#include "avr/io.h"

uint8_t appdata_0 __attribute__((address (0x8F00)));
uint8_t appdata_1 __attribute__((address (0x8F01)));
uint8_t appdata_2 __attribute__((address (0x8F02)));

int main (void)
{
 appdata_0 = 0xAB;
 appdata_1 = 0xCD;
 appdata_2 = 0xEF;
 CPU_CCP = CCP_SPM_gc;
 NVMCTRL.CTRLA = 0x03; // ERWP Erase and write page (NVMCTRL.ADDR selects which memory)
 
 USERROW.USERROW11 = 0x11;
 USERROW.USERROW12 = 0x22;
 USERROW.USERROW13 = 0x33;
 USERROW.USERROW14 = 0x44;
 USERROW.USERROW15 = 0x55;
 USERROW.USERROW16 = 0x66;
 USERROW.USERROW17 = 0x77;
 CPU_CCP = CCP_SPM_gc;
 NVMCTRL.CTRLA = 0x03; // ERWP Erase and write page (NVMCTRL.ADDR selects which memory)

 while(1)
    {
    }
}