SMART CARD SYSTEM - what is claimed is: #0035

What is claimed is:

1. A user card transaction system, comprising:

a user card containing a microprocessor and associated memory, and a plurality of contacts for transferring data to and from said microprocessor and memory;

a peripheral device for conducting a transaction in connection with said user card, said peripheral device including a data input/output terminal that is connectable to at least one of the contacts of said user card, for communication with said microprocessor; and which communicates with a data input/output terminal of an other device, and wherein two of the contacts of said user card are respectively connected to the data input/output terminals of said peripheral device and said other device, and said microprocessor selectively provides a data communication path between said two contacts to enable said peripheral device to communicate with only said user card or with said other device; and

an interface device associated with said peripheral device, said interface device providing operation signals to at least some of the contacts of the user card to place said microprocessor in an operational state, including a mode signal which identifies an operating mode in which said microprocessor is to operate to communicate with said peripheral device.

United States Patent 6,199,128 Inventors: Sarat; Jean-Marc (Belmont, CA)