Card like electronic equipment, such as a security digital (SD) memory card, includes a CPU, a real time clock (RTC) for counting time data; a FLASH ROM for storing the time data read out from the RTC into a covered RAM area of the ROM; and a lithium ion battery for supplying driving power to the RTC even when the SD memory card is not connected to a host personal computer, in order to enhance security of the contents data, e.g. copyright, protected by the CPU in the SD memory card.