FR2616938A1 - Device for reading an electronic card of the credit card type - Google Patents

Abstract

The read device consists of a case including a connector 6 having terminals which interact with the terminals of the connector of the card when the latter is in the case, a power supply 3, for example of the photovoltaic cell type, and a read and display circuit 11. The read circuit may include function keys T1, T2, T3 which may be keys of a keyboard of an electronic calculator carried by the case. In this case, the keys of the keyboard and the display of the calculator are linked to the read circuit in the card-read position, by means of two routing circuits.

Description

Device for reading an electronic card such as a credit card
The invention relates to the reading of electronic cards used as a means of payment and / or storage.

 There are different types of electronic cards - single memory cards, prepaid, corresponding to a certain number of valuable units, such as those used in telephone booths, - electronic cards, with memory and wired logic, allowing '' charge the cost of a service to an account of the card user; for example cards used for telephoning, from certain booths, the cost of communications being charged to the user's telephone bill. Such cards can only be used with a secret code.

- microprocessor cards, also known as microcircuit cards, or "smart cards", used in particular in electronic banking, and using a secret code as protection. Such cards can be used as a checkbook-type payment method, after loading into the memory an amount credited to the user, the purchases made being debited directly and deducted from said amount. These cards can also be used for many other applications which their extended storage and processing possibilities offer them.

 Generally electronic cards contain non-confidential information and possibly, in the case of the microprocessor card for example, confidential information. In the case of prepaid single memory cards, and in the case of microprocessor cards having in memory a credit of a certain amount, the credit remaining after each use is not confidential information.

 To access this non-confidential information, for example the balance for which the card is credited, or any other data, the user must use a specialized terminal: automatic teller machine, cash dispenser, telephone booth, etc. The electronic card is therefore for the user, a "blind" storage means often requiring additional storage in the form of paper (tickets, receipts, notes taken by the user). The use of electronic cards, in particular credit cards, is becoming widespread, the user must therefore manage the accounts corresponding to the various cards in his possession, and to know at any time the balance of each of them he must keep, for each card, a written record of the last transaction; or the balance if it was given to him during the last transaction.

 The invention aims to allow the reading of non-confidential information from an electronic card using a simple, inexpensive device, compact and that the owner of a card can have permanently on him.

 The subject of the invention is a device for reading and displaying an electronic card, of the credit card type having a connector and an electronic circuit, characterized in that it consists of a case intended to receive the electronic card. , said case comprising a power supply, a read and display circuit connected to the power supply, and a connector connected to the read and display circuit and to the power supply, said connector cooperating with the connector of the electronic card when it is in the case.

 The invention will be better understood with the aid of the description which follows of embodiments illustrated by the appended figures in which - FIG. 1 represents a device for reading the invention, - FIG. 2 represents a variant of the reading device of the invention, - Figure 3 shows another variant of a reading device of the invention, - Figure 4 shows a reading and display circuit of a reading device of the invention , - Figure 5 shows a control circuit of the read and display device of the invention, - Figure 6 shows a simplified variant of the read and display circuit in the case of a memory card, - Figure 7 ~ shows a calculator assembly reading circuit of the device of Figure 3.

 The invention consists of a reading and display device in which the card is inserted for reading, or in which it is stored, without any use.

 Figure 1 shows a reading device of the invention.

In this figure the reading device in the form of a case in which an electronic card 2 is slipped. The case is for example made of relatively rigid plastic and one of the walls is provided with a power supply 3, a reading and display circuit 4 comprising a display 5, and a connector 6. The connector is on the inside of the case so as to establish contacts with the connector of the electronic card 2 when the latter is slid into the case, the card connector being for example of the type used for credit cards. The connector 6 of the reading device consists for example of metal strips coming into contact with the connector of the card.

 The power supply 3 is for example a photovoltaic cell, a battery, or even an accumulator, the thickness of the wall of the case not being limited like that of the electronic cards and can consequently have a greater thickness for housing a battery, or an accumulator, flat, of the button type for example.

 FIG. 2 represents a variant of the reading device of the invention. In this figure, the reading device 10 also has the form of a case in which an electronic card 2 is slipped. The case is, as in FIG. 1, for example made of relatively rigid plastic, and one of the walls is provided with a power supply 3, with a reading and display circuit it comprising a display 5, and a connector 6 located on the inside of the case, this connector consisting of metal strips coming into contact with the connector of the electronic card.

As in FIG. 1, the power supply 3 can be a photovoltaic cell, a battery or an accumulator of the button type. The read and display circuit 11 differs from the read and display circuit 4 in FIG. 1 in that it includes function keys such as T1, T2, T3. Circuit 4 can be used with memory cards and with microprocessor cards, while circuit 11 can only be used with microprocessor cards. In the case of a power supply 3 consisting of a battery or an accumulator , the reading and display circuit of FIGS. 1 and 2 comprises an on / off button To, which is for example of the sensitive button type, in order to avoid permanently supplying the reading and display circuit and the electronic card when it is in the case, which would unnecessarily shorten the life of the battery; such an on / off button is not necessary in the case of a photovoltaic cell.

 FIG. 3 represents another variant of the reading device of the invention. In this figure, the reading device is a case 27, one of the walls of which comprises a connector 6, a reading circuit and a calculator having: a keyboard 30, a power supply 3 and a display 11. The power supply 3 also powers the read circuit, and the display 11 also serves to display the data of the card 2, this data being of course non-confidential, as in the case of FIGS. 1 and 2; the power supply 3 can be a photovoltaic cell, a battery or an accumulator of the button type.

 In FIGS. 1 and 2, the photovoltaic cell 3, and the reading and display circuit 4 or 11 constitute a hybrid circuit which is inserted in the wall of the case carrying the connector 6 in FIG. 3. the calculator and reading circuit assembly which constitutes a hybrid circuit. The photovoltaic cell has a surface of two to four square centimeters and delivers a power of ten to twenty microwatts under one hundred lux of illumination, with a conventional photovoltaic conversion efficiency of the order of 5% (100 lux represents the minimum of lighting required for reading, the comfortable level being around 200 lux).

 The LCD-type display consumes a few microwatts for eight digits displayed in seven segments, and the consumption of the electronic circuit of the reading and display device being of the same order, the power delivered by the photovoltaic cell is sufficient to ensure the operation in all conditions.

 Furthermore, the use of thin layers makes it possible to easily produce photovoltaic cells by choosing the current-voltage distribution, at given power, offering the possibility of adapting the photovoltaic cell to the supply voltage of the electronic circuit 8 of the card and of the display.

 In dimensional terms, the whole photovoltaic cell - reading and display device will represent an area of the order of 5 to 10 square centimeters, not posing any problem of installation on such a device.

 The addition of one or more keys can be carried out on the hybrid circuit using the technology of sensitive keys also allowing thicknesses of a few tenths of a millimeter.

 FIG. 4 represents the read and display circuit 11 of FIG. A. In this figure, 8 is the electronic circuit of a microprocessor card, and B1 to B8 are the terminals of the connector of the card, the connector being assumed to be of the type commonly used for such cards; the terminals are connected to the electronic circuit 8. B1 and B2 are terminals generally not used in credit cards and available for particular applications; terminal B3 is a ground terminal, terminal B4 is a clock terminal, terminal B5 is an initialization terminal, terminal B6 is a data input / output terminal in series, terminal B7 is a terminal d write power supply, connected in use to a write voltage of for example 21 volts, and the terminal B8 is a power supply terminal of the electronic circuit 8, connected in use to a voltage of for example 5 volts.

The reading and display circuit 11 is connected to the power supply 3 of the reading device by a supply wire FA. When the power supply 3 is a photovoltaic cell the power wire 3 is connected directly to the power supply 3; 'when this power supply is a battery or an accumulator, the power wire FA is connected to the power supply by the key stop / start To. The read and display circuit comprises a control circuit 12, a buffer memory 13 and the display 5 which is of the digital or alphanumeric type, and the connector 6 of the case comprises the terminals C7 to C5 which cooperate with the terminals B4, BS, B8, B6, B3, respectively. The terminals C7 and C2 are connected to a clock output H and to a signal output S1 of the control circuit 12, connected to the supply wire FA, and having inputs El, E2, E3 connected to function keys T1, T2,
T3, themselves connected to the power supply wire FA. The supply terminal C3 is connected to the supply wire FA. Terminal C4 is a data terminal connected to a data input of the buffer memory 13, connected to the power supply wire FA and having a clock input connected to the clock output H by a wire 23 and an initialization input connected to the signal output S1 by a wire 24; the buffer memory 13 is connected by a parallel link constituted by n wires F1 to Fn to the display 5. The terminal C5 is a ground terminal.

 The reading and display circuit can of course include a number of function keys other than three; if it does not include a function key, it then corresponds to the reading and display circuit 4 of FIG. 1 which illustrates the simplest case or only one item of data is to be displayed, for example credit card balance payment, or the remaining credit from a phone card.

 If you wish to display several non-confidential data stored in the card, such as, for example, credit balance, last transaction made, number of purchases made during a given period of time, sum of these purchases, etc., use the function keys of the reading and display circuit of FIG. 4, said function keys allowing the user to display a data item, or to scroll through different data items.

The electronic card-case assembly constitutes a complete functional entity, perfectly autonomous in energy, and in addition the rigid case, of reduced bulk, ensures the protection of the card, its electronic circuit and its connector. When the photovoltaic cell is lit, or when the On / Off key To is pressed in the case of a battery supply, the control circuit 12, the buffer memory 13, the display 11 and the electronic circuit 8 from the powered output card. The control circuit 12 delivers to the electronic circuit 8 and to the buffer memory 13 an initialization signal and a clock signal which will synchronize their exchange of information; the buffer memory 13 being reset to zero by the initialization signal is therefore ready to receive data which is stored in the buffer memory and displayed on the display 5. All of these operations take place in a very short time no noticeable by the user.

 So that the insertion of the card in the case also initializes the display sequence, the wall of the case opposite to that carrying the connector may have, on its inner face, a metal part facing the connector so as to short -circuit the power supply via terminals C3 and C5 of the connector (C5 ground terminal and C3 power terminal) when the card is not in the case, in the case where the power supply is a cell photovoltaic. This short-circuiting of the supply exploits a particular characteristic of the photovoltaic cells which can operate indifferently in open-circuit, in short-circuit or even on any impedance. Inserting the card into the case eliminates the short circuit and brings up the supply voltage, if the photovoltaic cell is exposed to light.

We are therefore brought back to the case where, the card being stored in the case, the user takes the case out of its storage and exposes it to light, the control circuit then being supplied delivers the initialization signal.

 This short-circuiting of the power supply when the card is not in the case also makes it possible to prevent the buffer memory 13 of the reading and display circuit then taking an indeterminate state causing a random display. in this way the display only works when the card is in place in the case, and the latter is exposed to light.

 The function keys, when they exist, make it possible, via the control circuit, to instruct the microprocessor of a card to deliver other data, and even allow the user to communicate with the microprocessor, the replay device of the invention then serving as a sort of simplified, portable terminal.

 FIG. 5 represents the control circuit of FIG. 4.

The control circuit comprises a clock 20, pulse generators Go, G1, G2, G3, an OU21 gate and a power detection circuit 22. The clock 20, the power detection circuit 22 and the generator Go are connected to the supply wire FA, itself connected to the photovoltaic cell 3 of FIG. 4. The output H of the clock is connected to the pulse generators Go,
G1, G2, G3, at terminal C1 and by wire 23 to buffer memory 13 of FIG. 4. The power detection circuit 22 is connected at output to an authorization input for clock 20 and the pulse generator Go; it delivers an authorization signal when the level of the supply voltage delivered by the photovoltaic cell exceeds a threshold value. The inputs El, E2, E3 of the pulse generators G1, G2, G3 are connected to the supply wire. FA by the function keys T1, T2, T3. The gate OU21 is connected as an input to the output of the pulse generators Go, G1, G2, G3, and its output S1 is connected to the terminal C2 and by the wire 24 to the buffer memory 13. The pulse generators deliver each one train of pulses, the number of pulses of each train being different; for example the generator Go delivers a pulse when it receives the authorization signal from the supply detection circuit 22, and the generators G1, G2, G3 respectively deliver two, three, four, pulses when the associated function key T1 , T2, T3 is pressed.

The pulse delivered by the generator Go constitutes the initialization signal; the pulse trains delivered by the generators G7, G2, G3 characterize the corresponding function, therefore the data to be displayed. If the reading and display device does not include a function key, the generators G7, G2,
G3, and the gate OUZ1 do not exist; the generator Go is directly connected to the terminal C2, and the initialization signal delivered by the generator Go authorizes the output of the data to be displayed.

 In the case of an electronic memory card, without microprocessor, the reading and display circuit of the reading and display device can be simplified if the data stored in the memory of the card is delivered in parallel form.

 FIG. 6 represents such a simplified reading and display circuit. In this figure, the power supply 3 is, as before, a photovoltaic cell, or a battery or even an accumulator.

 Reference 14 designates the electronic circuit of the card and it has been assumed that the data were routed by a parallel bus constituted by n wires, f1 to fn, connected to terminals BS1 to BSn of a connector of the card; the electronic circuit 14 is also connected to a power supply terminal BE7, and to a ground terminal BE2.

The connector of the card therefore includes the terminals BE7, BE2 and BS7 to BSn; it is therefore different from the connector usually fitted to credit cards.

 The reading and display circuit consists of the display 5, which is connected by the supply wire FA to the supply 3 either directly if the latter is a photovoltaic cell, or by means of a On / Off button To if it is a battery or an accumulator.

 The supply device comprises terminals CE7, CE2 and CS1 to CSn which cooperate with the terminals BE7, BE2 and BS1 to BSn, respectively. The CE7 terminal is a power supply terminal connected to the power supply 3 either directly if the latter is a photovoltaic cell, or by the on / off key To if it is a battery or an accumulator; terminal CE2 is a ground terminal; the terminals CSî to CSn are connected to the display 5.

 The case of an electronic card can also include an electronic calculator of the well-known pocket calculator type. Under these conditions a reading circuit is integrated in the calculator, the power supply and the display then being common to the calculator and to said reading circuit.

- Figure 7 schematically shows a read and display circuit 28, a calculator 29 and a power supply 3 connected at the output by a supply wire FA to the calculator and to the read and display circuit. The calculator comprises a keyboard 30, a calculation circuit 31 and a display 5. The reading circuit 28 comprises a control circuit 32, a code memory 33, a timing circuit 34, an OR gate 35, an interface circuit 36, a buffer memory 13 and two switching circuits 37 and 38, of the electronic type.

 The keyboard 30 of the calculator has an output connected by a link L7 at the input of the calculation circuit 31 and by a link L2 to a common terminal of the first switching circuit 37; the link L2 is made up of ten wires each corresponding to a numeric key on the keyboard and one or more other wires of keys other than the numeric keys used as function keys to control the control circuit 32; the L7 link is made up of wires connected to the keyboard keys not connected to the L2 link.

The calculation circuit 31 is also connected at the input to a link L3 itself connected to a terminal of the first switching circuit 37; this L3 link has as many wires as the L2 link. The calculation circuit 31 is connected at the output by a link L4 to a terminal of the second switching circuit 38, a common terminal of which is connected at the input of the display 5 by a link L5 having as many wires as the link L4. For calculator operation, the first and second switching circuits connect the link L2 to the link L3 and the link L4 to the link L5.

 In the reading and display circuit 28, the first switching circuit 37 has another terminal connected by a link L having as many wires as the link L2, at the input of the gate OR 35 a function link LF, having one wire per function, connects said control circuit to the wires of the link L corresponding to the keys of the keyboard used for these functions, for example the keys corresponding to the four operations: division, multiplication, subtraction, addition; a code link LC consisting of ten wires, connects the input of the code memory 33 to said wires of the link L corresponding to the numeric keys of the keyboard. These ten wires are necessary to enable the secret code to be sent to the electronic card as will be explained below.

 The control circuit 32 has a clock output H connected directly to a terminal C1 and to the buffer memory 13 by a wire 23, and a signal output Sî directly connected to a terminal C2 and to the buffer memory by a wire 24; the control circuit also has an authorization input connected, by an authorization wire 40 in series with a key code TC, to the supply wire FA itself connected to a terminal C3.

The control circuit 32 is for example that of FIG. 5 in which the function keys T7, T2, T3 are keys on the keyboard, and in which the supply detection circuit 2 is connected to an input of a AND gate of which another input is connected to wire 40, the output of the AND gate being connected to the authorization input of the clock 20 and of the first pulse generator G
The code memory 33 has an authorization input connected to the supply wire FA by said code key TC, and an output connected to an input of the interface circuit 36.

 The timing circuit 34 has a control input connected by an electronic card key TC1 to the power wire FA, another control input connected by a calculator key TC2 to the power wire FA, and yet another input connected to the output from OR gate 35; at output, the timing circuit 34 is connected to a switching control input of the first and second switching circuits 37 and 38.

 The interface circuit 36 is connected at output to a terminal C4, and has another input connected to a data input of the buffer memory 13.

 The buffer memory 13 is connected at the output to a terminal of the second routing circuit 38 by a data link LD.

 A terminal C5 of the read and display circuit is connected to ground.

 The terminals Cl, C2, C3, -C4, CS cooperate with the connector of the electronic card when the latter is in place in the case.

 Although the code keys TC, electronic card TC1, and calculator TC2 are represented in the reading and display circuit 28, it is understood that they are part of the keyboard which can also include other keys than those represented. The connections of the TC code keys, TC1 electronic card and TC2 calculator with the control circuit 32, the code memory 33 and the timing circuit 34 are made directly, without going through the first routing circuit 37 '; they are of course directly connected to the power supply 3.

 To use the calculator in its normal calculation function, the user presses the calculator key TC2 and the delay circuit 34 delivers a switch control signal to the switch circuits 37 and 38 which then ensure the switch of the link L2 to link L3 and link L4 to link L5 he can then use the keyboard normally, the results of the operations carried out being displayed on display 5.

 Operation in a calculator is independent of the presence or absence of the electronic card in the case.

 For a reading of the electronic card, present in the case, the user presses the electronic card key TC1 and the timing circuit delivers a switch control signal to the switch circuits 37 and 38 which then ensure the switching from the L2 link to the L link and from the LD data link to the L5 link; he then presses the code key TC to deliver an authorization signal to the memory code 36 and to the control circuit, and composes his code using the numeric keys of the keyboard if the electronic card is a microprocessor card each digit is temporarily stored in the code memory to be transmitted to the electronic card via the interface circuit 36 which provides the input / output link with said electronic card. The code memory only keeps the secret code for a very short time, corresponding at a time delay of for example a few milliseconds, necessary for the transmission of the code to the card; when the time delay has elapsed, the code memory is automatically reset to zero so as to prevent the secret code from being accessible outside the card itself. After recognition of the code by the card, the card can receive user commands via the function keys on the keyboard.

If the electronic card is not a microprocessor card, the user, after pressing the code key TC which allows him to issue an authorization signal to the control circuit 32, sends a read command by a function key of the keyboard.

 The timer circuit 34 having a timer input connected via the OR gate 35 to the wires of the link L connected by the first switching circuit 37 and the link L1 to the numeric keys and to the function keys of the keyboard, any action on one of these keys starts the delay.

 At the end of a certain time without action on the keys of the keyboard (from a few seconds to a few tens of seconds for example) the delay circuit 34 delivers a switch control signal which puts the switch circuits 37 and 38 into calculator position, connecting link L2 to link L3 and link L4 to link L5. However, the user can switch to calculator operation without waiting for the end of the time delay; for this it suffices to press the calculator key TC2, this action canceling the delay so that the delay circuit delivers a switch control signal to the switch circuits 37 and 38.

 In the case of electronic microprocessor cards, the extended possibilities of microprocessors make it possible to envisage the possibility of using them to store data, in addition to their banking function.

 The use of a case with keyboard, of the type shown in FIGS. 3 and 7, the keyboard possibly being of the alphanumeric type, as well as the display, can allow the writing of data in the card; the case then becomes a complete portable terminal. To allow writing and as shown in FIG. 7, the power supply must deliver, a writing voltage to a writing terminal C6 for this purpose the power supply and the writing terminal are connected by a wire FE.

 The reading device of the invention may include, in place of the calculator, devices of equivalent size, possibly having a display, powered by the power supply 3, such as: quartz watch, travel alarm clock, electronic game , radio receiver, etc. In this case the circuit for reading and displaying the electronic card is then of the type shown in FIG. 4.

The reading and display circuit of FIG. 7 can of course be simplified in the case of a case for reading an electronic card with microprocessor, but without using the code; in this case the code memory 33, the interface circuit 36 and the code key TC do not exist, and the control circuit 32 is initialized by the power supply, that is to say, in the case of a cell photovoltaic, as soon as it is exposed to light, of course the writing terminal C6 does not exist and the connections
L2 and L have a number of wires limited to the number of function keys.

 The shape of the reading and display device of the invention is not limited to those shown in FIGS. 1, 2 and 3, which are given only by way of example, and the case may on the contrary appear. in different forms without departing from the scope of the invention. Thus the case can be in the well-known form of a card holder, of the wallet type, having several compartments in which the cards are stored. In such a case, a compartment is assigned to the reading of the cards and comprises this effect a power supply, a read and display circuit and a connector; such a case generally having a flap which covers the compartments, the power supply, of the photovoltaic cell type, and the display can be placed on said flap and be connected by flexible connections, well known, to the reading circuit and to the connector arranged , them, on a compartment. In the case where the reading and display device of the invention comprises a calculator, the latter, the power supply, the reading and display circuit and the display can be arranged on the flap of the card holder and be connected by flexible connections to the connector arranged on a compartment. A case can be in different forms, the name case is not limited to the forms shown, but on the contrary applies to all variants.

Claims (11)

1 / Device for reading and displaying an electronic card, of the credit card type having a connector and an electronic circuit, characterized in that it consists of a case (1) intended to receive the electronic card (2 ), said case comprising a power supply (3), a read and display circuit (4) connected to the power supply, and a connector (6) connected to the read and display circuit and to the power supply, said connector (6) cooperating with the connector of the electronic card when the latter is in the case. 2 / Reading and display device according to claim 1, characterized in that the power supply (3) is a photovoltaic cell. 3 / Device according to claim 1, characterized in that the power supply (3) is a battery and that the case comprises an on / off button (To) to connect the battery to the reading and display circuit and to the connector. 4 / Device according to claim 1, characterized in that the connector (6) of the case comprises a first (C1), a second (C2), a third (C3), a fourth (C4), and a fifth (C5) terminals, which cooperate respectively with a clock terminal, an initialization terminal, a power supply terminal, a data input / output terminal and a ground terminal of the connector of the electronic card, that the circuit of reading and display (4) comprises - a control circuit (12) connected to the power supply (3) and having a clock output (H) connected to the first terminal (C1) of the connector (6 ?, and an output signal (S1) connected to the second terminal (C2) of the connector, - a buffer memory (13) connected to the power supply, and having a clock input and an initialization input connected respectively to the clock output (H) and the signal output (S1) from the control circuit (12), and a given input connected to the fourth terminal (C4) of the connector, - a display (5) connected to the output of the buffer memory (13) and of the power supply, - and that the third and fifth terminals (C3, C5) of the connector are connected respectively to the power supply (3) and to the ground. 5 / Device according to claim 4, characterized in that the reading and display circuit further comprises function keys (T7, T2, T3) for selecting data to be displayed, said keys being connected by a - part to the power supply (3) and secondly to a respective input of the control circuit (12). 6 / Device according to claim 4, characterized in that the control circuit (12) comprises: a clock (20) connected to the power supply and having a clock output (H) connected to the first terminal (C7) of the connector , and to the buffer memory (13), a first pulse generator (Go) connected to the power supply (3) and having a clock input connected to the clock output (H) of the clock (20), and a signal output connected to the second terminal (C2) of the connector and to the buffer memory, and a power detection circuit (22) connected to the power supply and having an output connected to the clock input (20) and at the input of the first generator (Go) to which it delivers an authorization signal when the supply voltage reaches a threshold. 7 / Device according to claim 5, characterized in that the control circuit (12) comprises a clock (20) connected to the power supply and having a clock output (H) connected to the first terminal (C1) of the connector, and to the buffer memory (13), a first pulse generator (Go) connected to the power supply (3) and having a clock input connected to the clock output (H) of the clock (20), a power supply detection circuit (22) connected to the power supply and having an output connected to the clock input (20) and to the input of the first generator (Go) to which it delivers an authorization signal when the voltage of power supply reaches a threshold, a pulse generator (Gî, G2, G3) per function key (T7, T2, T3), each generator being connected to the power supply by a function key, and having a clock input connected to the clock output (H) of the clock (20), and an OR gate (21) connected as an input to the first pulse generator and to each of the generators connected to a function key, and having a signal output connected to the second terminal (C2) of the connector and to the buffer memory. 8 / Device according to claim 1, characterized in that it further comprises a calculator (29) having a keyboard (30) having ten numeric keys and different keys for calculation operations, a calculation circuit (31) and a display (S>, said calculator being connected to the power supply, that the reading and display circuit is connected to a first switching circuit (37) connecting keyboard keys to the calculation circuit for calculator operation or to the reading and display circuit for operation in reading an electronic card, and to a second switching circuit (38) connecting the display (5) to the calculation circuit (31) for operation in a calculator or in the reading and display circuit for operation in electronic card reading, said keyboard keys connected to the reading and display circuit by the first switching circuit being on the one hand the ten numeric keys for dialing a cod e secret and, on the other hand, keys among the keys used for the calculation operations, for selecting in card reading operation, data to be displayed. 9 / Device according to claim 8, characterized in that the connector (6) of the case comprises, a first (ass) a second (C2), a third (C3), a fourth (C4) and a fifth ( C5) terminals which cooperate respectively with a clock terminal, an initialization terminal, a power supply terminal, a data input / output terminal and a ground terminal of the connector of the electronic card, - that the reading circuit and display comprises a control circuit (32) connected to the power supply, and having a clock output (H) connected to the first terminal (cul) of the connector, and a signal output (S1) connected to the second terminal ( C2) of the connector, and an input connected to the first switching circuit (37), a code memory (33) connected at the input to the first switching circuit (37) and at the output to an interface circuit (36), a buffer memory (13) connected to the power supply and having a clock input and an initialization input connected respectively to the ho output clock (H) and at the signal output (S1) of the control circuit (32), a data input connected at the output of the interface circuit (36) itself connected to the fourth terminal (C4) of the connector, and a data output connected in the second routing circuit (38), a code key (TC) connected on the one hand to the power supply and on the other to an authorization input of the control circuit and of the code memory, and a timing circuit (34) having a first control input connected to the power supply by an electronic card key (TC1) and a second control input connected to the power supply by a calculator key (TC2), a timer input connected by an OR gate (35) to the first switching circuit, and an output connected to a control input of each of the first and second switching circuits. 10 / Device according to claim 9, characterized in that the connector (6) of the case also includes a sixth terminal (C6) connected to the supply from which it receives a write voltage, said sixth terminal cooperating with a writing terminal of the connector of the electronic card. 11 / Apparatus according to claim 1, characterized in that the electronic card comprises a parallel type memory receiving and delivering data by n wires connected to n data terminals of the connector of the electronic card, as the reading circuit and d display consists of a display (S>, connected to the power supply and that the case connector has a first good (CE1) connected to the power supply and a second terminal (CE2) connected to ground, and n data input terminals (CS1 to CSn) each connected to the display, the first and second connector terminals cooperating with a power supply terminal and a ground terminal of the card connector, and the n input terminals / output cooperating with the n data terminals of the card connector.