Method for selecting an operating mode of a smart card, uses coding of standard electrical signals passed between card and card reader to determine the card operating mode

摘要

The operating mode is selected using one of the supply voltage (VCC), clock signal (CLK) or reset signal (RST). The reset signal is preferred. The selection can operate with either contact type or non-contact cards. Internal testing of the supply voltage determines whether the card is in a contact or non-contact environment. Sampling of the reset signal determines the operating mode.