25
4317I–AVR–01/08
AT90PWM2/3/2B/3B
Assembly Code Example
EEPROM_write:
; Wait for completion of previous write
sbic
EECR,EEWE
rjmp
EEPROM_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 EEMWE
sbi
EECR,EEMWE
; Start eeprom write by setting EEWE
sbi
EECR,EEWE
ret
C Code Example
void
EEPROM_write (
unsigned int
uiAddress,
unsigned char
ucData)
{
/*
Wait for completion of previous write
*/
while(EECR & (1<<EEWE))
;
/* Set up address and data registers */
EEAR = uiAddress;
EEDR = ucData;
/*
Write logical one to EEMWE */
EECR |= (1<<EEMWE);
/* Start eeprom write by setting EEWE */
EECR |= (1<<EEWE);
}