The DS1683 from Analog Devices is a recent introduction with an RC oscillator tailored for elapsed time and event counting. It offers an application the robustness discussed earlier with the absence of a crystal or battery. Once the alarms are set in the device, there is no need to communicate with it from a microcontroller.  The time register is one quarter second resolution and is 32-bits wide, translating to a maximum of thirty four years of elapsed time accumulation. The EVENT register is 16-bits, which is a count of each time a high to low transition on the EVENT pin is detected. There is a separate alarm register for each of the EVENT and ELAPSED TIME registers. The TIME, EVENT, and ALARM registers are all internally stored in EEPROM in the DS1683, with a write endurance of 50 k writes over temperature.