JPH0276192A - Ic card reader - Google Patents

Abstract

PURPOSE:To beforehand prevent the runaway of a CPU by inputting an interrupting signal due to the software into a central processing unit (CPU) when an IC card is removed from a connector. CONSTITUTION:Since an electrode 13-3 for detecting a card is first separated from an electrode in a connector part 1 at the time of removing an IC card, when an address signal, a data signal and a command signal transmitted by a signal electrode 13-4 is effective, the difference between a card detecting latch signal (b) and a card detecting signal (a) due to a comparator 3 is detected. An interrupting selector signal (c) is active, hardware interruption is applied to a CPU 7 and simultaneously, the signal (c) is also inputted to a selector circuit 4. Then, the selector circuit 4 selects a main data bus (f) and the software interrupting code is read from a fixed data output machine 6, the software interruption is applied and the processing of the interruption routine is executed. Thus, the runaway of the CPU 7 is prevented beforehand.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an IC card having an active element on a substrate and an IC card reader for exchanging data with the IC card.

2. Description of the Related Art In recent years, IC cards in which active elements are provided on resin substrates have come to be used as data storage cards in many fields, similar to magnetic cards. The IC card reader that inputs and outputs data to and from this IC card is
There are two types: one type that inputs and outputs data by loading the card into the main body of the device, and the other type that inputs and outputs data by inserting only a portion of the IC card into the main body of the device. Regarding this IC card, special public
Publication No. 91, USP No. 4,417,413, and patent application publication number 55-500138 for IC card readers.
The prior art is disclosed in the above publication.

Problems to be Solved by the Invention By the way, it has been possible to insert or remove an IC card at any time after turning on the power to an IC card reader, but this is possible with an IC card that simply stores a data file.
If a program is stored on an IC card, it is prohibited to remove the IC card while the program is being executed, and the only way to prevent this is to write it down in the operating manual or on the IC card to alert the operator. It wasn't.

Therefore, if the operator accidentally removes the IC card while the program is running, the code FFh (h indicates hexadecimal) is input to the IC card reader's CPU.
Your system may go out of control, your created files may become corrupted, or your data may be lost.

The present invention has been made in view of the above problems, and it is an object of the present invention to prevent the system from running out of control and data and files from being damaged even if the IC card is removed during program execution after system startup.

Means for Solving the Problems In order to solve the above conventional problems, the IC card reader of the present invention has a CPU, a power electrode provided on the IC card, and a power supply electrode for transmitting address signals, data signals, and command signals. a connector section having a plurality of electrodes connected to the electrodes of the connector section; and when the IC card is removed from the connector section, the power supply electrodes and electrodes for transmitting address signals, data signals, and command signals are connected to the connector section. a first means for generating a specific signal prior to leaving the electrode;
The apparatus includes software interrupt signal generating means for generating a software interrupt signal to the CPU, and second means for outputting a software interrupt signal to the CPU based on the output from the signal generating means.

Function When removing the IC card from the connector, use the code FF.
A software interrupt signal is input before h is input to the CPU, and runaway of the CPU is prevented.

Example Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an IC card reader. In the figure, 1 is a connector portion into which an IC card can be inserted, and is provided with one or more IC card connectors. a is an IC inserted into and removed from the connector section 1;
A card detection signal output from the card, 2 a latch circuit that holds the state of the card detection signal a, b a card detection latch signal output from the latch circuit 2, 3 the card detection signal a and the card detection latch C is an interrupt selector signal outputted from the comparator 3, and 4 is data for transmitting a software interrupt code outputted from the fixed data output device 6 by the interrupt selector signal C. A selector circuit that switches between the bus d, the data bus e connected to the connector section 1 and the peripheral memory 5, f a main data bus connecting the central control unit (hereinafter referred to as CPU) 7 and the selector circuit 4, and g an output from the CPU 7. and h is a clear signal that disables the interrupt selector signal C, which is the output signal of the comparator 3, and h is the CPU
A trigger signal is outputted from 7 to trigger the latch circuit 2, 8 is a display device that displays information such as messages under the control of the CPU 7, and 9 is a pull-up resistor for setting the card detection signal to a high level. It is.

FIG. 2 is a plan view of an IC card according to an embodiment of the present invention. In the figure, reference numeral 11 indicates an IC card body, on which an active element 12 and a plurality of electrodes 13 are provided. ing. The electrodes 13-1 and 13-2 are connected to the electrodes of the IC card so that when the IC card is inserted into the connector of the IC card reader described above, they are first connected to the electrodes inside the connector. These are the power supply electrode and the ground electrode formed at the position closest to the end face on the insertion side into the reader. 13-3 is the electrode on the side where the IC card is inserted into the IC card reader among the plurality of electrodes so that when this TC card is inserted into the connector of the IC card reader mentioned above, it will be connected to the electrode in the connector last. This is the card detection electrode formed at the farthest position from the end surface. 13-4 is the power supply electrode 13-1
The ground electrode 13-2 is formed at a position farther from the end face on the side to be inserted into the IC card reader, and at a position closer to the end face on the side to be inserted into the IC card reader than the card detection electrode 13-3. It is a signal electrode for transmitting data signals and command signals.

The specific operations of the IC card reader and IC card of this embodiment configured as described above will be explained with reference to the flowchart shown in FIG.

First, in step (a), the power is turned on and the entire system starts up, and the CPU 7 detects this and enables the clear signal g to clear the interrupt selector signal C (step (b)). Then step (C
), the trigger signal is outputted, and the latch circuit 2 captures the card detection signal a indicating the current insertion state of the IC card and holds that state. In this state, that is, immediately after the power is turned on, the card detection signal a and the card detection latch signal are the same, so the CPU 7 does not activate the interrupt selector signal C.

Next, when the IC card having the above-mentioned configuration is inserted into the connector section 1, first the power supply electrode 13-1 and the ground electrode 13-2 are connected to each other.
contacts the electrode inside the connector, and power is supplied from the IC card reader to the IC card. Subsequently, the signal electrode 13-4 for transmitting address signals, data signals, and command signals comes into contact with the electrode inside the connector, and finally the card detection electrode 13-3 comes into contact with the electrode inside the connector. Become. Here, the card detection signal a, which was at a high level due to the action of the pull-up resistor 9 before the IC card was inserted, is activated when the card detection electrode 13-3 contacts the electrode in the connector and Since it is connected to ground through the circuit, it changes to low level.

Therefore, there is a difference between the card detection latch signal from the latch circuit 2 inputted to the comparator 3 and the card detection signal a, and the process moves from step (d) to step (e). The interrupt selector signal C, which is the output from the interrupt selector signal C, becomes active. This interrupt selector signal then issues a hardware interrupt to the CPU. At the same time, the interrupt selector signal C is also input to the selector circuit 4. Then, the selector circuit 4 switched from selecting the data bus e to selecting the main data bus f, and the CPU 7 read the software interrupt code from the fixed data output device 6 via the selector circuit 4. Occasionally a software interrupt occurs. Then, in step (f), the interrupt routine processing is executed. Note that this software interrupt code is rCCh (where h indicates a hexadecimal number) when Intel's 16-bit CPU 8086 is used as the CPU.

Thereafter, the CPU 7 enables the clear signal g and the trigger signal. Then, data indicating that the IC card has been inserted is held in the latch circuit 2.

Furthermore, when the IC card is undulating, the card detection electrode 13-3 first separates from the electrode in the connector section 1, so that the address signal, data signal, and command signal transmitted by the signal electrode 13-4 are effective. At a certain point in time, it is detected that there is a difference between the card detection latch signal by the comparator 3 and the card detection signal a, and a hardware interrupt and a software interrupt are generated through the same steps as at the time of insertion described above. Then, an interrupt routine corresponding to this software interrupt is executed, and a runaway of the system can be prevented.

Further, when the IC card is removed even though it is essential for executing the program, the CPU 7
display a message to that effect (for example, "Please insert your rlc IC card").

Effects of the Invention The present invention provides a CPU, a connector section having a plurality of electrodes connected to a power supply electrode and electrodes for transmitting address signals, data signals, and command signals provided on an IC card, and an IC card. a first means for generating a specific signal before the power supply electrode and electrodes for transmitting address signals, data signals, and command signals are separated from the electrodes of the connector portion when the electrode is removed from the connector portion; , C
By providing a software interrupt signal generation means for generating a software interrupt signal to the PU, and a second means for outputting a software interrupt signal to the CPU based on the output from the signal generation means, the IC When removing the card from the connector, a software interrupt signal is input before the code FFh is input to the CPU, and the CPU
This has the excellent effect of preventing runaway behavior.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an IC card reader according to an embodiment of the present invention, FIG. 2 is a plan view of the IC card, and FIG.
The figure is a flowchart showing the operation flow of the IC card reader of the same embodiment. DESCRIPTION OF SYMBOLS 1... Connector part, 2... Latch circuit, 3... Comparator, 4... Selector circuit, 5... Peripheral memory, 6 ...Fixed data output device, 7...Central control unit (CPU
), 8...Display device, 9...Pull-up resistor, 11...IC card body, 12...
...Active element, 13... Electrode, 13-1...
...Power supply electrode, 13-2...Ground electrode, 13-3...Card detection electrode, 13-4...
...Signal electrode

Claims (1)

[Claims] (1) I that exchanges data with an IC card that has an active element on a substrate and has multiple electrodes on the substrate.
The C card reader has a central processing unit (hereinafter referred to as CPU) that performs data processing, and multiple units connected to power supply electrodes and electrodes for transmitting address signals, data signals, and command signals provided on the IC card. a connector portion provided with electrodes; and a connector portion provided with an electrode of the connector portion, and when the IC card is removed from the connector portion, the power electrode and electrodes for transmitting address signals, data signals, and command signals are separated from the electrodes of the connector portion. a first means for generating a specific signal using the signal generating means; a second means for outputting a software interrupt signal to the CPU based on the output from the signal generating means; and connected to the second means via a second bus, and connected to the CPU via a third bus, and one of the first bus and the second bus. and a selector for selecting and connecting to the third bus, the selector being configured to connect the second bus to the third bus in response to a signal from the first means. IC card reader.