09_eeprom

How to write to and read from EEPROM.

File(s):

• arch/avr/tutorials/09_eeprom/eeprom.c

0xAB is written to EEPROM address 0x000C, read back and reported over UART at 115200 BAUD, 8 Data Bits, No Parity and 1 Stop Bit.

<avr/eeprom.h> can also be used. It is not neccessary to use an explicit EEPROM address. The compiler will allocate a unique address if the EEMEM prefix is used. For example:

#include <stdint.h>
#include <avr/eeprom.h>
 
EEMEM uint16_t ee_setting;
 
int main(void)
{
    uint16_t value;
 
    // Load value from EEPROM
    value = eeprom_read_word(&ee_setting);
    // Modify value
    value += 1;
    // Commit new value to EEPROM
    eeprom_write_word(&ee_setting, value);
    eeprom_busy_wait();
}