IC CARD DEVICE

摘要

PURPOSE:To prepare the conditions of communication in a short time and at the same time to supply a clock of a correct frequency to an IC card from the beginning by using a condition setting terminal of the IC card to set the conditions of communication. CONSTITUTION:An IC card 1 contains six communication terminals 3 and two condition setting terminals 4 applying the spare terminals. The terminals 4 are connected to a condition setting means 5 of a reader/writer 2 and set the conditions of communication to the card 1. The reader/writer 2 turns on a power supply of the card 1 and detects the voltage levels of terminals 4 of the card 1 via the means 5. Thereafter the communication is carried out with the card 1 via the terminals 3 and a communication executing means 6 to which the conditions of communication are correctly set. Thus a clock of a correct frequency can be sent to the card 1 from the beginning even with use of IC cards of different clock frequencies.