frage zu avr-lib eeprom_write_byte

static __inline__ void eeprom_write_byte (uint8_t *__p, uint8_t __value)

{

    do {} while (!eeprom_is_ready ());

#if  defined(EEPM0) && defined(EEPM1)

    EECR = 0;    /* Set programming mode: erase and write.  */

#elif  defined(EEPM0) || defined(EEPM1)

# warning "Unknown EECR register, eeprom_write_byte() has become outdated."

#endif

#if  E2END <= 0xFF

    EEARL = (size_t)__p;

#else

    EEAR = (size_t)__p;

#endif

    EEDR = __value;

    __asm__ __volatile__ (

        "/* START EEPROM WRITE CRITICAL SECTION */\n\t"

        "in  r0, %[__sreg]    \n\t"

        "cli        \n\t"

        "sbi  %[__eecr], %[__eemwe]  \n\t"

        "sbi  %[__eecr], %[__eewe]  \n\t"

        "out  %[__sreg], r0    \n\t"

        "/* END EEPROM WRITE CRITICAL SECTION */"

        :

        : [__eecr]  "i" (_SFR_IO_ADDR(EECR)),

          [__sreg]  "i" (_SFR_IO_ADDR(SREG)),

          [__eemwe] "i" (EEMWE),

          [__eewe]  "i" (EEWE)

        : "r0"

    );

}