Only 512 EEPROM. Sorry I was thinking 328 with 2k Ram. 300 events would be more realistic with 1k. Unless you only wanted 30 seconds accuracy. Then I could do events that are 2 hours apart. 4 hours apart would take an extra byte. That is not a limitation. If you wanted it to standalone for 10 days then it would only be able to log about 4 events per hour, assuming none happen while you're sleeping. Seems a little tight for 1k of Ram. How about 1 minute resolution? Or 328. Or SD card.