A smart card pinout

Below are the smart card pinout and description

VCC : Power supply input

RST : Either used itself (reset signal supplied from the interface device) or in combination with an internal reset control circuit (optional use by the card). If internal reset is implemented, the voltage supply on Vcc is mandatory

CLK : Clocking or timing signal (optional use by the card).

GND : Ground (reference voltage)

VPP : Programming voltage input (deprecated / optional use by the card)

I/O : Input or Output for serial data to the integrated circuit inside the card.

Source:

http://en.wikipedia.org/wiki/Smart_card