JPH11110497A - Device for monitoring ic card insertion and pulling-out - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an IC card insertion and pulling-out monitoring device for surely judging that an IC card is correctly mounted at a normal position. SOLUTION: When an IC card 102 is correctly inserted, a terminal contact 108 of the IC card 102 is connected with a connector 110 and power source current flows to the IC card 102. As the result, a voltage drop is generated in a resistor 105, and a comparator 107 detects the generation of a potential difference at each of input terminals and outputs the result to a microprocessor 109. The microprocessor 109 judges that the IC card 102 is correctly inserted based on the output from the comparator 107 and makes the IC card 2 start the reading or writing of the data.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC card insertion / removal monitoring device, and more particularly to an IC card insertion / removal monitoring device for monitoring an inserted or ejected state of an IC card.

2. Description of the Related Art As shown in FIG. 1, a conventional IC card insertion / removal monitoring device 1 has a terminal contact 6 connected to a connector 8 described later for reading or writing data.
, A power supply circuit 3 for supplying power to the IC card 2, a power supply switch 4 for controlling power supply to the IC card 2, and a check that the IC card is inserted into a proper position. It controls the IC card insertion / ejection detection switch 5 and the power supply switch 4 for detecting
A microprocessor 7 for starting data communication with the IC card 2 based on an output from the C card insertion / ejection detection switch 5, and the microprocessor 7 and the power supply switch 4 via the terminal contacts 6 of the IC card 2.
And a connector 8 to be connected to the The microprocessor 7 has the IC card 2 mounted in a regular position,
When the IC card insertion / ejection detection switch 5 detects the insertion, the microprocessor 7 determines that the terminal contact 6 is connected via the connector 8. Then, the power supply switch 4 is turned on to supply power to the IC card 2 from the power supply circuit 3 to activate the IC card 2 and start data communication with the IC card 2. Further, when the data communication with the IC card 2 ends, the microprocessor 7
The power supply switch 4 is turned off to deactivate the IC card 2 to make it removable.

However, in such a conventional IC card insertion / removal monitoring device, the proper mounting state of the IC card to the connector depends only on the IC card insertion / ejection detection switch. Therefore, the microprocessor tries to activate the IC card without knowing whether the IC card is upside down or reversed, and if the activation is successful, it is good. There was a problem that the reason for the failure could not be determined. Therefore, an object of the present invention is to provide an IC card insertion / removal monitoring device that can reliably determine that an IC card has been correctly mounted in a proper position.

SUMMARY OF THE INVENTION Accordingly, in order to achieve the above object, the present invention provides an IC card for reading or writing data, a power supply circuit for supplying power to the IC card, and an IC card. A power supply switch for controlling power supply from a power supply circuit to the card, a resistor that causes a voltage drop due to a flow of the power supply current when power is supplied to the IC card, and is connected to both ends of the resistor; A comparator for detecting that a potential difference due to a voltage drop of the resistor has occurred, and a microprocessor for controlling a power supply switch and determining whether to perform data communication based on a detection result of the comparator. I do. The present invention also provides an IC card from which data is read or written, a power supply circuit for supplying power to the IC card, a power supply switch for controlling power supply from the power supply circuit to the IC card, and an IC card. And a built-in resistor that causes a voltage drop when power is supplied to the power supply and an A / D converter that detects the occurrence of a potential difference due to the voltage drop between both ends of the resistor. A microprocessor that determines whether to perform data communication based on a detection result of the A / D converter.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an IC card insertion / removal monitoring apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram showing an embodiment of an IC card insertion / removal monitoring device according to the present invention. I of the present invention
As shown in FIG. 1, the C card insertion / removal monitoring device 101 has a terminal contact 106 connected to a connector 108 described later for reading or writing data.
C card 102, power supply circuit 103 for supplying power to IC card 102, and power supply switch 1 for controlling power supply from power supply circuit 103 to IC card 102
04, an IC card insertion / ejection detection switch 105 for detecting that the IC card has been inserted into a proper position,
When power is supplied to the card 102, a resistor 106 that causes a voltage drop due to the flow of the power supply current
Connected to both ends of the resistor 106,
And a microprocessor 10 that controls the power supply switch 104 and determines whether to perform data communication based on the detection result of the comparator 107.
9 and the IC via the terminal contact 108 of the IC card 102.
A connector 110 connects the card 102 to the microprocessor 109 and the power supply switch 104. The IC card insertion / removal monitoring device 101 having such a configuration operates as follows, for example. When the IC card 102 is inserted and the IC card insertion / ejection detection switch 105 detects the attachment of the IC card 102, the microprocessor 109 turns on the power supply switch 104 and supplies power to the IC card 102 from the power supply circuit 103. . If the IC card 102 is not inserted correctly, the terminal contacts 108 of the IC card 102
0, the power supply current does not flow through the IC card 102. Therefore, since the resistor 106 does not cause a voltage drop, the microprocessor 111 determines that the IC card 102 has not been correctly inserted, and does not read or write data to or from the IC card 102.
Here, when the IC card 102 is inserted into a correct position, the terminal contacts 108 of the IC card 102
0, and a power supply current flows through the IC card 102. As a result, the resistor 106 causes a voltage drop,
A potential difference occurs at both ends. Then, the comparator 107 detects that a potential difference has occurred between the respective input terminals, and outputs the result to the microprocessor 109. The microprocessor 109 determines that the IC card 102 is correctly inserted based on the output from the comparator 107, activates the IC card 102, and
To start reading or writing data. Further, the microprocessor 109 is provided with the IC card 1
When the reading or writing of data to 02 has been completed, the power supply switch 104 is turned off to deactivate the IC card 102 to put it in a state where it can be extracted. Therefore, according to the present invention, the microprocessor 109 detects whether power is supplied to the IC card 102, and the contacts of the IC card are correctly connected to the connector so that the IC card can be activated, that is, data can be read or written. It is possible to constantly monitor whether or not is possible. Next, another embodiment of the IC card insertion / removal monitoring device according to the present invention will be described with reference to the drawings. FIG. 2 is a schematic configuration diagram showing another embodiment of the IC card insertion / removal monitoring device according to the present invention. This IC card insertion / removal detection device 201 uses an A / D converter (not shown) built in a microprocessor 111 instead of the comparator 107 in the IC card insertion / removal detection device 101 shown in FIG. Even when the potential difference is detected, the same function as that of the card insertion / removal detection device 101 can be realized. That is, the potential difference generated between both ends of the resistor 106 is detected by the A / D converter,
As a result, the microprocessor 111
The IC card 102 is determined to be correctly inserted, the IC card 102 is activated, and data reading or writing to the IC card 102 is started. When reading or writing of data to the IC card 102 is completed, the microprocessor 111
04 is turned off to deactivate the IC card 102 to bring it into a removable state. Therefore, the microprocessor 111 detects whether or not power is being supplied to the IC card 102 according to the state of the A / D converter in the microprocessor 111, and the contacts of the IC card are correctly connected to the connector. I
It is possible to constantly monitor whether the C card can be activated, that is, whether data can be read or written.

As described above, according to the IC card insertion / removal monitoring device of the present invention, whether power is supplied to the IC card by the microprocessor based on the detection result of the comparator or the A / D converter. The IC card is correctly connected to the connector and the IC card can be activated. That is, it is possible to constantly monitor whether the data can be read or written. It can be reliably determined that the camera has been correctly mounted.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of an IC card insertion / removal monitoring device according to the present invention.

FIG. 2 is a schematic configuration diagram showing another embodiment of the IC card insertion / removal monitoring device according to the present invention.

FIG. 3 is a schematic configuration diagram showing a conventional IC card insertion / removal monitoring device.

[Explanation of symbols]

 Reference Signs List 101 IC card insertion / removal monitoring device 102 IC card 103 Power supply circuit 104 Power supply switch 105 IC card insertion / ejection detection switch 106 Resistor 107 Comparator 108 Terminal contact 109 Microprocessor 110 Connector 111 Microprocessor

Claims (2)

[Claims] An IC card for reading or writing data; a power supply circuit for supplying power to the IC card; a power supply switch for controlling power supply from the power supply circuit to the IC card; A resistor that causes a voltage drop when the power is supplied when the power is supplied, a comparator connected to both ends of the resistor to detect a potential difference caused by the voltage drop of the resistor, and a power supply A microprocessor for controlling a switch and determining whether to perform data communication based on a detection result of the comparator.
Card insertion and removal monitoring device. 2. An IC card from which data is read or written; a power supply circuit for supplying power to the IC card; a power supply switch for controlling power supply from the power supply circuit to the IC card; When a power is supplied, a resistor that causes a voltage drop when the power supply current flows and an A / D converter that detects that a potential difference has occurred due to a voltage drop between both ends of the resistor are built in. And a microprocessor for determining whether to perform data communication based on a detection result of the / D converter.