Abstract: A transaction system having a first transportable integrated circuit (IC) device, a terminal, and a security device is disclosed. The first IC device includes a processor, memory, data stored in the memory, and an operating program stored in the memory. The terminal includes a reader/writer device, a processor, memory, and an operating program stored in the memory. The reader/writer device establishes communication with the first IC device whereby the processor of the first IC device is in communication with the terminal processor. The security device includes a processor, memory, data stored in the memory and an operating program stored in the memory. The security device communicates with the terminal so that the processor of the security device communicates with the terminal processor.

Abstract: A coupler for managing communication between a portable data medium and a data exchange device. The coupler includes bistable control circuitry (25) input-activated by at least two control signals (DTR, RTS) delivered by the data exchange device in one of two first and second predetermined input sequences, and arranged to output at least one power supply signal (VCC) and a data medium reset signal (RST) in a predetermined output sequence, such that the portable data medium is activated only when one specific input sequence of the two input sequences is received.

Abstract: A smart card that includes a descrambler for descrambling entitlement information and data provides improved access control by controlling the manner in which the entitlement information portion of the data stream is passed through the smart card. Entitlement data that is descrambled and used in the smart card for functions such as key generation is reinserted in scrambled form in the high speed output data signal from the smart card. A variable delay device is included in the smart card for controlling when scrambled entitlement data is reinserted into the data stream. Varying the delay permits establishing a desired timing relationship between the reinserted data and other data in the data stream that is output from the smart card. For example, scrambled entitlement data in the output data stream can be made to exhibit substantially the same timing relationship to other data that exists in the input data stream.

Abstract: A method of preventing removal of a smart card having a counter zone associated with a first reference zone, and a balance zone associated with a second reference zone. The counter zone has at least two levels of counters, each having at least two bits. The counter zone is operable in accordance with the abacus principle. The first reference zone has at least one register with at least two bits and is operable to display the proper erasing of the counters. The second reference zone has at least two fields. Bits of a balance are written simultaneously in the balance zone and in the second reference zone. The balance zone and the second reference zone each include one validation bit making it possible to know if the balance is fully written.

Abstract: A smart card for financial transactions that can be programmed to operate using a variety of applications is disclosed. The card includes an interpreter that interfaces the smart card and an automatic teller machine or merchant terminal. The card includes a plurality of application modules each of which contain application programming that can be used by the interpreter to manage the card-to-system interface. At least one of the application modules can be reprogrammed to provide application programming for the interpreter that is compatible with the locally prevalent application program used by automatic teller machines and card terminals in the area where the cardholder is traveling.

Abstract: A point of service (POS) terminal having an integral field replaceable printer for printing a customer receipt and a method for replacing the integral printer are provided. The POS terminal comprises a single, unitary housing which houses the various components typically associated with a POS terminal, but which is also configured to accommodate an integral printer within the terminal housing. The integral print module may be easily accessed, removed and replaced by a merchant without the use of tools or special training and instruction. A moveable access panel associated with the terminal housing provides access to the removable, replaceable printer cartridge and allows the printer cartridge to be removed from the POS terminal and replaced without having to disassemble the POS terminal.

Abstract: A secured network system comprising a readykey controller connected to a st card reader and a power relay switch. The user inserts a microchip embedded card into the first card reader which transmits a first electrical authorization signal to the readykey controller indicating that the user is authorized to use a computer for receiving and processing classified data. The readykey controller then supplies a first enable signal to a power relay switch activating the power relay switch which couples the computer's power supply to an external power source. The secured network system also allows the user to receive and process classified data, by setting a manual A/B switch to a predetermined position which allows a secured network server to be connected to the computer. The user next inserts his proximity card into a second card reader which then transmits a second electrical authorization signal to the readykey controller indicating that the user is authorized to receive and process classified data.

Abstract: A transponder system for monitoring and logging depository transactions in which bags loaded with funds to be deposited in a bank are put, one at a time, into a bank inlet hopper from which the bags drop through a chute into a vault. Incorporated in each bag is a tag in the form of a passive transponder adapted to receive a radio-frequency interrogation signal and to retransmit the signal as a coded signal defining a number identifying the bag. Installed in the vault is a transceiver that transmits the interrogation signal in a confined radiation field within the vault, the field being intercepted only when a tagged bag falls into the vault or is withdrawn from the vault. When the field is intercepted by a tagged bag, its transponder picks up the interrogation signal and transmits to the transceiver the coded signal identifying the bag.

Abstract: A data medium in the form of a check card is known. Such check cards include a memory in which at least one amount of money is stored. If the user wishes to purchase or use a product or service, the amount of money is debited by the vendor. If the vendor intents to defraud the user, or simply makes an unintentional error, too much money may be debited from the data medium without the user noticing immediately that this has occurred. This type of fraud or error may also occur when using other data mediums, including credit cards, debit cards, special purpose cards such as telephone cards and transportation cards, and the like. In order to avoid such fraud or error, further memories are provided in the data medium according to the present invention, wherein one internal memory serves solely for the purpose of accepting amounts of money from outside.

Abstract: A battery-free non-contacting information card of a relatively simple arrangement which prevents an IC chip or the like from being destroyed by an excess voltage. This non-contacting information card includes a resonance circuit (3) for receiving a carrier signal (e.g., FSK signal) modulated on the basis of information supplied from a card reader/writer (2), an information processing systems (5), (6), (7) for obtaining information from the carrier signal and a rectifier systems (13) for obtaining a voltage by rectifying the carrier signal, wherein the non-contacting information card can be operated by the voltage obtained at the output side of the rectifier circuit (13). The resonance circuit (3) includes a variable capacitive element (3d).

Abstract: For a memory card that includes memory blocks containing reliability parameters (P.sub.1, P.sub.2, and P.sub.3) and respective reliability weights (PF.sub.1, PF.sub.2, and PF.sub.3), for the parameters, the method comprises the following steps:determining the reliability weights corresponding to the access request;computing an interactive reliability weight (PFI) as a function of the respective reliability weights of the access request;comparing the interactive reliability weight with an access reliability index (FA); andauthorizing or refusing access to the application as a function of the results of the comparison.

Abstract: An electronic passbook system including an electronic passbook card having two separate account namely a general account and an electronic wallet account, allowing the user to conduct cash deposit and cash withdrawal transactions flexibly, safely and efficiently in both an "on-line" mode and an "off-line" mode. The electronic passbook card has a data memory containing a general account information area for recording information for processing cash deposit and withdrawal transactions in an "on-line" mode, and an electronic wallet account information area for performing mutual transmission with the general account information area in an "on-line" mode and recording information for processing cash withdrawal transactions in an "off-line" mode.

Abstract: A transaction audit system is disclosed comprising a chip card, for completing a transaction between the holder of the chip card and a transaction partner such as a merchant. During the transaction, a transaction identifier is generated uniquely identifying the transaction. For completing execution of the transaction by posting of the payment amount to the merchants account, the chip card transmits a transaction receiver data record comprising the transaction identifier, and further data, if required, to a third party. To allow auditing the transaction settlement posting accuracy, the transaction provider also transmits a transaction provider data record comprising the corresponding transaction identifier to the third party.

Abstract: A smart card having a counter zone associated with a first reference zone, and a balance zone associated with a second reference zone. The counter zone has at least two levels of counters, each having at least two bits. The counter zone is operable in accordance with the abacus principle. The first reference zone has at least one register with at least two bits and is operable to display the proper erasing of the counters. The second reference zone has at least two fields. Bits of a balance are written simultaneously in the balance zone and in the second reference zone. The balance zone and the second reference zone each include one validation bit making it possible to know if the balance is fully written.

Abstract: A paper currency deposit and validating safe includes a generally box like housing having walls forming a chamber comprising a safe for securing money, bill receiving apparatus on the housing for receiving and validating bills of various denominations and for generating a signal proportionate to the denomination of each validated bill, data input port and data output port on the housing, and an electronic cash control system mounted within the safe and including software for recording and storing each deposit into the bill receiving apparatus, each access into the safe and each removal of bills from the bill receiving apparatus and for providing accountings of all such transactions.

Abstract: An input/output device of a smart card according to the present invention comprises a first register having a serial input terminal connected to a terminal serial input/output; a second register having parallel detection terminals, parallel input/output terminals connected to a data bus, and a serial input terminal connected to a serial output terminal of the first register; a third register having a parallel input terminal connected to a ground, a serial input terminal connected to a serial output terminal of the second register, and a serial output terminal connected to the terminal serial input/output; a parity generator which receives parallel output data from the parallel detection terminals of the second register, logically operates upon the parallel output data to generate an operation parity bit which is applied to a parallel input indicator terminal of the first register; and a parity detector which receives a reception parity bit from the first register and the operation parity bit from the parity g

Abstract: A method of writing data to non-volatile memory such as electrically erasable programmable read only memory (EEPROM) in a smart card provides a write status region of EEPROM which is examined on each reset of the card. If the preceding write operation was unsuccessful, perhaps because of deliberate manipulation of the card, a recovery procedure is implemented. If recovery is successful, the card operation can be run. Otherwise the card is unusable.

Abstract: Even when a plurality of cards have entered an communication area, the cards within the communication area may be accessible, and, if a data collision occurs, the order of accessing to the cards is expeditiously determined to perform an efficient communication. Each card determines a timing for returning a response block containing an ID code based on conditions directed by a read/write device and the ID code of its own. The read/write device is caused to receive the response block returned by the contactless IC card and to detect a data collision. Based on this result, the conditions are changed so that a respective response block containing an ID code is returned again, thereby concurrently processing the plurality of contactless IC cards.

Abstract: A host and user transaction system comprising a self contained portable intelligent device (13) for use by a service user, and an interface device (11) for use by a service provider. The intelligent device (13) is in the form of an integrated circuit (IC) card incorporating a single chip microcomputer having an input/output communication port (15), nonvolatile memory (17, 19) and random access memory (21). The interface device (11) has its own memory for storing data and a coupler (14) to connect to the IC card for communicating therewith. The nonvolatile memory (17, 19) has in one part an operating system mask programmed in native code for performing basic functions and in a second part data files with different access restriction levels. The random access memory (21) is available for use by the operating system and stores data received from or ready for transmission via the communication port (15).

Abstract: A battery-free non-contacting information card of a relatively simple arrangement which prevents an IC chip or the like from being destroyed by an excess voltage. This non-contacting information card includes a resonance circuit (3) for receiving a carrier signal (e.g., FSK signal) modulated on the basis of information supplied from a card reader/writer (2), an information processing system (5), (6), (7) for obtaining information from the carrier signal and a rectifier system (13) for obtaining a voltage by rectifying the carrier signal, wherein the non-contacting information card can be operated by the voltage obtained at the output side of the rectifier circuit (13). The resonance circuit (3) includes a variable capacitive element (3d).

Abstract: Process for protecting components of smart cards from fraudulent use, wherein the component is locked as long as an unlock order formed by a secret key has not been applied thereto, characterized in that it consists in writing in the component, at the time of its manufacture, a value and a result, the result being associated with the said value by a given algorithm and the secret key.

Abstract: A hardware device known as a RICH coupler which works between an IC card and its corresponding terminal system. The function of the RICH coupler depends upon its position. Between the card level and the system level there is a third independent level, the coupler. The card level and the system level are involved in the specific card application. The coupler level is application independent. The present invention provides an application independent RICH coupler which works like a supervisor between the applications on the card level and the applications on the system level.

Abstract: An integrated circuit capacitor and method for making the same utilizes a ferroelectric dielectric, such as lead-zirconate-titanate ("PZT"), to produce a high value peripheral capacitor for integration on a common substrate with a ferroelectric memory array also utilizing ferroelectric memory cell capacitors as non-volatile storage elements. The peripheral capacitor is linearly operated in a single direction and may be readily integrated to provide capacitance values on the order of 1-10 nF or more utilizing the same processing steps as are utilized to produce the alternately polarizable memory cell capacitors. The high value peripheral capacitor has application, for example, as a filter capacitor associated with the on-board power supply of a passive radio frequency ("RF") identification ("ID") transponder.

Abstract: A smart card protection system is provided for protecting against unauthorized access of data contents on a smart card through human or electronic-machine tampering. The smart card protection system includes a smart card having an authorized password stored thereon for associated data and a smart card terminal to supply an entered password for accessing the data on the smart card. The smart card includes a comparator to compare the entered password to the stored password, and two counters: a fail counter and a delay counter. The fail counter keeps a fail count indicative of the number of times that the entered password fails to match the stored password. The fail counter is incremented when the entered password fails to match the stored password and decremented when the entered password successfully matches the stored password. The delay counter maintains a delay count that is incremented each time the comparator compares the entered password to the stored password regardless of a match.

Abstract: In a data transmission system, a card reader/writer provided in a terminal device and an IC card are connected through a contact unit, the IC card is started in response to a signal from the terminal device via the card reader/writer, and transmission/reception of data is subsequently performed. In this data transmission system, the IC card has a CPU for outputting a predetermined answer-to-reset data after the IC card is started and controlling at least two protocols, and a memory for storing protocol type information for determining a protocol to be used from the protocols. The control unit is operated upon starting the IC card, renews the protocol type information in outputting the answer-to-reset data, and returns the renewed protocol type information to an initial one in response to transmission/reception of the data.

Abstract: A contact type IC card includes a power supply terminal, a reset terminal and an input/output terminal connected to an external device, an input/output circuit for receiving data from and delivering data to an external device through the input/output terminal, a data processing circuit connected to the input/output circuit for processing data, a memory circuit connected to the data processing circuit for storing data, and an internal reset signal generator for latching a predetermined potential when source power is applied from the external device through the power supply terminal, generating an internal reset signal by using the latched potential to bring the circuits info reset states, and stopping generation of the internal reset signal to release the circuits from reset states when a reset release signal is input from the external device through the reset terminal.

Abstract: A system for open electronic commerce having a customer trusted agent securely communicating with a first money module, and a merchant trusted agent securely communicating with a second money module. Both trusted agents are capable of establishing a first cryptographically secure session, and both money modules are capable of establishing a second cryptographically secure session. The merchant trusted agent transfers electronic merchandise to the customer trusted agent, and the first money module transfers electronic money to the second money module. The money modules inform their trusted agents of the successful completion of payment, and the customer may use the purchased electronic merchandise.

Abstract: The invention relates to chip cards. There is disclosed a chip card (12) with only two contacts intented both to information exchanges (instructions and data) between the card (12) and a card reader and to the power supply of the card (12). According to the invention, the contacts are preferably a clock contact (CLK) used to the synchronization of data and instructions, and a data input/output contact (I/O) used to the transmission of data and instructions from the reader to the card (12) and to the transmission of data from the card (12) to the reader. For the power supply, a full-wave rectifier (bridge of diodes) may be arranged between the two contacts (CLK;I/O). The invention also relates to the communication protocole which allows to use only two contacts (CLK;I/O) while having instructions similar to those of conventional chip cards (initialization of the card, address incrementation of memory cell, reading of the cell, writing, comparison of a confidential code).

Abstract: A method of transmitting data quickly and securely from a smart card during a remote transaction between a fixed station and a mobile item of equipment containing a smart-card reader, said card reader having a fast memory, wherein, on receiving said card, and in addition to storing the data from the card in said fast memory, said reader also stores a pair of data items in said fast memory, one of which data items identifies the number of the card, and the other data item corresponds to an access count indicating the number of accesses to the card, each access by any reader incrementing the access count in the card by unity, and wherein, during the transaction, the mobile item of equipment, which is interrogated remotely by the fixed station, compares said pair of data items stored in said fast memory of said reader with the pair of data items of the card that is currently inserted in the mobile item of equipment, and transmits the result of the comparison and the data of the card, which data is stored in the

Abstract: A file management apparatus capable of inhibiting an accessing operation for a plurality of areas within files. The file management apparatus includes a memory storing files each having multiple areas, a first storage unit for storing lock data denoting a locking condition of an accessing operation for each of the files, a determination device for determining whether the accessing operation for areas to be accessed is inhibited by referring to the lock data for the files, and an accessing device for accessing a particular one of the areas when the determination means determines that access to the group of areas containing that particular area is not inhibited. The file management apparatus also determines the inhibited/non-inhibited status for data areas within each file based on lock data and key data corresponding to each of those data areas.

Abstract: A microcomputer for an IC card arranged so that only a user mode can be performed after the microcomputer has been shipped to a user. Data representing that the microcomputer has been shipped is written at the time of shipment in a test region of an EEPROM. A shipment confirmation routine for confirming whether the shipment data has been written is performed before execution of a branch routine for branching to other programs in accordance with an executed command supplied from outside the microcomputer. If the shipment data has been written in the test region of the EEPROM as confirmed in the shipment confirmation routine, only branching to the user mode is permitted.

Abstract: Smart card payment process.The card in particular contains an irreversible counter, a balance and a certificate proving the integrity of the preceding informations. The content of the card can only be updated by terminals knowing, the calculation secrets of the certificate. By means of the irreversible counter which intervenes in the calculation of the certificate, it is not possible to reload into the card a prior content (balance/certificate), because such a reloading requires the incrementation of the counter, which renders null and void the prior certificate.

Abstract: An IC card system uses a prototype IC card and one or more production IC cards. The prototype card is programmed to execute standard read/write commands, and an initialize command that returns the card to an initial state. The prototype IC card, which can be issued, initialized, and reissued repeatedly, is used for testing purposes during the development of system software. Production IC cards are programmed to execute the standard read/write commands, and a version read command that reads out a version number distinguishing a production IC card from the prototype IC card. Production IC cards are not programmed to execute the initialize command.

Abstract: An integrated circuit card includes packaged semiconductor devices mounted on a substrate. The integrated circuit card also includes a housing bonded by sheet adhesives to the semiconductor devices or substrate. The housing includes top and bottom metal covers and may include spacers positioned between the sheet adhesives and semiconductor devices or substrate.

Abstract: Systems for interchanging information, for example, obtaining cash from a terminal by use of a portable device such as a credit card are well-known but suffer from being vulnerable to fraud. In the invention a highly secure information interchange system is achieved by utilizing an intelligent card as the portable device which verifies that the terminal is a valid one and the terminal in turn verifies that the card is valid. Unauthorized users are screened out by means of a physical characteristic scan of the user such as a fingerprint which is then compared with comparable data stored on the portable device. If an invalid terminal attempts to communicate with the card, the card erases the data and programs from its memory. All programs and data in the terminal are stored in memory which loses its contents when power is interrupted, thus improving the security of the system by making unauthorized use of a terminal very difficult.

Abstract: The method for the management of transactions in a system including card readers and the associated microcircuit cards consists in organizing the memory of the cards, designed for the recording of the transactions, in two zones, one zone that is accessible through the presenting of the bearer code at each transaction, for the transactions involving sums above a predetermined value, the other zone being accessible for the transactions involving sums that are below the predetermined value, without any systematic presenting of the bearer's code: a presenting of the bearer's code commands the writing of opening bits of recording spaces in this second zone until the number of open spaces is equal to N which is a predetermined value. The disclosed method can be applied, notably, to credit cards, telephone cards and multiple-use cards.

Abstract: In a memory area of a data memory in an IC card, data file definition data for defining a data file is stored from one end of the memory area, and a data file is defined from the other end of the memory area. Area definition data for defining an area in a data file is stored from one end of a data file, and an area is defined from the other end of the data file.

Abstract: An improved security system, including a protable smart card and a host computer, eliminates the need for the computer to store individual personal identification (ID) numbers for each user seeking access to the computer. Instead, the computer stores a first encryption algorithm E.sub.1 used in converting a particular identification number (ID).sub.n into a secret code S.sub.n for that particular user. S.sub.n also exists within the memory of the smart card having been loaded into its memory at the time of issue. A challenge number C is generated by the computer and transmitted to the smart card. Within the smart card and the computer, microprocessors respond to the challenge number C, the secret code S.sub.n, and a second encryption algorithm E.sub.2 in order to generate response numbers R.sub.n and R.sub.n ' respectively. Thereafter, R.sub.n is transmitted to the computer where it is compared with R.sub.n '. A favorable comparison is necessary for gaining access to the computer.

Abstract: An IC card has a card body with a plurality of slits extending through the thickness card body and a pair of metallic panels secured to the card body. The metallic panels have engaging portions which extend into the slits when the metallic panels are secured to the card body so that the engaging portions of both panels engage each other within respective slits to fasten both metallic panels to the card body. The electrical potentials of both metallic panels are equalized through these engaging portions.

Abstract: There is provided an IC card comprising a memory within the IC card for storing therein a program operating on a processor included in the IC card and a ROM storing therein a system program for down-leading the program onto the IC card. When a different program is present in the program storage area and a program to be down-loaded into the IC card is to be relocated to a space area, the destination address field of a jump instruction included in the program is altered by a processor included in the IC card.

Abstract: A transaction terminal for use with diverse credit or other transaction cards is provided with an interface unit for receiving a plurality of modules, wherein each module contains programming information corresponding to transactions that may be carried out with at least one of the diverse identification cards presented to the machine. Accordingly, financial institutions who issue cards can independently arrange and program their own security and transaction routines which are to be carried out with the cards and distribute such routines in a secure manner for use on a common terminal.

Abstract: In an IC card having an update function of transaction data, account type, supplementary amount, and valid date are input to the IC card. The IC card adds a renewal number data held therein to the input transaction data, and the data is encrypted using key data, thus generating reference confirmation data. Input confirmation data is generated using the identical encryption generation algorithm by a host system of a credit company. The input confirmation data is supplied to the IC card. A comparison means in the IC card compares the input confirmation data with the generated reference confirmation data. As a result of the comparison, if these data coincide each other, the input data is stored in the memory in the IC card as new transaction data and update processing is executed.

Abstract: An apparatus for issuing a transaction card comprises a value receiving mechanism in the form of a card reader or a bank note acceptor or both. The apparatus includes a memory for storing the exchange rate for a plurality of currencies as compared to a local visitor's voucher which can be issued by the apparatus. A mechanism is also provided for storing a maximum transaction limit corresponding to a selected number of visitor's vouchers, which in turn corresponds to value of currency received. The transaction card is advantageously a smart card or chip card, which carries a program mechanism and central processing unit for manipulating the values which can be stored in the card.

Abstract: A transaction terminal for use with diverse credit or other transaction cards is provided with an interface unit for receiving a plurality of modules, wherein each module contains programming information corresponding to transactions that may be carried out with at least one of the diverse identification cards presented to the machine. Accordingly, financial institutions who issue cards can independently arrange and program their own security and transaction routines which are to be carried out with the cards and distribute such routines in a secure manner for use on a common terminal.

Abstract: An IC card transaction system is disclosed in which at least a portion of the data required to complete a transaction processing is stored in the card by a customer in advance of transaction processing. A skip code is entered for portions of transaction data that is not pre-stored. An automatic transaction processing unit reads the transaction data stored in the card and receives from the customer any additional data which was not previously stored in the card (e.g. data associated with the skip code) and which is required to complete a transaction.

Abstract: A memory card has an outer package comprising a first and a second package section which enclose a semiconductor device. An electrical connector is housed within the front end of the outer package. The front end of each package section overlaps the rear end of the electrical connector so that there are no gaps between the electrical connector and the package sections which could allow dirt or other contaminants to enter the outer package.

Abstract: An identification authenticating system includes a first memory for storing a program to perform a preselected calculation on an input value to obtain an expected result. An input value is supplied to the program wherein calculation is performed thereon. An external signal is supplied, and that signal is compared the expected result. A comparison determines whether the expected result and input value correspond to one another, thereby authenticating an identification.

Abstract: A security file system for a portable data carrier provides improved security for the data carrier and for data contained in files in the data carrier. Although the data carrier may be embodied to look and feel much like an ordinary credit card, it contains a computer and a programmable memory with operating power and input and output data provided through a contactless interface. In order to provide security for the data carrier, the security file system on the data carrier includes a stored access code for verifying the identity of an individual attempting to access the data carrier, and an appropriate routine for limiting the number of unsuccessful attempts to access the data carrier. The security file system is also configurable to include select ones of multiple stored access codes for enabling the retrieval and modification of data in corresponding select ones of the files. The routine similarly limits the number of unsuccessful attempts to access these files.

Abstract: A transaction or authorization card, such as a credit card, check guarantee card or identification card, includes self-contained devices for verifying that the holder of the card is the owner or authorized user of the card. The verification is made by way of the card itself without any peripheral apparatus such as reader. The card contains data input, memory, analyzer and indicator devices which are all built into and contained integrally in the card. The analyzer is capable of determining whether or not input data corresponds to coded data held in the memory. If the input data does correspond to the coded data, a visual indication of such acceptable status is given by the indicator. If the input data does not correspond to the coded data, a visual indication is given that any transaction involving the card by that card holder should be rejected.

Abstract: An IC card system comprises an IC card, each card including a microprocessor, a communication interface, a power supply interface, and memories such as RAM, ROM and EEPROM, and an external device such as a terminal. The terminal functions to supply electric power and send commands to the IC card, and includes a card reader/writer effecting data processing for transactions. The commands include a start command and an end command for the transaction data processing for the IC card connected therewith, and the IC card comprises a validity data flag table within the EEPROM. When a start command is received, the flag table records the validity flag in an invalid state and holds such state as long as an end command is not received.