The GCI681 is a compact, modular device designed for OEM products. The
coupler serves as an interface between the application and a Mifare®
contactless card (GemEasy8000, GemEasy300,
MA8000, GemCombi™/Gate).
The GCI681 has been designed for direct connection to a microprocessor via
the parallel bus. This type of interfacing ensures high communication speeds with the host
equipment, and is thus particularly well suited for contactless card applications
which require very high transaction speeds. The implementation of this device generally
requires the design of a new or modified microprocessor board for the host equipment This
microprocessor board can then serve as a input/output controller, validator or
access-control terminal depending on the application.
High-Speed and Secure Interface
The GCI681 has a built-in interface ASIC as well as a Radio-Frequency (RF)
module.
While handling communication micro-sequences, the interface ASIC translates the
incoming data flow coming from the microprocessor bus into a coded serial signal for use
in the RF module. The ASIC uses a hard-wired algorithm and a random number generator,
offering particularly strong security level: mutual active authentication and stream
ciphering. Using these basic elements, a security scheme can be tailored to the needs of
the specific application. Anticollision management ensures correct handling when there are
several cards in the communication field.
The RF module generates a 13.56 MHz signal over the antenna to the card, thus
transmitting power and the clock signal. Data transmission to the card is achieved using
amplitude modulation on the carrier. Transmission from the card to the coupler is achieved
by means of load modulation.
The RF circuitry is designed to comply with EMC rules (the GCI681 is "CE"
marked) and ETSI 300-330 when used with a Gemplus CGA680 antenna.
The GCI681-BAT has a battery soldered onto the circuit board to safeguard the secret
keys when the power supply is cut off.
