode

   ret = smb_readNak();                    // read one byte from EEPROM

   smb_stop();

   for(;;);

return 0;   

 }