ATMEGA128RFA1_11 Datasheet, PDF (22/560 Pages) ATMEL Corporation – 8-bit Microcontroller with Low Power 2.4GHz Transceiver for ZigBee and IEEE 802.15.4

call EEPROM_write
…
C Code Example
void EEPROM_write(unsigned int uiAddress, unsigned char ucData)
{
/* Wait for completion of previous erase/write */
while(EECR & (1<<EEPE))
;
/* Set up address */
EEAR = uiAddress;
EEDR = 255;
/* Write logical one to EEMPE and enable erase only*/
EECR = (1<<EEMPE) + (1<<EEPM0);
/* Start eeprom erase by setting EEPE */
EECR |= (1<<EEPE);
/* Wait for completion of erase */
while(EECR & (1<<EEPE))
;
/* Set up Data Registers */
EEDR = ucData;
/* Write logical one to EEMPE and enable write only */
EECR = (1<<EEMPE) + (2<<EEPM0);
/* Start eeprom write by setting EEPE */
EECR |= (1<<EEPE);
}
Although the code for separate erase/write operations is more complex it is
recommended over the atomic operation. The erase operation can be omitted if the
target EEPROM byte already contains the value 255 (e.g. after a chip erase without the
EESAVE fuse set).
Assembly Code Example (Atomic Operation)
EEPROM_atomic_write:
; Wait for completion of previous write
sbic EECR,EEPE
rjmp EEPROM_atomic_write
; Set up address (r18:r17) in address register
out EEARH, r18
out EEARL, r17
; Write data (r16) to Data Register
out EEDR,r16
; Write logical one to EEMPE
sbi EECR,EEMPE
; Start eeprom write by setting EEPE
sbi EECR,EEPE
ret
22 _{ATmega128RFA1}
8266C-MCU Wireless-08/11