PURPOSE: To certainly prevent the damage of a card when the card is inserted in a card slot in a state turned upside down by bisecting the end of circuit wiring including power supplies at every kind and distributing the bisected ends to respective terminals in a left and right symmetric state.

CONSTITUTION: Power supplies (5V/GND), data lines D0-D7, address lines (A0-A7) and control signal lines (CTL) are respectively connected in a left and right symmetric state across the center (2/40 pins = 20 pins in a drawing) of pins (terminals). By this card structure, when cards 3a, 3b having semiconductor circuit elements built therein such as memory cards or IC cards are inserted in card slots 101, 201 in a state turned upside down, both of or one of an apparatus main body 1 and the cards 3a, 3b can be certainly prevented from damage getting into an unrecoverable state.