Kod: Markera allt
/* Write directly the value 0x55 to the EEPROM */
alfa=0x55;
/* or indirectly by using a pointer */
ptr_to_eeprom=&alfa;
*ptr_to_eeprom=0x55;
Kod: Markera allt
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);
}
Kod: Markera allt
CodeVisionAVR - 3.14 Accessing the EEPROM
Accessing the AVR internal EEPROM is accomplished using global variables, preceded by the
keyword eeprom.
Example:
/* The value 1 is stored in the EEPROM during chip programming */
eeprom int alfa=1;
eeprom char beta;
eeprom long array1[5];
/* The string is stored in the EEPROM during chip programming */
eeprom char string[]=”Hello”;
void main(void) {
int i;
/* Pointer to EEPROM */
int eeprom *ptr_to_eeprom;
/* Write directly the value 0x55 to the EEPROM */
alfa=0x55;
/* or indirectly by using a pointer */
ptr_to_eeprom=&alfa;
*ptr_to_eeprom=0x55;
/* Read directly the value from the EEPROM */
i=alfa;
/* or indirectly by using a pointer */
i=*ptr_to_eeprom;
}
Pointers to the EEPROM always use 16 bits.
