US Patent 7840621 Electronic apparatus and its control program

In an electronic apparatus having multiple functions such as a scientific electronic calculator, some of the multiple functions are set to be disabled according to need. Function disabling information (protection data) including disabled applications, protect display screen and protection period is stored on a memory card. When the memory card installed in a card slot of the electronic apparatus is detected, the function disabling information is read out and transferred onto corresponding memory areas of a system area in a flash ROM of the apparatus, and a protection display screen is displayed on a display unit, indicating that some of the multiple functions are disabled. Then, only “EXE” key operation is accepted and the function corresponding to the disabled application is disabled, and a function selecting menu screen is displayed, in which a start-up disabled mark M is added to an icon of the disabled application and a protection remaining time T is added.