In our business,were engaged in electronic operated water dispensing machine and only powered up on working hours. . What I am looking for is an IC that would log every transaction made by the buttons used for dispensing. Is there any IC that is capable of hold this data without supply on non working hours? Together with the date and time even if the machine is unplugged? Is that possible even if an internal supply is not present? Im just protecting the lost of data in case an internal supply is present then its battery will suddenly malfunction,or tampered by another engineer or technician.